Did you think there was another reason for the US having silver planes during he war? Perhaps you hadn’t really thought about it. Welcome back! If you are new here make sure to hit subscribe to expand your knowledge on Military History and join the growing Premier History Community!
Could it be that the glare you see when the sun shines on it makes it so bright, its harder to see the silhouette. You know that something is up there, but you dont know what, or how high. i can also see now why the brits didnt like it haha
Weight savings is kind of obvious. But I was thinking about less obvious reasons. What I see in the pictures is a lot of planes of unpainted aluminum that are shiny silver in color. Then I also see planes of bare aluminum that are not so shiny. I was wondering if those surfaces were left unpolished to build up an oxide layer to make the planes less susceptible to sabotage from enemy commandos using mercury paste. Also I was wondering if those surfaces were purposefully anodized for the same purpose.
Some airplanes were in fact painted silver in some places. The P-51 wing, for example, was filled and painted back to about the 40% chord point, because they wanted to smooth it out in an attempt to maintain laminar flow.
A fun fact: the British De Havilland Mosquito was made of laminated wood, which was fine in the European and Mediterranean theatres of war. But in the Pacific the glue used in the Spruce/Balsa/Spruce sandwich would begin to delaminate in the heat and/or humidity. It because a serious issue in the Royal Australian Air Force because the Australian-built aircraft used a different glue that wasn't quite as robust. So the Aussies did some measurements and found that if you left a camouflaged Mosquito out in the Australian sun the temperature inside the wing would get above 125 degrees Fahrenheit. Stripping the camouflage paint wasn't an option - it's wood under there - so they did some tests and found that the best result was achieved by painting the aircraft silver. So the RAAF had a wooden aircraft that looked like it was made of metal, and for no other reason that Summer is bloody hot in Australia.
@@Mmjk_12 It wasn't available. De Havilland Australia had only built Tiger Moths until then. The Mosquito was an order of magnitude more complex. They had the blueprints from Britain, they had the Merlin engines, but everything else had to be sourced locally. The British glue was based on an organic glue that was (I believe, not sure) based on a substrate that was susceptible to attack from insects, which if you know anything about Australia would flash all number of red flags. So they needed a substitute glue but unfortunately that was more susceptible to heat. Swings and roundabouts. All up it delayed the introduction of the Mosquito into RAAF service by at least six months. Good thing they were ALSO license building the Beaufighter,which in its own way was a beast of a warplane .
Interesting -- the paint must have made a very reflective surface, as generally for heat reduction purposes in surfaces exposed to the Sun, white paint is more reflective than "silver" vehicle paint, unless the silver paint gives a mirror finish almost like chrome plating. Without it, the "silver" is darker overall than white, and thus absorbs more heat.
@@joemcgulligut7874 But white paint makes an airplane stand out more than silver paint, which might have been part of the calculus. In the early cold war US Air Force jets were mostly unpainted. In some locations the sophisticated F-105 spent a lot of time sitting out on the ramp under crappy weather. They started to have issues with surface corrosion as well as moisture seeping into the interior and messing with the electronics. The solution was to actually paint the airplanes to seal the surfaces. Since camouflage was not in use at the time, they painted them with a silver paint that looked a lot like unpolished natural metal. If they painted them white, they would not have looked like combat aircraft.
@@joemcgulligut7874 It would depend on what paint they had in bulk that can stand up to the rigors of a combat zone. So white may give a better result, but is of no use if the only white paint that is available fades or peels or otherwise deteriorates too quickly. But silver-dope? Well, that's been used for aircraft since the Wright Brothers.
Strangely bombers that were painted were faster and more efficient than unpainted bombers. The effect of paint wicking into and smoothing out the panel work made them more aerodynamic. Later unpainted bombers matched this by using flush rivets. Although the initial paint weight was a handicap the painted aircraft used less fuel but gave more range. Strange but true.
Now, I have not done any math to test this out. But the larger the plane, the less proportionally the paint should be. Since the coat of paint is about as thick on a larger plane as a small one. So that could be a small factor too. I am sure one could also compare the proportional surface area vs internal volume to of these planes.
Additional tests of unpainted aircraft confirmed increased performance results. The decision to stop factory painting unless otherwise advised on an individual basis was initiated in October 1943. By January 1944 all planes coming off the production line were not painted. Instead, they received a wax coating or were over-sprayed with a lightweight clear coat. Not only were these unpainted aircraft faster; they were also lighter. This meant increased range for fighters and bombers and extra bomb capacity for the latter. No record exists about how much a gallon of paint used on the aircraft weighed. Contemporary reports stated that with the elimination of the paint, fighters would be “fifteen to twenty pounds lighter” and heavy bombers would “lose seventy to eighty pounds.” One recent study on the subject noted that the paint during this period was undoubtedly lead-based and “probably copper fortified.” A gallon of such paint could weigh as much as 30 pounds, though for aircraft it was more likely to be in the 10-pound range. A B-17 has a surface area of 4,200 square feet and took about 35 gallons of paint to coat. If the paint weighed 10 pounds a gallon wet, after accounting for evaporation the weight would be roughly 300 pounds. Given that figure, eliminating the paint would indeed be a major weight reduction.
I had an Engineering manager who had been a B-24 crew member. He remarked that the interior was not only unpainted but many parts still had inked mill markings that suggested they hadn't even been cleaned before assembly. These planes were not built for long service life so corrosion protection probably not considered cost effective.
My understanding is that the silver color comes from polished aluminum, which was the primary material for the skin, I think. Not too much corrosion hazard, in that case? Maybe the rivets?
Mill and watermarks on aluminium sheet were deliberately retained. If you read the North American process manual for the P-51 it specifically says don’t remove them.
The ‘silver’ P-51’s in this video do actually have painted silver wings (fuselage was un-painted apart from anti-glare panel). They received bondo filler and primer applications to assist the laminar flow performance of the wing and finished with silver paint.
What I find interesting is that silver B-17s, despite the weight reduction, were slower and less fuel efficient than painted B-17s because the paint filled cracks and to some extent flushed out rivets. Edit: I think overall the absence of paint actually was beneficial to most aircraft. The B-17 was just built that way.
Don’t underestimate the effect of finish. I read the memoirs of a German nightfighter, who wrote it seemed unnecessary for him to change away from the BF110 to a more potent plane like the HE219, as he had his plane waxed, panel lines fillered and glossy finish, which made his plane, even with the antler-like antennae, 40 km/h faster. The same thing I heard from my WW I fighter ace grandpa, who said after 3 victories or so your chances of survival rose, as you got better planes and more important, aircraft mechanics.
@@carlwear1249 No, this video is wrong, painting an aircraft as large as a B17 only added 75 lbs to it, not the "hundreds of pounds" claimed in this video and by so many other sources, the mere addition of 75 lbs was more than offset in the reduction of drag from the paint smoothing over the lap joints and rivets on the exterior of the aircraft, a painted B17 picked up 4 knots of speed and about 200 miles of range from the reduction in drag. In 1944 the US military had the aircraft manufacturer's stop painting aircraft at the factories because it was too time consuming and caused choke points in production and delays in the delivery of aircraft, after that whether or not they were painted was left up to the individual theater commander's. Corrosion resistance also has nothing to do with it, well before WW2 a special aluminum sheet called Alclad which does not corrode was developed for aircraft and other things that need to be made of aluminum and have corrosion proof properties. Pure aluminum does not corrode but it's about as strong as clay, when alloys like copper and tin are added to it to give it strength it also makes it susceptible to corrosion, Alclad is an aluminum alloy sheet that has a pure aluminum coating on it, it's strong like regular alloy aluminum but is also corrosion proof, painting military aircraft never had anything to do with keeping them from corroding, it was strictly for camouflaging.
You note it was not silver paint, but this wasn't always the case. To help achieve the P-51's laminar flow wing characteristics, the wings were filled and sanded completely smooth, and then given a coat of silver lacquer.
This is true, you beat me to it. It is the reason why the fuselage of P-51 could be a patchwork of different shades of "silver" depending on the state of the bare aluminum panels, whereas the wings were usually a uniform silver color.
The wings of otherwise unpainted F-104s were also painted to maintain smooth airflow. The upper surface was painted gloss white and the lower surface a standard USAF gray color.
I recall my Grandfather talking about something similair. I was very young but remember him talking about his P-51 air crew buffing his plane with some kind of wax. He spoke about getting more fuel efficiency.
There were some extremely wild paint schemes used on USAAF bombers besides the normal olive drab. These were the assembly ships or "judas goats" used to assist B-17s and B-24s in getting organized into combat box formations quickly with minimal use of fuel and in radio silence. To give the bombers visual clues and instructions, the judas goats were painted in bright stripes or polka dots like giant flying clown cars. They were also equipped with several flare launchers and a generous supply of flares in various colors used to signal the bombers as they formed their combat boxes. Other than flares, the assembly ships were completely unarmed.
Notably, the P-51s did have a stripe of dark pain from the front of the cockpit forward to the propeller. This was to reduce potential reflective glare shining into the eyes of the pilots.
Veteran German flack gunner to a new recruit: "If it's brown planes, it's the British. If it's silver planes, it's the Americans. If it's no planes whatsoever, it's us."
My Grandfather was a B 24 crewmember in the SW pacific the 24's he trained on in the states were green,but when they where given brand new 24's to fly to their area of operations overseas they where bare metal. This is totally due to weight savings.
WWII US Bombers did a video that mentioned the amount of distance an unpainted B-17 got over one that was painted. Hundreds of miles and that made a big difference in the Pacific theatre.
Weight-savings was indeed a factor. But when you need to churn out a lot of equipment, time-savings is also a major incentive. Both were clearly important enough to outweigh the maintenance concerns of bare metal. And if you think about it, the US Navy never implemented this. I never saw any US Navy aircraft that was bare metal during WW2.
We had a customer at work that I became friends with. He was a ball turret gunner on a B-17 in WWII. His plane was an early G model with the improved forward guns, but was also bare metal. It was mid in 1943 when bomber raids didn’t go deep into Europe. Their mission was to the Netherlands in a single box of 12 to 16 bombers and they were the only bare metal aircraft. The Germans picked them out as their primary target and they were shot down. He survived and was a POW for about 2 years and after release they had to lay on the ground spelling out POW because of straffing Allied fighters at least once.
b 17 bombers were the old exposed Rivet design and it was found that teh Paint on a B17 helped the air flow. the later unpainted Aircraft lost cruse speed at the same Throttle settings. later Aircraft like the B29 and fighters with flush mounted rivets were faster without paint.
@@badlt5897 5’ 4” at most. But a very well respected orchid breeder. Their B-17 came from the Wichita plant as he remembered the tail number and found it through a printed resource. He thought it was a very late F model, but the record had it as an early G. Could be the ship’s plate had an error with F already fixed on it.
The more of these built, the better since the targets could be spread among more planes. The process to produce them was helpful along weight, but also along production. The mistake made in the case of these types of planes, they didn't send along paint and gear to finish the job by the crew on the ground maintaining it.
Wasn't 'silver' it's bare aluminum. And Aluminum doesn't rust, it corrodes. I knew about the weight factor of paint. On the first B 29 prototype it was painted but they gave up on that for all the reasons you said. The US Navy kept their planes painted the three color blue pattern till about 1944 then they just painted them all a dark gloss blue. When you see a squadron or bomb wing in Europe around that time with some painted and some not it looks like a WWII version of Richthofen's Flying circus. Good relevant footage, Well done.
@@toqtoq3361rust is a specific corrosion product. Specifically it is hydrated iron III oxide. No metals other than iron and steel can produce rust. Only the ignorant claim other metals rust, they corrode.
@@neiloflongbeck5705in common parlance 'rust' and 'corrosion' are considered interchangeable terms. Beeeecause rust IS a form of corrosion. Stop being a dick.
This video answered questions I have had since I was a kid. I am 70 now. I had a P-51 Mustang model with a gas engine that was silver. I never know why until. Thank you very much!
@Brownbear77777 I’d bet my next pension checks that you never had a silver P-51 Mustang. I bet it was made of aluminum. Silver is way too expensive and heavy.
@@robertwilliamson922 He is talking about a "model" plane, not a full-scale plane, you donut. Did they not teach you comprehensive reading in school? Silver as in color, not material, you goof. Are you that dense?
@@robertwilliamson922 I would bet that he was referring to a "metallised" (chrome/silver colo(u)r) mainly plastic control-line model, and by "gas" he meant a methanol based fuel BUT anyone who played with piston powered model planes back in the day would know what he meant.
@@robertwilliamson922 Back when motorcycle technology and aluminum metallurgy were less developed (30s or 40s ?), a British motorcycle racing group went so far as to inquire around the jewelry district as to the cost of casting heads out of silver, because of its thermal conductivity, to help with overheating problems. They found that in addition to the expense, the alloy level needed to get acceptable strength largely negated the desired conductivity.
The WET paint, in the can, was 8 lbs. per gallon, but after application, when the solvents evaporated, the dried paint wasn't that heavy. It probably was to save time in manufacturing, and the expense of the paint itself. Still, certain internal parts were painted Zinc Chromate green, and still are to this day. Especially Navy aircraft that are exposed to the salty environment. Thanks for the video. Jon
Interesting point! The internet tells me that dry paint is 60% the weight of wet paint so 8lbs would be 4.8lbs. lol, you made me learn something today, thank you.
Paint pigments are more dense than water. Water weighs 8.3 pounds per gallon. Water has a density of 1 so even though it is denser than the organic liquids used to comprise the paint, the pigments would still be heaviest part of the paint. Certain pigment colors used a lot of heavy metals which made them much more dense; easily 4 or 5 times as much. I think the 8 pounds per gallon applied weight is probably conservative.
No record exists about how much a gallon of paint used on the aircraft weighed. Contemporary reports stated that with the elimination of the paint, fighters would be “fifteen to twenty pounds lighter” and heavy bombers would “lose seventy to eighty pounds.” One recent study on the subject noted that the paint during this period was undoubtedly lead-based and “probably copper fortified.” A gallon of such paint could weigh as much as 30 pounds, though for aircraft it was more likely to be in the 10-pound range. A B-17 has a surface area of 4,200 square feet and took about 35 gallons of paint to coat. If the paint weighed 10 pounds a gallon wet, after accounting for evaporation the weight would be roughly 300 pounds. Given that figure, eliminating the paint would indeed be a major weight reduction.
Of more limited use was the fact that Recon planes were found to benefit from being lightly painted and then polished to remove any bumps on the skin of the plane. This improved fuel efficiency, and made them faster. The video stats correctly that the lack of paint really did save weight time and money. Money savings may have been the biggest factor in this.
Weight was really the big one. If the plane did not need the paint for protection from seawater it was a huge removal of well over 100 pounds of paint. Skipping the full paint also shaved about 2 days off each planes production. And while skipping the paint reduced costs. It's not really in the ways you would think. It was more it reduced the massive logistics chains needed to get the paint to the plane factories. And it eliminated a point of production bottleneck. The paint was still being made and used. Ground vehicles needed painting. But by cutting the planes out of the paint loop created efficiencies throughout war production.
There’s another RUclips video that shows the US Army’s very detailed studies on cost benefit of painted vs non. Pretty good video ruclips.net/video/420fO_-u0nE/видео.htmlsi=u3lOR9Eh1JHYxdp7
Never heard of that. 5 Grand, the 5000th B-17 Built was bare metal, but, factory workers where allowed to paint their names all over the plane and it was pretty well covered in signatures. It proved to be slower than the other bare metal bombers. So how does paint help? It would if the plane had been smoothed and the paint highly polished, like race planes, but, these where mass produced aircraft that used flat paints for camo.
@@mypl510 Australia had a wing (three squadrons) of Supermarine Spitfires fighting the Japanese over the Northern Territory and New Guinea. The Wing Commander (Clive Caldwell) was always on the lookout for any edge he could get, so as a test he ordered his own aircraft to be stripped of paint and the bare metal waxed and polished. The end result was that his aircraft was up to 20-25mph faster than any of the other Spitfires - which was A Good Thing - but it also meant that his Spitfire stood out like dogs-balls when he was leading his wing against Japanese Zeros, which from his PoV was not good. Not good at all. So it was a short-lived experiment. But it showed that if you (a) stripped the paint off and (b) then waxed and polished the bare metal then (c) you got a significant increase in speed.
@@mypl510 See World War II Bombers or Greg's Autos and Airplanes for information on speed and fuel burn. The difference wasn't much but it was there. And when 5 Grand got to a squadron the names probably came off. Just like I doubt Yipee the red P-38 stayed red.
I remember reading a story told by an American ace, I think it was Bud Anderson, who made a comment to his crew chief that he liked the unpainted, polished aluminum look. The next morning, Anderson said that went out to his Mustang and found that instead of the green camouflage scheme he was used to, it was now gleaming, polished silver, and standing next to the aircraft was an exhausted crew chief and ground crew whose hands looked like raw meat from a long night spent using steel wool to strip off the old paint.
That has to have been the same story I've read! Only differences I remember was that he made the comment to his crew chief after it had snowed. Some pilots thought the bare aluminum offered better camouflage over the snow than the olive drab. He mentioned it might be time to go to the winter scheme. Then, the reason their hands were so red was because they used the only paint stripper they had readily available and that was aviation gasoline! Always loved that story
I remember Pappy Boyington writing in his memoirs that he recommended the Marine Corps adopt the bare aluminum scheme. I think his argument is that it would make the aircraft more visible to the enemy and thus facilitate dog fights (!)
Camouflage is important to avoid being jumped from above, when You're in a disadvantage. That's a main reason why the aircraft - camouflage was invented during WWI. During WWII British fighters' camo was changed into grey - green because it was better on higher altitudes than brown - green, when You're flying at 5000m and Your enemy is approaching at 7000m. In the end of WWII the German camo was changed from grey shades into dark grey (or brownish) and green, because they could be jumped at low altitude. Some WW2 US units introduced improvised camo on their shining fighters from the same reason.
I’m posting this before finishing the video, but already know the deal. At the beginning of the war they were concerned about aircraft being spotted, hence, the camo paint jobs. But later on in the war, it didn’t matter as the contrails from thousands of bombers and fighter escorts gave away their positions anyway. It also saved weight, time, and money to send them out in bare aluminum. On something like a Lear 25 like I used to work on, the paint added around 500 lbs or more to the aircraft’s overall weight. On a bomber or fighter, that’s another bomb it can carry, or another 500-1000 lbs of fuel.
I work with a WW2 army veteran. He told me a few weeks before the war ended. The sky was full of bomber planes. He explained it look like a few miles long sheet of Reynolds wrap in the sky Reflecting from the sun rays.
I had assumed that the silver finish was down to weight saving, but it is interesting to hear the other reasons of: not necessarily being required and time saving in the factory, I can imagine that during war time the latter was particularly important.
A painted B-17 was actually faster than an unpainted one. The Army Airforce tested them against each other and it was decided that the paint smoothed out all of the rivet heads and thus made it slicker through the air. The weight claim did not make any difference.
That might go for riveted aircraft, especially big ones like the B-17, but I'm fairly sure fighters like the P-51 were welded because that's more aerodynamic. So there paint would make quite a bit of difference.
The weight savings - 200-300 pounds on a B-17 or B-24 - meant that they could carry more fuel or other load for a bit longer range! Avgas weighs about 6-pounds/gallon, so that 300 pounds saved in paint weight meant that they could theoretically carry another 50 gallons of fuel. That 50 gallons is another half-hour of fuel - enough to fly another 70-90 miles.
The P-51D had the wing panel joints, rivets filled, sanded smooth, primed and painted silver to give the smoothest surface. Canvas covered elevators were also painted. Underside of the wings had one coat of filler. Just google "P-51 wings painted" and you'll see.
It seems the silver planes were also sending a message. Recently I saw a story recounting German Luftwaffe men examining a shot down P-47. They noted it's gleaming finish and the fact that the plane showed almost no wear indicating that it had recently arrived at the front fresh from the factory. They compared that new fighter to the worn and repeatedly repaired planes they flew and they understood what it meant.
The German soldiers had a joke about aircraft recognition in the last year of the war: "If they are green, they're British. If they're silver, they're American. If they're invisible, they're German." Imagine demoralization so bad you use black humor to describe it.
P51s were used as bomber escorts throughout the European Theatre. Silver made it easy for bomber gunners to recognize friendly aircraft, and minimize accidental shootings.
One last bonus is that the paint not used to paint the planes could be used elsewhere, or less paint needing to be purchased/funds going somewhere a little more important than paint.
They stopped painting aircraft camouflage when they gained air superiority. Cost savings and weight were also a factor. Early P-47s entered the war painted olive drab but by the end, were left bare aluminum. Even early B-29s were painted. Mustangs re-designated A-36 Apaches were painted
That's pretty much what I was told growing up. For the last year or so of the war: 1. Allies had Air superiority, 2. Streamline production, 3. Save the taxpayers some money.
A painted B-17 was actually more aerodynamic than the unpainted version and used less fuel. A B-29 was bare aluminum since it used flush rivets and the skin was put together in a butt joint, not an overlap. I want to say the same goes for the B-24 but I would have to do more research on that first.
Silver planes weren't only unpainted aluminum. On the silver P-51s, for example, though the silver fuselages were bare aluminum, the laminar wings were not. The were puttied to remove seams and rivet dimples, and then painted silver.
The brits did not like silver because they needed every plane to last as long as possible. Also their experience of the war taught them not to make a bigger target for the enemy. The US had massive resources and did not really care about losing planes as they had the men and the money to replaced them, the British were the opposite. It shocked the brits how the US had a complete disregard for their service men in the air war over Europe.
This is true. The paint filled all of the little nooks and crannies in the uneven surfaces of the aircraft. The paint also "raised up" the surface of the aircraft so the rivets didn't protrude as much.
@1:47 Nice picture of the B-24 Willow Run Plant in Ypsilanti, Michigan. Otherwise, even though the late-war US aircraft were silver, they still had to paint the forward cowls to eliminate the glare which would blind the pilot.
The camoflauge of the aircraft wasn't just for the time they were parked on the ground, but so they'd be more difficult to detect from above while flying (probably far more important). Clearly Navy aircraft weren't painted with blue on top to make them harder to spot on a carrier deck (or even while on land based airfields) but against the blue of the ocean while in flight.
The Navy in the Pacific operated at much lower altitude than the planes in Europe. Most combat took place around 12000 to15000 ft. Europe was 20-30. Hence the blue paint.
@@karlhumes6110 Combat has literally nothing to do with it. Once you're in combat, no amount of cam is going to hide you as you're way too close. The point is you want to hide from interceptors at high altitude while you're closer to the ground/ocean than they are and on your way to a surface target. Fighters require less cam for this reason but still don't want to be spotted from above if possible. A silver Mustang would've stood out on a sunny day like a search light while it was down on the deck strafing ground targets, but they weren't worried about it by that stage of the war.
I had heard that towards the end of the war as the allies had attained air superiority the powers that be decided it was no longer necessary to try and hide behind their camouflage but wanted the enemy to come up and fight with them. If they could be defeated in the air that would help hasten the end of the war.
There is a bitter truth to this. A significant aspect of the SBI was that it drew German resources away from other areas. The Allies we’re picking a fight for the fight’s sake, damage on the ground aside.
I'm a private pilot, and once I was sharing the pattern around an airport with a natural metal DC-3. At certain angles, the skin reflected the green of the ground vegetation, making it difficult to keep track of its position.
@@petesheppard1709 I saw a pilot doing his yearly polishing of his bare high wing. He told me that it was difficult for those on the ground to see it on approach, as it reflected the sky from around and behind its slender frontal profile.
That is true, but there were some other reasons: 1) combat took place at a lower altitude (consider torpedo bombers, which operated "on the deck") so blending in with the blue of the sea was still advantageous and 2) when returning to the carrier you would often have to really throttle back to conserve fuel, which left you vulnerable to being "bounced" so, again, blending into the sea was a good idea.
a true fact, the paint actually decreased drag especially on the B17, but the war was almost over and never went back to painting them. the paint would fill in seams and rivets which decreased the drag while not painting them increased this drag and increased fuel consumption.
Es fehlte der Lack um sie an zu streichen? Mein Vater hatte einen Karabiner in der Wehrmacht der wahr nicht brüniert und das Holz nicht abgedunkelt. Es fehlte an den Mitteln das zu tun im Herbst `45.
The Allied strategic bombing campaign contributed greatly to the Axis shortages of bluing, paints, and other petroleum products, as well as aluminum, molybdenum and other chemical additives.
My favorite paint scheme is the one they put on a B-25 Mitchell bomber as General Dreedle's plane in the Catch 22 movie. it was a sort of beach sand color with general's flags (like you would see on the front of a limousine) and white wall tires.
Especially with the heavies, not painting them saved weight and every pound saves means an increase in range. Often the Mustang and Thunderbolt pilots used to paste wax their aircraft to make them more "slippery" and got a few extra knots out of them.
I’m a former aircraft mechanic and worked on Lear 25’s. Besides doing that, I would polish the nacelles and intakes of the engines to a mirror finish and the pilots picked up about 10-20 knots and increased range due to less fuel consumption.
I would have guessed that silver would reflect the ambient colour of the atmosphere around, changing from dawn til dusk, making it harder to spot. Thanks for the video
The sheet aluminum on the outside panels are pure aluminum bonded to the main thickness which is not pure but alloy aluminum. The base metal of alloyed aluminum was subject to corrosion while the thin layer of pure aluminum protected the base metal because it did not corrode.
Just one more step in explanation. The pure aluminum ‘akshually’ oxidizes very readily, but the resulting oxide is a very hard, tight layer that seals the bulk against further corrosion. When I said very hard, it is; it’s the same stuff on aluminum oxide sandpaper, and ruby. When they were coating the near perfectly misground Hubble main mirror, they sputtered the aluminum on in a vacuum chamber. They then had to immediately, in a very few minutes, coat it with a protective coating, of a fluoride base I think, to prevent the residual oxygen from reacting with the reflective surface and producing infrared absorbing oxide to negate one of the prime design goals of the telescope.
The Enola Gay was actually PAINTED silver. This was so that it would reflect more radiation....it was NOT left bare metal!! Her fighter we're also painted silver....
There is a bit more to it as p-51s/47s had a high quality of manufacture where other types had less. The silver b-17s were slower than there painted counterparts because the overall drag from panel gaps which would be otherwise filled with paint. ruclips.net/video/420fO_-u0nE/видео.html
The weight save was critical because it allowed Allied planes to fly deep into Germany from British bases. I think that may have inspired American Airlines to have a natural metal finish on their airliners until last livery change.
With modern airliners having more and more composite construction, if you'd leave them unpainted you won't get a natural metal finish anyway. Airliners are often painted white, because it is highly visible (the opposite of camouflage!) and being reflective it helps keep the cabin cool.
@@jbepsilonand not just the cabin but the structure too. This is why carbon and glass fibre airlines and gliders are predominantly white, even in the cloudy UK.
There was actually a sizeable difference in performance. A polished metal airframe could add 15-20 mph to the airspeed. British used the S Type aircraft colours that replaced the previous Matt types. The S stood for Smooth and they were high gloss producing a low drag finish increasing the aircraft top speed. At the same time 'whip' antenna replaced mast and wire and as were flush riveted.
there is another channel that said that the unpainted B17's were slower than the painted ones and used more fuel to keep up, the painted ones had minor flaws in the planes panels filled in with paint and that added to the performance
Why are you consistently referring to silver coloured aircraft, it’s polished aluminium (GB) or aluminum (US). If you produce content, at least do your research properly. A lot of modern aircraft still have polished pure aluminium clad alloys heated areas. BTW the P51 wings were treated with filler and painted in high gloss „silver” grey. And British aircraft were sometimes painted with a aluminium pigmented paint.
All I know for sure is that after I polish my aluminum Grumman canoe, it's faster and has a longer glide - the time between the last stroke of the paddle at full speed, til the boat stops. Friction is the enemy of efficient movement through any mass, no matter the speed. Even if it's just 3mph.
By 1945, the US was running short on Olive Drab paint (along with a lot of other things) and by then, the numbers of American aircraft in the air vs. axis aircraft (German and Imperial Japanese) nullified any significant reason to camouflage them.
Good video! My grandfather flew P-51Ds against the Japanese toward the end of the war. His aircraft looked like some of the ones in your video: base silver with black on the engine cowling, red by the prop and on the aeleron. And a single red stripe at an angle down the sides. Tbh, I've always just thought it was due to his unit's SOP. Never realized it was weight and money savings- makes sense though. He never got shot down, so I guess it worked successfully for him. Lol!
In a definitive official history of the spitfire development, (The Spitfire Story by Alfred Price and Jeffrey Quill), tests were shown to have been undertaken as to which superficial modifications were worth undertaking to improve performance factors. I think on a mk.v model. These included rear view mirror removal, application and position of flush riveting, curved front windscreen, and the gloss polishing of the standard matt paintwork, plus careful attention to filling panel gaps. All of these added about 18mph to the top speed if I remember correctly, with the gloss finish contributing the most to this improvement. Some of these detailing were subsequently included into production procedures.
Those tests were done well before the Mk V, on the pre-PRU photo-recce Spitfires back in '39 - these had their panel lines chalked flush , and paint polished for speed
I've seen videos and interviews of WWII pilots and maintenance crew and the main reason was they would use camo colors during mid spring though early fall and then remove the paint during Late fall to early spring. Because Europe is such a snowy place during winter, silver tended to blend in with the snow and make it harder for enemy aircraft to see them from above during flight. camo colors had the same effect during mid spring to early fall when there wasn't snow on the ground.
No you didn't, and that had absolutely nothing to do whether they were painted or not. The reality is and what the creator of this video obviously didn't know is that in late 43 they quit painting aircraft at the factories because it was too time consuming and caused choke points in production and delayed delivery of the planes, theater commander's were screaming for aircraft and they told the high command they didn't care whether or not they were painted as long as they had wings and could fly was all they cared about, so from that point on whether or not they got painted was entirely up to the theater commander's and was to be done by the units that got them if they wanted them to be painted, they never had any problems seeing them from the contrails they left behind and you can't hide hundreds of 4 engine bombers or their escorts, the Germans had radar and knew exactly where they were at, the camo paint on the top was because originally they thought that US air bases in England might get bombed which is something that as it turned out never happened anyway, the flat gray on the bottom was because they thought originally that it'd make it difficult to see by AA crews but as that turned out German AA guns had radar along with the fact that with hundreds of contrails in the sky everyone from Sweden to Switzerland could see a formation of 300 B17's and their escorts, many units never bothered to paint them after receiving them when the started showing up unpainted and some simply did it become some military commander's being the way they are wanted every aircraft in their unit looking the same. Ground crews had plenty to do in between missions like repairs and replacing engine's along with preping aircraft for the next mission, as it was they worked around the clock keeping them flying and had no time to strip the paint off of hundreds of aircraft. Quit making things up.
I've been a fan of warbirds for years, made a few models of them when I was younger, and often wondered about the silver ones, even thinking to myself: "this would be lousy for camouflage", but today I wonder no more! Thank you so much for answering a question that I had wondering about for years! The fact that not applying paint would make the aircraft lighter and therefore faster seems so simple, yet I never even thought about it before!
Thank you for getting straight to the point! That was very informative without the clickbait other videos give these days. Yes, paint is quite heavy, which is why Eastern Airlines didn't paint their commercial airliners.
The maintenance on a bare aluminum airframe is actually much easier. It’s easier to spot problems than when they are covered with paint. They are also much easier to keep clean. A clean aircraft will allow a higher speed as well.
I remember reading many years ago . About a P-51 pilot that mentioned his ground crew kept his bare aluminium plane well waxed. Said it added a bit of speed . I would imagine reducing corrosion resistance too.
The waxing smoothed the surface, and therefore improved the airflow over the wing. And the P-51 had a laminar-flow airfoil design, so keeping the airflow smooth was a very good thing. The British tried very hard to get semi-gloss paint that was hard-wearing, because the alternative (matte paint) added much too much drag.
@@SevenSixTwo2012 Most of the exposed panels of the P-51 was aluminum, so corrosion from any wax isn't really going to be an issue. The much bigger problem was corrosion caused by electrolysis whenever aluminum sheets are riveted onto steel frames.
Perhaps the AI speech synthesizer didn’t know if the “gee” was pronounced with a hard g like “get ” or a soft g like “gin” and so decided to play it safe and leave the syllable out altogether.
It’s really heavy wet in the can, but much lighter once the solvent vehicle dries away. Eight pounds a gallon is just what petroleum spirit weighs. The pigment must weigh almost nothing.
First thought was that it had to do with blending in - sky or ocean (blue)...but cool to learn how much sense it made to not add the additional weight. Subscribed - good channel!
Did you think there was another reason for the US having silver planes during he war? Perhaps you hadn’t really thought about it.
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Could it be that the glare you see when the sun shines on it makes it so bright, its harder to see the silhouette. You know that something is up there, but you dont know what, or how high.
i can also see now why the brits didnt like it haha
Weight savings is kind of obvious. But I was thinking about less obvious reasons.
What I see in the pictures is a lot of planes of unpainted aluminum that are shiny silver in color. Then I also see planes of bare aluminum that are not so shiny.
I was wondering if those surfaces were left unpolished to build up an oxide layer to make the planes less susceptible to sabotage from enemy commandos using mercury paste.
Also I was wondering if those surfaces were purposefully anodized for the same purpose.
I once read that painting a B747 added five tons to the aircraft's overall weight.
Some airplanes were in fact painted silver in some places. The P-51 wing, for example, was filled and painted back to about the 40% chord point, because they wanted to smooth it out in an attempt to maintain laminar flow.
@@Keith-n7lnot quite that much, but it definitely adds a LOT of weight to the aircraft
A fun fact: the British De Havilland Mosquito was made of laminated wood, which was fine in the European and Mediterranean theatres of war. But in the Pacific the glue used in the Spruce/Balsa/Spruce sandwich would begin to delaminate in the heat and/or humidity. It because a serious issue in the Royal Australian Air Force because the Australian-built aircraft used a different glue that wasn't quite as robust.
So the Aussies did some measurements and found that if you left a camouflaged Mosquito out in the Australian sun the temperature inside the wing would get above 125 degrees Fahrenheit.
Stripping the camouflage paint wasn't an option - it's wood under there - so they did some tests and found that the best result was achieved by painting the aircraft silver.
So the RAAF had a wooden aircraft that looked like it was made of metal, and for no other reason that Summer is bloody hot in Australia.
@@Mmjk_12 It wasn't available. De Havilland Australia had only built Tiger Moths until then. The Mosquito was an order of magnitude more complex.
They had the blueprints from Britain, they had the Merlin engines, but everything else had to be sourced locally.
The British glue was based on an organic glue that was (I believe, not sure) based on a substrate that was susceptible to attack from insects, which if you know anything about Australia would flash all number of red flags.
So they needed a substitute glue but unfortunately that was more susceptible to heat.
Swings and roundabouts.
All up it delayed the introduction of the Mosquito into RAAF service by at least six months.
Good thing they were ALSO license building the Beaufighter,which in its own way was a beast of a warplane
.
Interesting -- the paint must have made a very reflective surface, as generally for heat reduction purposes in surfaces exposed to the Sun, white paint is more reflective than "silver" vehicle paint, unless the silver paint gives a mirror finish almost like chrome plating. Without it, the "silver" is darker overall than white, and thus absorbs more heat.
@@joemcgulligut7874 But white paint makes an airplane stand out more than silver paint, which might have been part of the calculus.
In the early cold war US Air Force jets were mostly unpainted. In some locations the sophisticated F-105 spent a lot of time sitting out on the ramp under crappy weather. They started to have issues with surface corrosion as well as moisture seeping into the interior and messing with the electronics. The solution was to actually paint the airplanes to seal the surfaces. Since camouflage was not in use at the time, they painted them with a silver paint that looked a lot like unpolished natural metal. If they painted them white, they would not have looked like combat aircraft.
@@joemcgulligut7874 It would depend on what paint they had in bulk that can stand up to the rigors of a combat zone.
So white may give a better result, but is of no use if the only white paint that is available fades or peels or otherwise deteriorates too quickly.
But silver-dope? Well, that's been used for aircraft since the Wright Brothers.
@@johnreynolds7996 the beaufighter is a solid plane and a worthy foe in todays sponsor war thunder
Strangely bombers that were painted were faster and more efficient than unpainted bombers. The effect of paint wicking into and smoothing out the panel work made them more aerodynamic. Later unpainted bombers matched this by using flush rivets. Although the initial paint weight was a handicap the painted aircraft used less fuel but gave more range. Strange but true.
Spot on! B17 vs B29 was a great example. B29 riveting process meant it was faster without paint. B17 was the opposite.
Da red wunz go fasta!
Now, I have not done any math to test this out. But the larger the plane, the less proportionally the paint should be. Since the coat of paint is about as thick on a larger plane as a small one. So that could be a small factor too. I am sure one could also compare the proportional surface area vs internal volume to of these planes.
Additional tests of unpainted aircraft confirmed increased performance results. The decision to stop factory painting unless otherwise advised on an individual basis was initiated in October 1943. By January 1944 all planes coming off the production line were not painted. Instead, they received a wax coating or were over-sprayed with a lightweight clear coat. Not only were these unpainted aircraft faster; they were also lighter. This meant increased range for fighters and bombers and extra bomb capacity for the latter.
No record exists about how much a gallon of paint used on the aircraft weighed. Contemporary reports stated that with the elimination of the paint, fighters would be “fifteen to twenty pounds lighter” and heavy bombers would “lose seventy to eighty pounds.” One recent study on the subject noted that the paint during this period was undoubtedly lead-based and “probably copper fortified.” A gallon of such paint could weigh as much as 30 pounds, though for aircraft it was more likely to be in the 10-pound range. A B-17 has a surface area of 4,200 square feet and took about 35 gallons of paint to coat. If the paint weighed 10 pounds a gallon wet, after accounting for evaporation the weight would be roughly 300 pounds. Given that figure, eliminating the paint would indeed be a major weight reduction.
Paint made the old style rivets a bit more streamlined. Better rivets were later designed to cut drag.
I had an Engineering manager who had been a B-24 crew member. He remarked that the interior was not only unpainted but many parts still had inked mill markings that suggested they hadn't even been cleaned before assembly. These planes were not built for long service life so corrosion protection probably not considered cost effective.
My understanding is that the silver color comes from polished aluminum, which was the primary material for the skin, I think. Not too much corrosion hazard, in that case? Maybe the rivets?
@@mmm-mmm and MB not even having the best stats, it just have pretty good marketing/propaganda value and was popularized.
I've heard that, at peak production, they were turning out B24s about one an hour.
Mill and watermarks on aluminium sheet were deliberately retained. If you read the North American process manual for the P-51 it specifically says don’t remove them.
The ‘silver’ P-51’s in this video do actually have painted silver wings (fuselage was un-painted apart from anti-glare panel). They received bondo filler and primer applications to assist the laminar flow performance of the wing and finished with silver paint.
What I find interesting is that silver B-17s, despite the weight reduction, were slower and less fuel efficient than painted B-17s because the paint filled cracks and to some extent flushed out rivets.
Edit: I think overall the absence of paint actually was beneficial to most aircraft. The B-17 was just built that way.
I had heard this, too. THe weight savings were canceled out because of the loss in aerodynamic drag. Thanks for your correction to this video.
Ages ago I heard that they were faster without the paint.
Spot on comment, you are correct!
Don’t underestimate the effect of finish. I read the memoirs of a German nightfighter, who wrote it seemed unnecessary for him to change away from the BF110 to a more potent plane like the HE219, as he had his plane waxed, panel lines fillered and glossy finish, which made his plane, even with the antler-like antennae, 40 km/h faster. The same thing I heard from my WW I fighter ace grandpa, who said after 3 victories or so your chances of survival rose, as you got better planes and more important, aircraft mechanics.
@@carlwear1249
No, this video is wrong, painting an aircraft as large as a B17 only added 75 lbs to it, not the "hundreds of pounds" claimed in this video and by so many other sources, the mere addition of 75 lbs was more than offset in the reduction of drag from the paint smoothing over the lap joints and rivets on the exterior of the aircraft, a painted B17 picked up 4 knots of speed and about 200 miles of range from the reduction in drag.
In 1944 the US military had the aircraft manufacturer's stop painting aircraft at the factories because it was too time consuming and caused choke points in production and delays in the delivery of aircraft, after that whether or not they were painted was left up to the individual theater commander's.
Corrosion resistance also has nothing to do with it, well before WW2 a special aluminum sheet called Alclad which does not corrode was developed for aircraft and other things that need to be made of aluminum and have corrosion proof properties.
Pure aluminum does not corrode but it's about as strong as clay, when alloys like copper and tin are added to it to give it strength it also makes it susceptible to corrosion, Alclad is an aluminum alloy sheet that has a pure aluminum coating on it, it's strong like regular alloy aluminum but is also corrosion proof, painting military aircraft never had anything to do with keeping them from corroding, it was strictly for camouflaging.
You note it was not silver paint, but this wasn't always the case. To help achieve the P-51's laminar flow wing characteristics, the wings were filled and sanded completely smooth, and then given a coat of silver lacquer.
This is true, you beat me to it. It is the reason why the fuselage of P-51 could be a patchwork of different shades of "silver" depending on the state of the bare aluminum panels, whereas the wings were usually a uniform silver color.
Absolutely correct. Apologies for my post restating this info.
The wings of otherwise unpainted F-104s were also painted to maintain smooth airflow. The upper surface was painted gloss white and the lower surface a standard USAF gray color.
I recall my Grandfather talking about something similair. I was very young but remember him talking about his P-51 air crew buffing his plane with some kind of wax. He spoke about getting more fuel efficiency.
There were some extremely wild paint schemes used on USAAF bombers besides the normal olive drab. These were the assembly ships or "judas goats" used to assist B-17s and B-24s in getting organized into combat box formations quickly with minimal use of fuel and in radio silence. To give the bombers visual clues and instructions, the judas goats were painted in bright stripes or polka dots like giant flying clown cars. They were also equipped with several flare launchers and a generous supply of flares in various colors used to signal the bombers as they formed their combat boxes. Other than flares, the assembly ships were completely unarmed.
Jimmy Stewart (the actor) flew them in WWII As well as bomber missions over Germany
Ah, you mean pathfinders!
@@bartoszp.7798 No, a pathfinder ship has an entirely different mission task. Pathfinders marked targets.
If you want some really wild painted planes have a look at the various Spitfire colour schemes
Notably, the P-51s did have a stripe of dark pain from the front of the cockpit forward to the propeller. This was to reduce potential reflective glare shining into the eyes of the pilots.
Veteran German flack gunner to a new recruit:
"If it's brown planes, it's the British.
If it's silver planes, it's the Americans.
If it's no planes whatsoever, it's us."
lol
My Grandfather was a B 24 crewmember in the SW pacific the 24's he trained on in the states were green,but when they where given brand new 24's to fly to their area of operations overseas they where bare metal. This is totally due to weight savings.
WWII US Bombers did a video that mentioned the amount of distance an unpainted B-17 got over one that was painted. Hundreds of miles and that made a big difference in the Pacific theatre.
Not to mention that the contrails/vapor trails they left in the sky made any camo paint jobs pretty much useless anyway.
Weight-savings was indeed a factor. But when you need to churn out a lot of equipment, time-savings is also a major incentive. Both were clearly important enough to outweigh the maintenance concerns of bare metal. And if you think about it, the US Navy never implemented this. I never saw any US Navy aircraft that was bare metal during WW2.
@@urbypilot2136 Navy & USMC needed the corrosion resistance that a coat of paint gave.
@@glenmcinnes4824 Exactly my point why they never did the bare metal thing.
We had a customer at work that I became friends with. He was a ball turret gunner on a B-17 in WWII. His plane was an early G model with the improved forward guns, but was also bare metal. It was mid in 1943 when bomber raids didn’t go deep into Europe. Their mission was to the Netherlands in a single box of 12 to 16 bombers and they were the only bare metal aircraft. The Germans picked them out as their primary target and they were shot down. He survived and was a POW for about 2 years and after release they had to lay on the ground spelling out POW because of straffing Allied fighters at least once.
b 17 bombers were the old exposed Rivet design and it was found that teh Paint on a B17 helped the air flow. the later unpainted Aircraft lost cruse speed at the same Throttle settings. later Aircraft like the B29 and fighters with flush mounted rivets were faster without paint.
How tall was he?
@@badlt5897 5’ 4” at most. But a very well respected orchid breeder. Their B-17 came from the Wichita plant as he remembered the tail number and found it through a printed resource. He thought it was a very late F model, but the record had it as an early G. Could be the ship’s plate had an error with F already fixed on it.
@@michaeltelson9798 I figured. Most ball turret guys were pretty short or they wouldn't fit. Great story.
The more of these built, the better since the targets could be spread among more planes. The process to produce them was helpful along weight, but also along production. The mistake made in the case of these types of planes, they didn't send along paint and gear to finish the job by the crew on the ground maintaining it.
Wasn't 'silver' it's bare aluminum. And Aluminum doesn't rust, it corrodes. I knew about the weight factor of paint. On the first B 29 prototype it was painted but they gave up on that for all the reasons you said. The US Navy kept their planes painted the three color blue pattern till about 1944 then they just painted them all a dark gloss blue. When you see a squadron or bomb wing in Europe around that time with some painted and some not it looks like a WWII version of Richthofen's Flying circus. Good relevant footage, Well done.
The Navy kept painting their aircraft since the paint help protect the metal from corrosive salt spray at sea.
@@toqtoq3361rust is a specific corrosion product. Specifically it is hydrated iron III oxide. No metals other than iron and steel can produce rust. Only the ignorant claim other metals rust, they corrode.
@@neiloflongbeck5705in common parlance 'rust' and 'corrosion' are considered interchangeable terms.
Beeeecause rust IS a form of corrosion.
Stop being a dick.
Rust is corrosion. Aluminum turns white when it oxidizes, aka corrodes. Why people call it corrosion, no matter what material it is on.
@@johnh2410I was in a patrol squadron 50 years ago and there was a shop that did only corrosion control. Salt air raises hell with planes.
This video answered questions I have had since I was a kid. I am 70 now. I had a P-51 Mustang model with a gas engine that was silver. I never know why until. Thank you very much!
@Brownbear77777 I’d bet my next pension checks that you never had a silver P-51 Mustang.
I bet it was made of aluminum. Silver is way too expensive and heavy.
@@robertwilliamson922 He is talking about a "model" plane, not a full-scale plane, you donut. Did they not teach you comprehensive reading in school? Silver as in color, not material, you goof. Are you that dense?
@@robertwilliamson922 I would bet that he was referring to a "metallised" (chrome/silver colo(u)r) mainly plastic control-line model, and by "gas" he meant a methanol based fuel BUT anyone who played with piston powered model planes back in the day would know what he meant.
@@robertwilliamson922
Back when motorcycle technology and aluminum metallurgy were less developed (30s or 40s ?), a British motorcycle racing group went so far as to inquire around the jewelry district as to the cost of casting heads out of silver, because of its thermal conductivity, to help with overheating problems. They found that in addition to the expense, the alloy level needed to get acceptable strength largely negated the desired conductivity.
Navy planes were much more subject to salt water corrosion, so paint and/or anti-corrosion primer made a lot more sense.
The WET paint, in the can, was 8 lbs. per gallon, but after application, when the solvents evaporated, the dried paint wasn't that heavy. It probably was to save time in manufacturing, and the expense of the paint itself. Still, certain internal parts were painted Zinc Chromate green, and still are to this day. Especially Navy aircraft that are exposed to the salty environment. Thanks for the video. Jon
Interesting point! The internet tells me that dry paint is 60% the weight of wet paint so 8lbs would be 4.8lbs. lol, you made me learn something today, thank you.
Paint pigments are more dense than water. Water weighs 8.3 pounds per gallon. Water has a density of 1 so even though it is denser than the organic liquids used to comprise the paint, the pigments would still be heaviest part of the paint. Certain pigment colors used a lot of heavy metals which made them much more dense; easily 4 or 5 times as much. I think the 8 pounds per gallon applied weight is probably conservative.
@@mmm-mmmBill Lear famously said he'd sell his grandmother to save a pound.
No record exists about how much a gallon of paint used on the aircraft weighed. Contemporary reports stated that with the elimination of the paint, fighters would be “fifteen to twenty pounds lighter” and heavy bombers would “lose seventy to eighty pounds.” One recent study on the subject noted that the paint during this period was undoubtedly lead-based and “probably copper fortified.” A gallon of such paint could weigh as much as 30 pounds, though for aircraft it was more likely to be in the 10-pound range. A B-17 has a surface area of 4,200 square feet and took about 35 gallons of paint to coat. If the paint weighed 10 pounds a gallon wet, after accounting for evaporation the weight would be roughly 300 pounds. Given that figure, eliminating the paint would indeed be a major weight reduction.
Of more limited use was the fact that Recon planes were found to benefit from being lightly painted and then polished to remove any bumps on the skin of the plane. This improved fuel efficiency, and made them faster. The video stats correctly that the lack of paint really did save weight time and money. Money savings may have been the biggest factor in this.
Weight was really the big one. If the plane did not need the paint for protection from seawater it was a huge removal of well over 100 pounds of paint. Skipping the full paint also shaved about 2 days off each planes production. And while skipping the paint reduced costs. It's not really in the ways you would think. It was more it reduced the massive logistics chains needed to get the paint to the plane factories. And it eliminated a point of production bottleneck. The paint was still being made and used. Ground vehicles needed painting. But by cutting the planes out of the paint loop created efficiencies throughout war production.
Painted B-17s actually were faster for a given rate of fuel burn. Likely due to the paint lowering drag from exposed rivets and panel joins
There’s another RUclips video that shows the US Army’s very detailed studies on cost benefit of painted vs non. Pretty good video
ruclips.net/video/420fO_-u0nE/видео.htmlsi=u3lOR9Eh1JHYxdp7
So this guys conclusion is…incorrect
Never heard of that. 5 Grand, the 5000th B-17 Built was bare metal, but, factory workers where allowed to paint their names all over the plane and it was pretty well covered in signatures. It proved to be slower than the other bare metal bombers. So how does paint help? It would if the plane had been smoothed and the paint highly polished, like race planes, but, these where mass produced aircraft that used flat paints for camo.
@@mypl510 Australia had a wing (three squadrons) of Supermarine Spitfires fighting the Japanese over the Northern Territory and New Guinea. The Wing Commander (Clive Caldwell) was always on the lookout for any edge he could get, so as a test he ordered his own aircraft to be stripped of paint and the bare metal waxed and polished.
The end result was that his aircraft was up to 20-25mph faster than any of the other Spitfires - which was A Good Thing - but it also meant that his Spitfire stood out like dogs-balls when he was leading his wing against Japanese Zeros, which from his PoV was not good. Not good at all.
So it was a short-lived experiment. But it showed that if you (a) stripped the paint off and (b) then waxed and polished the bare metal then (c) you got a significant increase in speed.
@@mypl510
See World War II Bombers or Greg's Autos and Airplanes for information on speed and fuel burn. The difference wasn't much but it was there. And when 5 Grand got to a squadron the names probably came off. Just like I doubt Yipee the red P-38 stayed red.
I remember reading a story told by an American ace, I think it was Bud Anderson, who made a comment to his crew chief that he liked the unpainted, polished aluminum look. The next morning, Anderson said that went out to his Mustang and found that instead of the green camouflage scheme he was used to, it was now gleaming, polished silver, and standing next to the aircraft was an exhausted crew chief and ground crew whose hands looked like raw meat from a long night spent using steel wool to strip off the old paint.
That has to have been the same story I've read! Only differences I remember was that he made the comment to his crew chief after it had snowed. Some pilots thought the bare aluminum offered better camouflage over the snow than the olive drab. He mentioned it might be time to go to the winter scheme. Then, the reason their hands were so red was because they used the only paint stripper they had readily available and that was aviation gasoline! Always loved that story
I remember Pappy Boyington writing in his memoirs that he recommended the Marine Corps adopt the bare aluminum scheme. I think his argument is that it would make the aircraft more visible to the enemy and thus facilitate dog fights (!)
Camouflage is important to avoid being jumped from above, when You're in a disadvantage. That's a main reason why the aircraft - camouflage was invented during WWI. During WWII British fighters' camo was changed into grey - green because it was better on higher altitudes than brown - green, when You're flying at 5000m and Your enemy is approaching at 7000m. In the end of WWII the German camo was changed from grey shades into dark grey (or brownish) and green, because they could be jumped at low altitude. Some WW2 US units introduced improvised camo on their shining fighters from the same reason.
I’m posting this before finishing the video, but already know the deal. At the beginning of the war they were concerned about aircraft being spotted, hence, the camo paint jobs. But later on in the war, it didn’t matter as the contrails from thousands of bombers and fighter escorts gave away their positions anyway. It also saved weight, time, and money to send them out in bare aluminum. On something like a Lear 25 like I used to work on, the paint added around 500 lbs or more to the aircraft’s overall weight. On a bomber or fighter, that’s another bomb it can carry, or another 500-1000 lbs of fuel.
I work with a WW2 army veteran. He told me a few weeks before the war ended. The sky was full of bomber planes. He explained it look like a few miles long sheet of Reynolds wrap in the sky Reflecting from the sun rays.
I had assumed that the silver finish was down to weight saving, but it is interesting to hear the other reasons of: not necessarily being required and time saving in the factory, I can imagine that during war time the latter was particularly important.
A painted B-17 was actually faster than an unpainted one. The Army Airforce tested them against each other and it was decided that the paint smoothed out all of the rivet heads and thus made it slicker through the air. The weight claim did not make any difference.
That might go for riveted aircraft, especially big ones like the B-17, but I'm fairly sure fighters like the P-51 were welded because that's more aerodynamic. So there paint would make quite a bit of difference.
later in the war, they decided that saving the weight to improve mileage was more important than camouflage since they had air superority
The weight savings - 200-300 pounds on a B-17 or B-24 - meant that they could carry more fuel or other load for a bit longer range! Avgas weighs about 6-pounds/gallon, so that 300 pounds saved in paint weight meant that they could theoretically carry another 50 gallons of fuel. That 50 gallons is another half-hour of fuel - enough to fly another 70-90 miles.
The P-51D had the wing panel joints, rivets filled, sanded smooth, primed and painted silver to give the smoothest surface. Canvas covered elevators were also painted. Underside of the wings had one coat of filler. Just google "P-51 wings painted" and you'll see.
It seems the silver planes were also sending a message. Recently I saw a story recounting German Luftwaffe men examining a shot down P-47. They noted it's gleaming finish and the fact that the plane showed almost no wear indicating that it had recently arrived at the front fresh from the factory. They compared that new fighter to the worn and repeatedly repaired planes they flew and they understood what it meant.
The German soldiers had a joke about aircraft recognition in the last year of the war: "If they are green, they're British. If they're silver, they're American. If they're invisible, they're German." Imagine demoralization so bad you use black humor to describe it.
Funny!
That's actually a really cool flex. America is like "yeah, we know you ain't gonna come get us, so we aint even gonna try and camouflage our stuff".
P51s were used as bomber escorts throughout the European Theatre. Silver made it easy for bomber gunners to recognize friendly aircraft, and minimize accidental shootings.
My Pops was a WWII P51 pilot in the Pacific, I asked him the same question and he said the Mustang was to fast to paint .
One last bonus is that the paint not used to paint the planes could be used elsewhere, or less paint needing to be purchased/funds going somewhere a little more important than paint.
They stopped painting aircraft camouflage when they gained air superiority. Cost savings and weight were also a factor.
Early P-47s entered the war painted olive drab but by the end, were left bare aluminum. Even early B-29s were painted. Mustangs re-designated A-36 Apaches were painted
That's pretty much what I was told growing up. For the last year or so of the war: 1. Allies had Air superiority, 2. Streamline production, 3. Save the taxpayers some money.
RAF and Friends had very few unpainted planes
Awesome content - please keep it up. I've always wondered about the silver finish, now I know, thanks! ✌🏼
A painted B-17 was actually more aerodynamic than the unpainted version and used less fuel. A B-29 was bare aluminum since it used flush rivets and the skin was put together in a butt joint, not an overlap. I want to say the same goes for the B-24 but I would have to do more research on that first.
Silver planes weren't only unpainted aluminum. On the silver P-51s, for example, though the silver fuselages were bare aluminum, the laminar wings were not. The were puttied to remove seams and rivet dimples, and then painted silver.
This was also why NASA stopped painting the main fuel tank for the shuttle - to save on weight.
Parts of the P51 wings were filled and indeed painted silver to make the surface more efficient. The fuselage was left unpainted
The brits did not like silver because they needed every plane to last as long as possible. Also their experience of the war taught them not to make a bigger target for the enemy. The US had massive resources and did not really care about losing planes as they had the men and the money to replaced them, the British were the opposite. It shocked the brits how the US had a complete disregard for their service men in the air war over Europe.
I met the Benjamin Moore chemist in charge of green paint from 41-45 in Albuquerque. The industry was overwhelmed and any cuts were appreciated.
The 72 lbs (not 720 lbs) of paint on a B 17 reduced drag and increased speed by 3 mph.
This is true. The paint filled all of the little nooks and crannies in the uneven surfaces of the aircraft. The paint also "raised up" the surface of the aircraft so the rivets didn't protrude as much.
Thanks for that,@@OneHitWonder383
I love straight forwardly presented videos. Thank you!!!
A silver P-51 Mustang really looks cool😎
I’ve never seen a photo of D in paint. They must exist but I can’t think of any. B’s were olive drab but the D was the thoroughbred.
@1:47 Nice picture of the B-24 Willow Run Plant in Ypsilanti, Michigan. Otherwise, even though the late-war US aircraft were silver, they still had to paint the forward cowls to eliminate the glare which would blind the pilot.
The camoflauge of the aircraft wasn't just for the time they were parked on the ground, but so they'd be more difficult to detect from above while flying (probably far more important). Clearly Navy aircraft weren't painted with blue on top to make them harder to spot on a carrier deck (or even while on land based airfields) but against the blue of the ocean while in flight.
The Navy in the Pacific operated at much lower altitude than the planes in Europe. Most combat took place around 12000 to15000 ft. Europe was 20-30. Hence the blue paint.
@@karlhumes6110 Combat has literally nothing to do with it. Once you're in combat, no amount of cam is going to hide you as you're way too close. The point is you want to hide from interceptors at high altitude while you're closer to the ground/ocean than they are and on your way to a surface target. Fighters require less cam for this reason but still don't want to be spotted from above if possible. A silver Mustang would've stood out on a sunny day like a search light while it was down on the deck strafing ground targets, but they weren't worried about it by that stage of the war.
Always wondered, but never gave it a lot of thought.
Thanks for clearing this age old question up for me.
Great video.
I had heard that towards the end of the war as the allies had attained air superiority the powers that be decided it was no longer necessary to try and hide behind their camouflage but wanted the enemy to come up and fight with them. If they could be defeated in the air that would help hasten the end of the war.
they came out with the ME-262, the first jet acft. but it had a short airtime. make a few passes then back to the barn.
There is a bitter truth to this. A significant aspect of the SBI was that it drew German resources away from other areas. The Allies we’re picking a fight for the fight’s sake, damage on the ground aside.
Air superiority made it so they can save weight by not painting them. Modern large aircraft use over 1,000 pounds of paint.
I was surprised how well silver planes actually blend in with clouds and the sky when playing IL-2, its really only an issue if the enemy is above.
I'm a private pilot, and once I was sharing the pattern around an airport with a natural metal DC-3. At certain angles, the skin reflected the green of the ground vegetation, making it difficult to keep track of its position.
@@petesheppard1709
I saw a pilot doing his yearly polishing of his bare high wing. He told me that it was difficult for those on the ground to see it on approach, as it reflected the sky from around and behind its slender frontal profile.
Brilliant, well done!
Tusky airmen, may we never forget their sacrifices.
Very insightful,I never thought about this 🤗👍👍!!
I saw that one pilot said ( joking, I think) they want the Germans to see them so they wouldn't miss the fight.
Not all of the Mustangs were, but yeah the main thing was getting aircraft to the front line.
US Navy aircraft were painted throughout the war, I imagine to help resist saltwater corrosion.
That is true, but there were some other reasons: 1) combat took place at a lower altitude (consider torpedo bombers, which operated "on the deck") so blending in with the blue of the sea was still advantageous and 2) when returning to the carrier you would often have to really throttle back to conserve fuel, which left you vulnerable to being "bounced" so, again, blending into the sea was a good idea.
To speed up production. Plus the paint actually caused drag.
It wasn’t the silver frame, it was the silver outer skin…
a true fact, the paint actually decreased drag especially on the B17, but the war was almost over and never went back to painting them. the paint would fill in seams and rivets which decreased the drag while not painting them increased this drag and increased fuel consumption.
Es fehlte der Lack um sie an zu streichen? Mein Vater hatte einen Karabiner in der Wehrmacht der wahr nicht brüniert und das Holz nicht abgedunkelt. Es fehlte an den Mitteln das zu tun im Herbst `45.
Ich glaube nicht, daß Dein Vater im Herbst '45 einen Karabiner hatte, ob brüniert oder nicht!
The Allied strategic bombing campaign contributed greatly to the Axis shortages of bluing, paints, and other petroleum products, as well as aluminum, molybdenum and other chemical additives.
Excellent. Liked. Subscribed. TY!
4:10. Tusk KEE gee airmen
If Michael Jordan flew P-51s in WWII….and brought all his friends ….. Tuskegee Airmen
My favorite paint scheme is the one they put on a B-25 Mitchell bomber as General Dreedle's plane in the Catch 22 movie. it was a sort of beach sand color with general's flags (like you would see on the front of a limousine) and white wall tires.
Especially with the heavies, not painting them saved weight and every pound saves means an increase in range. Often the Mustang and Thunderbolt pilots used to paste wax their aircraft to make them more "slippery" and got a few extra knots out of them.
I’m a former aircraft mechanic and worked on Lear 25’s. Besides doing that, I would polish the nacelles and intakes of the engines to a mirror finish and the pilots picked up about 10-20 knots and increased range due to less fuel consumption.
I would have guessed that silver would reflect the ambient colour of the atmosphere around, changing from dawn til dusk, making it harder to spot. Thanks for the video
The sheet aluminum on the outside panels are pure aluminum bonded to the main thickness which is not pure but alloy aluminum. The base metal of alloyed aluminum was subject to corrosion while the thin layer of pure aluminum protected the base metal because it did not corrode.
Just one more step in explanation. The pure aluminum ‘akshually’ oxidizes very readily, but the resulting oxide is a very hard, tight layer that seals the bulk against further corrosion. When I said very hard, it is; it’s the same stuff on aluminum oxide sandpaper, and ruby.
When they were coating the near perfectly misground Hubble main mirror, they sputtered the aluminum on in a vacuum chamber. They then had to immediately, in a very few minutes, coat it with a protective coating, of a fluoride base I think, to prevent the residual oxygen from reacting with the reflective surface and producing infrared absorbing oxide to negate one of the prime design goals of the telescope.
The Enola Gay was actually PAINTED silver. This was so that it would reflect more radiation....it was NOT left bare metal!! Her fighter we're also painted silver....
There is a bit more to it as p-51s/47s had a high quality of manufacture where other types had less. The silver b-17s were slower than there painted counterparts because the overall drag from panel gaps which would be otherwise filled with paint. ruclips.net/video/420fO_-u0nE/видео.html
Not so much gaps. The B-17 was built using overlapping panels, common for the time when it was developed.
good show, many thaks
The weight save was critical because it allowed Allied planes to fly deep into Germany from British bases. I think that may have inspired American Airlines to have a natural metal finish on their airliners until last livery change.
He is wrong, paint weighed 72 lbs on a B 17 ,it streamlined the rivets and increased speed by 3 mph.
With modern airliners having more and more composite construction, if you'd leave them unpainted you won't get a natural metal finish anyway. Airliners are often painted white, because it is highly visible (the opposite of camouflage!) and being reflective it helps keep the cabin cool.
@@jbepsilonand not just the cabin but the structure too. This is why carbon and glass fibre airlines and gliders are predominantly white, even in the cloudy UK.
Superb video!!
There was actually a sizeable difference in performance. A polished metal airframe could add 15-20 mph to the airspeed. British used the S Type aircraft colours that replaced the previous Matt types. The S stood for Smooth and they were high gloss producing a low drag finish increasing the aircraft top speed. At the same time 'whip' antenna replaced mast and wire and as were flush riveted.
i had not thought about it until i saw your video. thank you.
there is another channel that said that the unpainted B17's were slower than the painted ones and used more fuel to keep up, the painted ones had minor flaws in the planes panels filled in with paint and that added to the performance
Why are you consistently referring to silver coloured aircraft, it’s polished aluminium (GB) or aluminum (US). If you produce content, at least do your research properly. A lot of modern aircraft still have polished pure aluminium clad alloys heated areas. BTW the P51 wings were treated with filler and painted in high gloss „silver” grey. And British aircraft were sometimes painted with a aluminium pigmented paint.
Didn’t watch the whole video before commenting?
Its because the U.S grinded on the Pacific server before smurfing on European servers, reaching level 44 and unlocking the prestigious skin.
side note: they should patch this exploit for the next update or just revamp the whole system for the next release.
All I know for sure is that after I polish my aluminum Grumman canoe, it's faster and has a longer glide - the time between the last stroke of the paddle at full speed, til the boat stops. Friction is the enemy of efficient movement through any mass, no matter the speed. Even if it's just 3mph.
Great vid !!!
By 1945, the US was running short on Olive Drab paint (along with a lot of other things) and by then, the numbers of American aircraft in the air vs. axis aircraft (German and Imperial Japanese) nullified any significant reason to camouflage them.
The Lone Ranger Rides a horse named Silver...
I've been wondering about this issue all my life. Thank you!
I thought it was for reducing unnecessary costs and expediting the manufacturing process, which I guess was a part of it.
never really thought of the weight part... very cool
Good video! My grandfather flew P-51Ds against the Japanese toward the end of the war. His aircraft looked like some of the ones in your video: base silver with black on the engine cowling, red by the prop and on the aeleron. And a single red stripe at an angle down the sides.
Tbh, I've always just thought it was due to his unit's SOP. Never realized it was weight and money savings- makes sense though.
He never got shot down, so I guess it worked successfully for him. Lol!
I always wondered if it was for dog fighting purpose. aluminium would reflect light and throw off an enemys aim.
Never gave it much thought about silver
finish on the planes till I saw this video,
very enlightening...thank you.
In a definitive official history of the spitfire development, (The Spitfire Story by Alfred Price and Jeffrey Quill), tests were shown to have been undertaken as to which superficial modifications were worth undertaking to improve performance factors. I think on a mk.v model. These included rear view mirror removal, application and position of flush riveting, curved front windscreen, and the gloss polishing of the standard matt paintwork, plus careful attention to filling panel gaps. All of these added about 18mph to the top speed if I remember correctly, with the gloss finish contributing the most to this improvement. Some of these detailing were subsequently included into production procedures.
Those tests were done well before the Mk V, on the pre-PRU photo-recce Spitfires back in '39 - these had their panel lines chalked flush , and paint polished for speed
I've seen videos and interviews of WWII pilots and maintenance crew and the main reason was they would use camo colors during mid spring though early fall and then remove the paint during Late fall to early spring. Because Europe is such a snowy place during winter, silver tended to blend in with the snow and make it harder for enemy aircraft to see them from above during flight. camo colors had the same effect during mid spring to early fall when there wasn't snow on the ground.
No you didn't, and that had absolutely nothing to do whether they were painted or not.
The reality is and what the creator of this video obviously didn't know is that in late 43 they quit painting aircraft at the factories because it was too time consuming and caused choke points in production and delayed delivery of the planes, theater commander's were screaming for aircraft and they told the high command they didn't care whether or not they were painted as long as they had wings and could fly was all they cared about, so from that point on whether or not they got painted was entirely up to the theater commander's and was to be done by the units that got them if they wanted them to be painted, they never had any problems seeing them from the contrails they left behind and you can't hide hundreds of 4 engine bombers or their escorts, the Germans had radar and knew exactly where they were at, the camo paint on the top was because originally they thought that US air bases in England might get bombed which is something that as it turned out never happened anyway, the flat gray on the bottom was because they thought originally that it'd make it difficult to see by AA crews but as that turned out German AA guns had radar along with the fact that with hundreds of contrails in the sky everyone from Sweden to Switzerland could see a formation of 300 B17's and their escorts, many units never bothered to paint them after receiving them when the started showing up unpainted and some simply did it become some military commander's being the way they are wanted every aircraft in their unit looking the same.
Ground crews had plenty to do in between missions like repairs and replacing engine's along with preping aircraft for the next mission, as it was they worked around the clock keeping them flying and had no time to strip the paint off of hundreds of aircraft.
Quit making things up.
Some great footage here.
I've been a fan of warbirds for years, made a few models of them when I was younger, and often wondered about the silver ones, even thinking to myself: "this would be lousy for camouflage", but today I wonder no more! Thank you so much for answering a question that I had wondering about for years! The fact that not applying paint would make the aircraft lighter and therefore faster seems so simple, yet I never even thought about it before!
The same for me.
Six minutes to answer something that required ten seconds.
Thank you for getting straight to the point! That was very informative without the clickbait other videos give these days. Yes, paint is quite heavy, which is why Eastern Airlines didn't paint their commercial airliners.
Very interesting video
Glad you enjoyed it
The maintenance on a bare aluminum airframe is actually much easier. It’s easier to spot problems than when they are covered with paint. They are also much easier to keep clean. A clean aircraft will allow a higher speed as well.
You forget to mention the "We pimpin' out here" factor. My great uncle piloted B-24s wearing a purple fur coat w/ matching hat and feather.
The B-24 or your great-uncle?
I remember reading many years ago . About a P-51 pilot that mentioned his ground crew kept his bare aluminium plane well waxed. Said it added a bit of speed . I would imagine reducing corrosion resistance too.
Wax / oil on bare metal would add to corrosion resistance, not reduce it.
The waxing smoothed the surface, and therefore improved the airflow over the wing. And the P-51 had a laminar-flow airfoil design, so keeping the airflow smooth was a very good thing.
The British tried very hard to get semi-gloss paint that was hard-wearing, because the alternative (matte paint) added much too much drag.
@@SevenSixTwo2012 Most of the exposed panels of the P-51 was aluminum, so corrosion from any wax isn't really going to be an issue.
The much bigger problem was corrosion caused by electrolysis whenever aluminum sheets are riveted onto steel frames.
@@johnreynolds7996 Very, very little steel in a p-51
@@Mach1Greeble Oh, sure. But "every little" is not the same as "none".
I've heard of The Tuskegee Airmen but never heard of the Tusky Airmen.
Perhaps the AI speech synthesizer didn’t know if the “gee” was pronounced with a hard g like “get ” or a soft g like “gin” and so decided to play it safe and leave the syllable out altogether.
Wasn’t sure why. But now it makes sense. Thanks
thanks for the history lesson!
Who knew that paint is so heavy? Great video!
It’s really heavy wet in the can, but much lighter once the solvent vehicle dries away. Eight pounds a gallon is just what petroleum spirit weighs. The pigment must weigh almost nothing.
identification of friendly or enemy. If a plane is silver its an allied plane if not its a enemy
And that is why the RAF were reluctant to go anywhere near US bombers
First thought was that it had to do with blending in - sky or ocean (blue)...but cool to learn how much sense it made to not add the additional weight.
Subscribed - good channel!
Thank you for this video. I also pondered that. I figured that they simply didn't bother, but i didn't expect that it had more adwantages