Avoid the 'graveyard turn'-a safer way from base to final
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- Опубликовано: 15 авг 2023
- The base to final turn is an aircraft accident hot spot, and those accidents are usually fatal. Yet the manoeuvre is usually depicted as a ninety degree turn that, at low altitude and low airspeed with a precise aiming point, is potentially very dangerous particularly if the pilot becomes distracted. In this video I demonstrate how the danger arises and show how it can be avoided.
I am not suggesting that the pattern I describe will be ideal for every situation, and variations may be appropriate according to circumstances; I am trying to point out the dangers of a sharp base-to final turn that is typically undertaken at low level and low airspeed where there is little margin of safety and offer a solution to consider. 
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Very nicely explained. Video not too long so as to keep viewers interested. Thanks 😊
Thank you, I am happy that you liked it.
I've had five basic flight instructors. Two of them were military pilots. Two were civil pilots. One was an aerospace engineer for NASA. The two military pilots taught the smooth continuous turn to final. The other three taught me to do tight, precise, box-like turns to final from a 90-degree base. The military pilots flew hundreds of sorties in Vietnam, and afterward, both flew for the airlines. The others, by comparison, were relatively low-hour commercial pilots.
I learned in the military.
We always did one continuous curve.
I agree, I like the keep my turns oval shaped, prevents over banking and over shooting finals, and much less aggressive for nervous passengers
Military flyers use continuous descending base to final turn (curvilinear) withe the nose always down - much much safer than square pattern. In light plane with power at idle or near idle results in no to minimal traffic pattern stall risk do to continuous nose down attitude all the way to flare.
exactly...but doesn.t answer why people are pressed into tihht square patterns everywhere out of " good customs " or" we have done it always like that" , or also doesn.t explain why GAs are always pressed to risky approaches by some "standards" ...maybe so eone should start to think about that in the higher rnaks instead of downregulating GA even more...
And if you happen to encounter a sudden crosswind on that turn onto final it can complicate things as it did for me as a newbie second solo flight. And to com-locate it further I was landing int the east Texas big thicket with 50 ft pine trees at the foot of the runway that I had to pass over, before I could get down to the runway. Stall warning sounded but I was able to recover, I don’t know how, and made it down safely.
As a CFI It makes sense and in practice most turns are more smoothed than squared. The issue is getting DPEs to accept the technique.
FAA already approved the technique and encouraged pilots to use it. so DPEs can pound sand if they don't like it.
Intelligence must be applied to be useful. The around-the-barrel approach, as you suggest, makes good sense and greatly reduces the potential for disaster. So, why not use that method when possible and reduce the risk.
@@SoloRenegade ĺp
One reason for the squared pattern is for traffic identification and avoidance. I tend to round out the base to final at towered airports with on duty controllers but level the wings on base to check for any unannounced traffic on final at nontowered airports. I fly an RV-7 so it has the usual low wing blind spots.
After finishing square approach instruction and license exams for all of the following aircraft types, I defaulted to a constant turn approach which just feels way safer to me. Paragliding, hanggliding, sail planes.
You are exactly right. If you look at any Navy NATOPS manual it shows the oval flight pattern.
This was brilliant. Short, concise, dramatic enough to get the attention and the point across. Some rules are there for a reason. Liked and subscribed.
This is the pattern I typically make. The more tired I am, the windier it is, etc... the more likely I'll use it. I do square the pattern for traffic avoidance. You simply can't see everyone when turning continuously. That's a problem. I've experienced the annoying straight in pilot, the wrong traffic pattern pilot, and the "I fly a giant pattern" pilot while on base leg to final.
On base leg I check my gear one more time, look for incorrect pattern "members" of society, and then turn final. I try to make my pattern wider to avoid this being a problem in the first place. Also, I NEVER step on the rudder pedal that's near the ground... I'll even slip a little by stepping on the skyward pedal on base to final. I even pull my foot off the inside rudder pedal. Can't spin if you don't stomp the pedal. Just a couple of glider tricks in our bag to try to stay alive.
I've long thought that square corners in the pattern just add to the task load, but never felt it was my place to declare such (I'm a geologist). I really like the philosophy outlined in this video. It sounds like solid reasoning to me.
I started out flying GA then was fortunate enough to fly fighters for the USAF. Since then I have always done the continuous turn to final. The only thing I do different is at 90 degrees through the turn I quick roll out to check for traffic on the staight in approach. Cessna is not as critical but when flying Piper, Mooney, or light twin (low wing a/c) this is a critical safety check.
I've been doing the curved right base to final in my Robin for years, and now adopt this on all base to final approaches. It is much safer and that to my mind is all that matters.
In the C172 I always try to keep at least 70 knots on my downwind to base and base to final. I was also taught to introduce flaps into these two turns. Flying coordinated was always drilled into me during training, and I never go past standard rate turn. The rounded turn does seem safer though.
The problem arises when the pilot is distracted (perhaps by weather, radio calls, traffic). That's when flying within a wider margin of safety should help..
That's the way the C150 Landomatic worked.
I was taught a 90 degree turn from downwind to base but do a smooth turn to final starting it out ‘early’ with a little bank and making it steeper if needed to intercept the final approach course. Essentially just making sure you don’t overshoot in the first place
Great video. I’ve been doing this since 1979 when I was taught this by an old tailwheel CFI on a grass strip.
Airline circle to land and Mil do the ‘continuous’ , far safer, just check for straight in traffic very carefully. There is no ‘stall speed’ , only stall AOA, a wing can stall at any speed if critical AOA (G) is passed (usually 14-16 deg) sharp turns need sudden power additions, so torque / prop wash comes in as well.
I was taught the squared approach for two reasons. It's what expected at the reasonably busy Class D airspace that i did most of my training in . Also, when one leveled out it made for better traffic avoidance in the pattern. However, I do like the carrier approach for the exact reasons you talked about and would like to see it become the standard taught
You dont need to level the wings to check for unreported traffic on final if ATC did that for you.
Not only that but teach and preach against straight in approaches, if you're late to the party, you gotta get I'm line.
Great video. An alternative is simply to extend the downwind leg and to be further out laterally from the circuit/pattern. Only a little is required to make the turn much safer and make sure the final turn is never more than 30 degrees. Another factor is never to over rudder the turn, even if it means you are not strictly coordinated at the final turn. Also a little more speed can easily be bled off (another glider technique where glilder pilots routinely approach at way higher than v-ref).you can always side slip a little and cut power on finals if needed. Both of these are much safer than a steep turn.
Thank you and I take your point about widening the circuit, although doing so in poor visibility may mean losing sight of the airfield so I prefer to adopt a consistent method and become adept at it.
Also, the increase in stall speed with bank angle applies when MAINTAINING ALTITUDE, which given a fixed airspeed, necessitates an increased angle of attack (more back stick/yoke).
If you're able to accept altitude loss in the turn and not increase angle of attack, you can mitigate stall speed increase with bank angle.
Excellent video, the smooth turn from base makes a loy of sense. so too does choosing a longer final. It gives the pilot more time to set up the landing properly. It happened to me once in a savage 25kt cross-wind landing at Hoxton Park aerodrome west of Sydney, I only realised later that the cross-wind capaciy of a C150 was 12 kts. The long approach allowed me to adjust the aeroplane to suit the conditions and I did not crash. Phew!
"Cross-wind capacity" isn't neccesarily a limit as you found out first hand. Its typically the crosswind that the test pilots believe that any pilot should be able to perform + some margin. Its up to your own skill level and judgement, which you performed well as you were able to walk away from that incident. I have landed a PA-28-181 with a max demonstrated crosswind of 17kts, in a 25kts crosswind with no dramas up at Archerfield in Brisbane. Stay safe out there my friend!
I've been flying my approaches this way since the early 1990's, when I had the opportunity to go up with an old Vietnam era pilot who demonstrated and explained it to me. I demonstrated and explained it as well in a video on my channel a few months back.
I can't speak for power pilots. I'm a glider pilot. In gliders when flying the pattern we need to be continuously checking to see how quickly the ground is rising up to meet us and adjust how much spoiler and/or slip we need to add or remove. We also have the advantage of a yaw string on the canopy in our line of sight to tell us when we are coordinated as opposed to the ball which is down in the panel somewhere. So the way I was taught to fly the pattern is throughout the downwind leg you are watching your airspeed, your height above the field, and your distance laterally to the field, watching the pattern for other traffic, all that good stuff. Then when you make the 90 onto base your entire attention is focused through the nose and yaw string. You are watching the horizon to make sure that nose stays below the horizon and you are watching that yaw string to make sure the turn never becomes uncoordinated. At no point during the turn should you be looking to see where the field is. It's not going anywhere. As long as you keep your eyes through the nose of the aircraft you will not become uncoordinated and you won't stall. Thus it is a safe maneuver. Then once you are straight and level again you go back to monitoring airspeed, altitude, and distance until you get to the base to final turn where you once again focus all your attention through the nose. So if your goal is to focus 100% of your attention through the nose in a low level turn, you are much more likely to succeed at that objective if you are making two quick steep turns than you would be if you are making one continuous shallow banking turn throughout the entire base leg. In that case your attention is inevitably going to get diverted to where the field is at some point during the turn.
Thank you for your comment. The point of the video was to try and highlight how a danger might be mitigated by giving the pilot a wider envelope of safety at a phase of flight where margins for error are narrow (low and slow and in a turn) and distractions (such as weather, radio calls, other traffic) or misjudgements (such as of a tailwind on base leg) can result in disastrous mistakes. Making a turn with a fairly constant, mild bank angle enlarges that envelope of safety compared to a tight base-to-final turn.
Well done ... I think the 1 reason so many students are taught the box circuit is that it gives you time to get cleaned up ..airspeed ..flaps ... rate of decent ..attitude . ... visualisation of the landing point. As you get more experienced you can get better at doing this closer in. We are talking 500 hours of flight time here for a commercial pilot. If you don't fly often enough you won't get the "Hands and wrists" to fly this. No 2 is a busy airport circuit for separation.( as mentioned below). However I completely agree with you. I have a Cessna 180 that can use 300meters to take off ...but I always go full-length and 20 deg flap so if I have an engine failure close in I can do the impossible turn back and a curved finals means you can make the angle tighter without landing short if you have an engine failure.
After getting my private pilot and then flying by instruments, I have come to prefer the "standard rate turn" especially if I have a passenger with me, easier on them and much safer, so this fits perfectly with that approach.
I have maaaaany flight hours in model airplanes, I have had sporty flights in LSA and I have also flown in military Sea Harrier simulator. In all of the above, proficient and I have always flown and landed the way it is explained in this video. It is intuitive, smooth and safer.
Then, I started getting my LSA flight license and I also started doing these damn squared circuits. There are several reasons:
- In all the theory and internet, you find squared circuits.
- The instructor (even though he flies sporty too) kind of did the same to highlight the legs when teaching the lessons.
- Although not always, I developed a tendency to do those to show I was “in control” and I was never corrected by him.
However, the moment I am told “do what you want with the plane”, I am back flying the way I have always been, whether it is practicing dead-stick landings, mid-field emergency landings, sporty flying around or just on my own. It is overwhelming to see how easy you get influenced by bad habits that are not even yours originally.
Thanks for the video and rising our awareness!
Absolutely, it’s the right thing to do. Trying to make these military perfect square turns is ridiculous. Better a continuous gentle turn from downwind to final, just like you say.
Did the square turns come out of WW2 training?
All the beds and spittoons shall be lined up perfectly straight.
A thousand pilots died in training in WW2,,,,some probably doing the square turn.
Continuous Rate Turn onto Final when using short strips is a real boon. It's an additional safety too if flying old open cockpit with no forward vision. It allows constant monitoring of position relative to R/W threshold. A lot going for it!
Thanks for sharing Steve
Interesting. I learned this from my CFI but it was the "engine fail in the pattern/circuit turn". Starting with the "standard" it became a gradual conversion due to constant "what if you engine fails now? what now? and now?" and so on. The result was also far less overshooting. Frankly, by now, I also have no idea why we still have an obsession with 90 deg turns - and apparently in certain aircraft it's become a real killer: pilots transitioning from your Cessna Landomatic to something like a sleek Cirrus are notorious for overshooting and stall-spinning on base-final. PS: before someone brings it up: yes, spacing become an issue, but only if you have "mixed use", with some still flying rectangles and others ovals.
This is how I have flown my pattern for years. The rectangle pattern never made sense to me because of everything that you said. Great video.
I always teach a gentle turn too. It is a turn into wind though. I feel the downwind turn is the one to watch in terms of maintaining airspeed over the inner wing. Make all turns as gentle as possible close to the ground. Avoid steep turns unless for avoidance. Thanks for the video, good advice.
This is a superbly comprehensive description of the dangers. 😊
Thank you!
While I understand and somewhat agree with your point, this method doesn’t allow for the normal traffic avoidance procedures as it leaves a large blind spot beneath the aircraft. The rectangular pattern is rectangular for scanning and collision avoidance purposes. If I’m in a constant turn like that, the fuselage and wing (if in a low wing) could very easily hide an aircraft beneath it. I think it’s safer to just fly a normal pattern at airspeeds, bank angles, and load factors that won’t produce a stall rather than leaving a blind spot beneath the aircraft.
On top of this, extra emphasis should be placed on go arounds and stable approach criteria.
If everyone is flying at the proper circuit height then surely they should all be at the same level and if everyone practised the curved approach then there would be no conflicts at that level. Of course the vast majority of base to final. turns don't result in a stall, but the few that do, often when the pilot has become distracted by other traffic or radio calls or weather, are almost always lethal, so I prefer to mitigate the risk.
@@pretavol the issue is the pattern is a dynamic environment where everyone has different speeds, performance, and pattern entires. Where I fly there can be everything from J3 Cubs to E175s at an uncontrolled field. I could very easily see a nasty near miss or midair happening from something like a Piper Cherokee colliding with a jet on a straight in approach because it was hidden beneath the wing the entire time.
I’ll meet you halfway and say a nice big sweeping base to final turn after leveling out for a few seconds on base would work well for keeping load factor under control while still allowing for scanning and collision avoidance. With that said, I’d advise against posting videos promoting procedures contrary to common practice as this can create unnecessary confusion and lead to a dangerous environment.
@@hobie1613 Roger. The point of posting the video was to encourage sensible debate on a matter of safety, which it has, and I see a consensus. I am not suggesting that any particular routine is optimal for every situation.
All sounds right to me. With a high wing power aircraft, I will turn 90 degrees from downwind to base. I want to get on base quickly, so that I can look for other traffic on final. However, on the turn to final, I round it off with a shallow banked 90 degree turn so that I can always see the runway (wing does not get in the way.) I use the same technique for a low wing glider. For a glider, I think it is more important to see the threshold sooner (and adjust the turn rate toward the runway) to be able to gauge the height and distance (especially if wind reduces the ground speed significantly.)
Really helpful. Thank you, esp. for the excellent visuals.
Thank you and I'm glad it was helpful!
very good video, thankyou for sharing this . its a lesson i think we should learn early
I've always been told that the crosswind before final is to check for other traffic, especially with a low wing... but I like the continuous turn from downwind to final, with a brief wings-level 'pause' on crosswind to check for traffic and announce turn to final
I was taught to fly the “carrier approach” starting with my very first lesson in 1965. I’ve flown my approaches that way ever since.
You mean a 500 agl Power on full flap Short Approach? With power all times.
A hybrid version is to fly downwind a little bit longer and then turn more than 90 degrees towards the direction of the airport so that you can intercept the centreline at 30-45 degrees and the final correction into final is just a gentle bank. It also has the advantage of much more precision in an accurate line up with the centreline.
Thanks for your comment and yes, I agree: the point of the video was to highlight the danger of a sharp base to final turn and how this danger could be avoided. Flying a continuous curve from downwind to final will not always be appropriate although I prefer it where the situation allows.
The reason this is not taught is simple. It’s not in the syllabus and instructors MUST teach the course material. Only way to change this is get the regulatory bodies to change GOODLUCK.
Also this may work in low traffic patterns like regional and county strips but in heavy traffic patterns L&R parallel runways a good square pattern works well if you don’t turn to early on base and crowd the pattern the turn is not that dangerous this really only happens if overshooting. Be Safe
A concise and well-explained video. I can't disagree with anything you have said here. I often find myself wincing when flying with another pilot who appears to favour this sharp base-to-final turn followed by a longer final. I prefer the method you outline here- mainly out of laziness and preferring to cut the corner - straightening up to the final approach course only within the last NM or so. The safety argument for doing so is compelling as well. I should add that I'm based at a radar-controlled class D airfield, so checking for traffic on final is less of a concern when at home. I see the argument for checking the final is clear before turning on,....
I personally do what this video shows when doing a constant turn to a tower-assigned heading, (or squaring the upwind-crosswind-downwind-base when staying in the pattern), then purposefully start the base-final turn early. I’m usually doing the final turn around 15-10 degrees of bank. Then, if I “overshoot,” I’m just “closer” to the standard bank-angle, but never beyond it.
I was reprimanded once by the head of the college flight school once for “not making a square pattern” (the base-final turn), I complied-ish, but thought “I’ll never be caught dead doing a perfectly standard-rate base-final turn” because it’s just dangerous. The statistics show that pattern instruction doesn’t allow for a “bad day.” Overshooting would never be an issue if you started before you had to. A “planned” 30-degree bank missed to a 45+ degree bank, 10-15 knots slow, with a forgotten notch of flaps, and you could be 6-feet-under in a wooden box. No thanks.
It also is just better planning to be able to lessen the turn rate to be wings level exactly when you are on final, with wiggle room for the wind. One time I was landing in a Bonanza with a 50 knot tailwind on base at 2000 feet, with almost calm at the runway. I started the turn a couple miles before I felt I had to and with extra speed for expected wind-shear, worked just fine. (No wind shear surprisingly). Glad I started when I did, because even starting early I didn’t have to go wings-level because of the wind. The landing was late at night also. If I practiced the “square pattern,” I either would have been a statistic, or a couple unnecessary go-arounds.
If I may add my 2 cents. Although your depiction of the bank angle increasing stall speed is spot on, that performance chart is based on "level" flight which you do indeed mention. Since a wing stall is a function of the wing exceeding the critical Angle of Attack (AoA) however, my instant question to ask my student pilot would sound something like, "Why on God's green Earth are you in "level" flight on your descent and approach"? In most light general aircraft, A nose-down attitude, which reduces the AoA, should be maintained once the descent and approach phase begins unless a go-around is executed. Thoughts?
As for the rounding of the pattern, it is the most common way I land. Low wing vs High wing does, however, modify this a bit. Thanks for the video!
Thank you for your comment and yes, I agree: the depiction of bank angle and stall speed was, as you surmise, to illustrate a point but the principle will hold good at a given angle of pitch. It will still be possible to stall a wing in a tight turn even when pitched down.
Nice video! I do this all the time. Much smoother flying. Also keep attitude so that the KIAS remains the same- i.e. need to relax the back pressure on the yoke during the turn. Add back pressure to increase pitch on final to get to approach speed.
Steven:
I am a rather new pilot with 120 hours. I completely agree with your statement. It takes a little distraction to not turn base to final when you have to then overshooting. Even though it happens to me many times, still sometimes difficult to figure out a reference when to turn, I turn and always make sure that I am coordinated (ball centered) but if I overshoot, I do not get crazy, I keep making the turn coordinated and then correct to the other side when needed. I guess that a gentle turn like 15d like you will use later in IFR training is better. Even carrier fighters use it. No wonder. Thank you for sharing that. And like last comment, great video, short, to the point. Good job man.😃
Thank you for your comment and for your compliment! At least in our aircraft, I think that it is just as easy to hold a steady turn as to fly wings level; in both cases the ailerons are neutral (once the angle of bank has been established in the case of a turn) so the pilot can then concentrate more on other aspects of the approach.
great video! thank you for this!
Thank you and I am very happy that you liked it!
So simple - it seems! Great explanation. ❤ thank you!
Happy you liked it!
I started by flying gliders, and doing the method you advise. Since progressing to light aircraft, I was taught the square base to final. I have real difficulty getting it right every time. One time I came in with fuel starvation due to a fuel contamination issue and reverted to the glider way of managing speed, height and steady turn from downwind through base to final. No problem getting it in safely. If I'd have tried the box method, I'm not sure it would have ended so well
Learned to fly in the sixties in a Piper PA-18 and still have the knots on the back on my head from continuous hits from my instructor to check airspeed, needle & ball while doing pattern turns.
Thanks for sharing this info, I’ve been wondering why that turn has to be 90 deg recently.
This is very interesting, I'm in flight school here in Australia at YBAF, and my instructors always have taught me to do not precisely a rate 1 turn but round out crosswind or base, although I tend to level my wings for base sometimes in case I turn too tight or shallow and in order to kind of "reset" the approach in my head, although as someone else said I'm going to use this opportunity now to check for traffic too.
Totally agree.....The AOPA Safety Foundation funds a research project at the University of North Dakota.......the study looked at "racetrack" type of pattern......and the conclusion ws it was safer.....so why is no one pushing for change?
It comes down to timing and understanding what the plane is doing. You have to understand where the wind is coming from and if you have to turn earlier or later. I teach to limit to 30 degrees bank. I don't like the constant turning pattern as I believe you can lose sight of the long final traffic.
Maybe split the difference and just round out the very last turn more than usual....level out prior to that only long enough to get a good look for that traffic, and begin a longer turn to final as soon as you are satisfied. Unless there is another reason to wait after that, it seems logical to me.
I’m not quite understanding, and many also say the same as you about losing sight of long final traffic, but I don’t understand how.
At first I was just thinking you will see absence of long final traffic in continuous turn also for most of it, or the first half of the turn, so isn’t that good enough? but then thinking you all mean if you do see long final traffic that you are monitoring how far away it is at all times. But if it is close enough to where you need to monitor, 1) isn’t it up to the final traffic to adjust? And 2) if that close isn’t that cause for go around?
Trying to understand the concept.
The reason we don’t do this is we were never taught to do this, in fact base leg was the time to introduce 1st stage of flap so it’s a trigger for something..
Interesting. I passed my check ride in 2000 but have only recently returned to flying and completed my flight review. The first time I (recently) flew the pattern, I did square off on crosswind. However, my downwind to base to final was instinctively rounded. Which is what I continue to fly.
Makes perfect sense to me..
Great video. Thanks
Thank you and I'm very happy that you liked it!
I got taught _"Can always loosen turn by line of sight",_ since tightening is a bad idea!
p.s. Case 1 carrier land is, IIRC, much like what you recommend.
My flight instructer was ex Royal Australian Air force...no 90 degree turns when I was learning to fly
The box pattern needs to die.
After 5000 hours as a KC-130 flight engineer watching thousands of touch and goes - or smash and dash - landings using the Navy pattern; I flat out rejected low time instructors trying to get me to fly a box pattern.
I taught them the Navy pattern. Got my PPL in 41 hours.
I learned to fly on an RAF University Air Squadron (UAS). My instructor had me fly constant rate curved approaches (and I can't understand why rectangular circuits are still used by others). I'm keen to hear the experiences of other UAS students over the years please...?
800ft 80kt, downwind to land call. Checks
Begin turn
Call, looking for 600ft half way round at 75kt. Adjust bank for centreline
400ft 65kt aligned on runway centre.
Bash it down on the numbers.
Make tea for QFI.
I am a military trained current private pilot. I strongly favor the continuous turn to final but recommend aiming for wings level at least 500 feet before the runway to have time to set wind correction. In the military we went wings level above the runway.
I still have a distinct base, but not much of one. I often start my base to final turn 5 seconds after finishing my downwind to base turn. It is mostly a chance to calibrate the exact positioning of the turn so I line up with final properly.
Rate 1 turn is the Standard rate turn, or 2 minutes for a 360 circle. At 60 kts circumference is 2 nm . Diameter of the turn then is .63 nm at 60 kts or about .74 nm at 70kts.
this explains why my rc landings are so rough. Thank you!
Happy it helped!
The arc is what I do and have done for some time. If you want you can fly a bit further out for better visibility.
In Ultralights we're already flying slow and a single sweeping curve is easier to maintain airspeed and if you overshoot you can just keep your altitude and bank angle until you get over the runway. With 90 degree turn to final if you overshoot you wind up trying too many dangerous adjustments mid-turn leading to the stall spin.
My CFII son-in-law says your pattern is too small if you don't have time between downwind and final to flatten your bank (straighten out) long enough to check outside the turn for traffic that may be trying a straight-in approach. Maintaining DMMS (design minimum maneuvering speed) in the pattern turns will also keep your airspeed high enough to prevent the inside wing from stalling in the turn. Use the final approach to slow to landing speed.
Too wide a pattern risks losing site of the airfield in poor visibility, but of course you can always briefly roll wings level on base to check for traffic flying straight in. Maintaining DMMS is all very well but the point of the video was to indicate how the consequences of errors or distractions in a critical phase of flight could be mitigated by flying a base to final segment within a wider envelope of safety.
Makes sense. Many years since I flew, but it seems that if a pilot could set up for the safest approach well ahead of his/her landing, many of the tight turns could be avoided by a straight-in approach.
There is a lot of writing about why this turn can be so dangerous when people have no trouble making similar turns in the air. To me, the obvious different factor is the ground rollout reference instead of a heading. Now, not only are you rolling out on a particular heading, but you’re additionally tasked with lining up the rollout to make it tangent to the turn. I believe there is a tendency to make a decreasing radius turn when you realize an overshoot is imminent.
This type of large radius turn gives you much more margin to adjust than a discrete 90 deg base to final, and a variation is totally standard for gliders.
Absolutely: as I explain in the video, it is the combination of a precise target (the runway threshold), low airspeed and low height that create the danger.
As you say, glider pilots make curved approaches as do military pilots, so why are private pilots not trained to do the same?
Low altitude turns to target make more sense than turns to heading. We want to go where we want to go, target, and not hit things in the limited horizontal space available. We should also use the vertical space available as potential energy of altitude traded for airspeed. If we always make turns the way the airplane was designed for safety, Wolfgang asks us what the airplane wants to do, we would relax the back pressure and make 1 g turns at whatever bank angle is necessary to acquire the target. We do this with every turn crop dusting. The target is the crop or in this base to final instance, the target is the numbers. I understand the large traffic pattern now days at big airports, but we don't need to stay up there. Also, if we bank more than we think we need, while releasing back pressure, early in the turn, we can decrease bank when coming around onto target so as to not have to increase bank late in the turn when lower. The design of the airplane, dynamic neutral stability, is to fly. The design prevents stall unless a pilot pulls back on the stick. The other issue would be wind management. If practable, make this downwind to final turn into a headwind component any time the wind is crosswind to the runway.@@pretavol
@@pretavolThis might interest you - in Australia, glider pilots are taught to always make 'well banked' turns in the circuit, and generally this includes discrete turns onto base and final.
I believe this is to reduce the temptation to 'over-rudder' the turn, which might occur in a shallow bank which is overshooting the runway. It sort of makes sense, as glider pilots are used to using lots of rudder in basically every turn - it's easy to see how someone could reflexively use this to drag the nose around while turning into final.
Of course, glider pilots are also taught to modify this part of the circuit in any number of ways in order to deconflict with traffic and ensure they stay on the right glideslope.
Really interesting video. Just to add my 2 pence to the age old question/debate. I learned to fly in the 80s when in the RAF and my old WW2 instructor used to call the square circuit, the bomber circuit and the curved approach the fighter approach, being a former Hurricane pilot and 707 pilot he thankfully taught me both. I also had many a flight in modern fast jet fighters and saw the same curved approach. The history I was told goes back to WW1 and WW2 bombers needing more space and a more “procedural” circuit where fighters needed the curved approach to see over the long nose, it took less time making them less vulnerable to attack. Jump forward to modern airliners and a 1000 foot square circuit makes sense as it allows time and can be more procedural and for the airline trainee route has become “standard”.
I teach and examine the square “standard” circuit but am a big advocate of a 800 foot circuit and curved approach if taught properly. Many aren’t taught properly; and I’ve seen pilots loosing a dangerous amount of speed on the downwind to base turn by closing the throttle too much, and over banking at the same time while delaying the descent, along with the loss of lookout under the up wing on base to final turn in low wing aircraft. There’s a reason it’s called the dead side. It is more intuitive than procedural.
The square circuit is an easier method to teach and learn as power is only removed for the descent on base after the turn, a descent is then started and trimmed stable with or without flaps before the turn to final (less to do and their is time to do it). My opinion is for students, novice, less intuitive pilots and those destined for a modern passanger bomber the square approach provides a better (safer) option.
Sorry for the long answer but it’s an age old question.
Thanks for your comment and I agree that the key word here is "properly". Executed properly, with a constant bank angle, constant airspeed and constant rate of descent, I feel that a curved approach with good lookout has to be safer than performing a sharp base to final turn at low height, particularly for the inexperienced pilot. As you say, it's an.age old question and I expect the debate will continue!
Even worse if a crosswind is a tailwind on base.
At broadside to the end of runway always pitch down add flaps until base leg. No stall if pitching a negative angle of attack.
My point was that the risk arises at the base to final turn, not broadside to the runway on base leg. The aircraft will stall even at a pitch down angle if the critical angle of attack is reached!
Ex Navy pilot here.... Agree 💯
Being ex military, I fly a long gentle curved turn... but think its what works safely for you...
This thread is a good discussion and a nice video explanation. I do both approaches. For very short (and I mean very) short finals I do the rounded approach, for all others I do the squared approach because I have a low wing and want to be able to keep track of traffic. I really do not think the squared approach is more dangerous than the rounded approach, provided that you know and respect the aero dynamics. Dangerous situations arise when pilots are not aware of these, no matter rounded or squared approach. A squared approach looks squared on paper, but you do no turn on a dime with a 30 degree turn. Thus I use at most 30 degree coordinated bank angle. This increases stall speed by a approx 7% - I always keep the airspeed minimum 30% higher than the stall speed at the current flap setting. I use the height loss in turns as a normal descent. If I misjudge the height loss I add power, I do NEVER pull back on the stick (remember pitch change = speed change, throttle change = height change). If I overshoot and cannot make a coordinated turn by a large margin it is a go around. The overshoot situation is the setup for a skid turn to align up with the runway, with brings you in close danger for an unrecoverable spin.
Most importantly and even though I have been flying for 23 years I still twice a year train landings. Typically 12-15 landings in 2 hours. High approaches, low approaches, long/short, with flaps, without flaps, rounded approaches, squared approaches, forward slips. Totally MANDATORY is correct airspeed at all times, correct descent, no bank angle > 30 degrees, always coordinated, never pull back on stick, never overshoot (go around), spot landings -0 meters/+25 meters. The result is that a non spot landing are rare. I do this because I am a firm believer of always doing the same landing is the most dangerous you can do. Different runways, sloped or not, obstacles, traffic you are not used to, weather conditions etc. dictates that you can not always perform the same kind of landing. And when you are trying to do a "landing pattern" you are not familiar with you introduces a stress factor which for some pilots result in unintended bad decision making during landing.
Thank you for your comment. I certainly agree that practicing landings under different circumstances is a good thing, keeping to a discipline is the way to avoid errors and different circumstances may require different methodology. The point that I was trying to make in the video, however, was that a high workload due to distractions such as weather, traffic and so on can break that discipline, lead to errors and, potentially, loss of control of the aircraft. Maximising the safety margin reduces the risk and gives more room for recovery in case of need. I think that making a continuous curved approach, where the aircraft will hold the chosen angle of bank without additional control inputs, does reduce workload and generally increases the margin of safety.
I very much agree that a square pattern is dangerous. However, a constant-bank 180 from downwind to final makes it very difficult to 1) scan the final approach for aircraft making long, straight-in finals, and 2) makes it much more difficult to compensate for strong [cross] winds and, particularly, winds that change significantly between pattern altitude and the surface. After all, it is those winds blowing the unsuspecting pilots towards the field that is the primary root cause of base to final overshoot.
My preference is to dog-leg the base/final, i.e., a normal 90 degree downwind to base, then wings level for a good scan for those straight-in finals, and *then* turn towards a point a few hundred feet from the threshold for a very short final.
In a high wing aircraft it should be easier to spot traffic on straight-in approaches throughout the 180° turn compared to a rectangular approach. For a low wing aircraft it will be easier for most of the first 90° and more difficult (even though the bank angle is modest) for the next 90°, but collisions in the circuit are relatively rare compared to crashes due to base to final stalls.
As far as the wind goes, I find it easier to make gentle compensations in a long turn than try to do it all at once in a tight turn. If I get it wrong on a curved approach then I can go around, but getting it wrong at base to final can be fatal!
When I learnt to fly, I was taught to square-off the corners and as I currently fly a flexwing where the stall-spin is not such an issue, it's a safe procedure. However, over the last couple of years I've changed to the constant curve from downwind to final as I find it much easier to line up onto the centre-line.
From what I can see, in a high-wing aircraft the constant curve still gives you good visibility to see anything else on final, but for a low-wing aircraft the squared-off circuit could be required to ensure a clear view on base before turning final.
The other issue is that if you extend the downwind leg or move it further out, you risk not being able to glide to the runway if the donkey dies. Again, that was another thing drummed into me in training. If I remember correctly, glider pilots refer to it as the 45° rule.
Thanks for your comment. I agree that with a curved approach downwind to final in a low wing aircraft the view of other aeroplanes on a straight-in approach will be impaired for at least the second 90° of the turn although I think it could be improved for the first 90° because the other traffic will be more towards the centre of the circuit traffic pilot's line of sight, but the method can be modified to do a tighter turn downwind to base and and still curve the base to final turn. The point I am trying to make is to keep the maximum margin of safety in that last turn where the risk is highest and distractions can cause mistakes and misjudgements with little room to correct.
@@pretavol Hi, thanks for your reply and all fully understood.
Yes, that final turn is the most dangerous especially if you've left it a little late or misjudged the crosswind. Probably best to go around rather than overcook the turn and come to grief, but in the heat of the moment it's no wonder it's a very common mistake..
regardless of method, I always teach my students to start the turn to final early if they aren't sure. as they can always adjust mid turn and shallow out the turn to hit the final course alignment. better that than steeping the turn. turning early gives a larger radius and shallower bank overall.
I use every type of method myself, depending upon the situation.
The base to final turn is supposed to be a descending turn, so the increases in stall speed are only really relevant in level flight, or climbs. Increased g-loading is required to increase the stall speed: if you don't apply back-pressure, you won't stall (in general).The risk comes when a pilot allows themselves to be too low on base, then overshoots and tries to overbank without losing height. At that point, it's best to go around and try again.
I like the constant turn method, but I suppose the benefit of the rectangular pattern is a slightly longer final approach leg for configuring and assessing stability. There's more than one way to skin a cat :)
Yes, it is SUPPOSED to be a descending turn but, as I was trying to indicate in the video, the problem arises when the pilot is distracted (by traffic, radio calls, weather etc), becomes overloaded, makes an error, overcorrects on the flight controls, or lets the airspeed decay. Flying a gentle curve base to final gives a wider envelope of safety in which errors are less critical and the pilot has more opportunity to make corrections safely.
I keep repeating to myself "Airspeed is King" and push the nose down more during the downwind to base and base to final turns to never load the wings.
True, but the problem arises where the pilot is distracted by something (radio, traffic, weather). If the pilot is in a situation that gives a greater safety margin, ie a gentle banked turn, then there is a better chance to salvage the situation.
THANK YOU!!! I've been jabbed by my wife ( a better technical pilot) for doing this for years. I feel vindicated!
Hi Captain, I put an additional point in the situation: if the pilot let the airplane naturally descend in the turns (not pull the stick), the stall speed will NOT increase. And considering the goal is to descend and align, this is the way to go. Is that correct?
In a turn, ailerons and elevator are used together to maintain the required turn rate, but the elevator also has to control the sink. How much rudder is needed depends on the adverse yaw characteristics of the aircraft. It's all a matter of balance. If everything is perfectly stabilised then you are right, but a wing can stall even in descent if the angle of attack is high enough, so if the turn is too tight, and the inside wing becomes too slow, it can still stall. The point of a curved base to final turn is to keep the aircraft in a 'comfort zone' where, even if the pilot is distracted, there is still sufficient safety margin.
I've lost several planes in my time from this exact mistake. Fortunately they were R/C aircraft so no fatalities, but pretty damned expensive. I'm not the only one by far, and for awhile we all thought there was a signal dropout zone in one notorious section of our flying field - but we eventually figured out that we were banking way too tight in order to line up with the runway. It can be pretty difficult to guage these things when you're standing across the airfield from your plane with your transmitter, trying to control a model plane that is quickly banking towards you at an angle. Cost of an education as they say.
R/C aircraft are an order of magnitude harder to fly than full size aircraft. Although it is utterly unprovable, I would bet that pilots that started flying models before moving on to full scale are at half the risk of dying as other pilots. Although, last time I was at a model airfield half of the aircraft had wing levelers and gyros, maybe that cuts back on the most important lesson of fly the aircraft all the way to the crash!
Interestingly I exclusively fly with gyros in nearly all my models (using a setting that fights off singular interference to the intended flight path, the models don’t auto level).
Despite the additional support this turn is indeed still the hardest of the four corners, which I hadn’t fully realised I was aware of until watching students make the same mistakes as you described, sometimes ending in disaster and always followed by bewilderment.
-a model aircraft instructor
I feel you...I've lost three wives like that.
Don't worry, I'm OK. They were all trying to skin me alive in divorce court anyway.
.......Also lost my mailman and a neighbor that way
Glider pilots cut off the corner for similar reasons to avoid running out of speed and height in the wrong place.
I'm a glider pilot and this is indeed a dangerous (most dangerous?) part of flying. However at busy airfields our circuits tend to be pretty boxy for predictability and visibility. A longer downwind can be dangerous on windy days. That's said I'm basically for this method, although a 45 degree bank is de rigeur in a glider, in the high workload scenario of lining up for final, it's easier to make a mistake and let the airspeed slip.
Very good video. The other reason this constant turn from downwind to final is good is that the bank angle required is low which allows for better visibility to watch for traffic. No matter how I maneuver in the pattern, I never stray from calculated minimum speeds and maximum bank angles for various landing configurations, giving healthy margins above the stall.
You brought in a very good point, I thought of that when I was learning 20y ago, It did not make sense to me at that time, but I didn't feel questioning my instructor..
Exactly!
I strongly prefer the squared approach because I can not see the runway while making one large turn. In a Cessna 150, the wing blocks my view.
When I first adopted the method I picked a reference point on the extended centre line. That would be visible throughout a downwind to final or base to final turn in a high wing aircraft.
i always turn sooner with a shallow turn from base to final for l find it safer.
Smooth curves in so many walks of life is always better than sharp angles. A curve spreads load and stress and in this analogy slows the process down giving more time for adjustments. WW2 fighters always used a wide smooth curve to threshold, tho admittedly that was more to do with visibility over a long nose.
Steve what software did you use to explain, keeping variables constant early insures an even movement of the plane, therefore allowing for early extrapolation
Sorry, I am not sure that I understand. Do you mean what software did I Use to produce the animations?
@@pretavol exactly
I generated all of the animations in Apple Keynote,
I fly like I was taught in Naval Flight Training. Race track pattern and not the Air Force box pattern.
Simple and elegant. Try it.
Are the values you provided applicable for most planes
The graph of percentage stall speed v angle of bank and the percentages in the next clip should be applicable to any aircraft...Each aircraft will, however, have different stall speeds and it is vital that the pilot is fully conversant with the aircraft's performance before considering any manoeuvre. Some aircraft are designed to be much more forgiving and capable at lower speeds than others.
What isn’t consistently taught to students, and rarely brought up on check-rides is the very simple idea that there is no hurry to land, once in the pattern. Too many pilots think they MUST do tight patterns, tight turns and execute expedited arrivals. Wrong, and some cases fatally wrong. I have taught, as a CFII, to give yourself timed VFR patterns. The timing depends on type of aircraft, weather and or wind conditions and workload. The first timing comes as you either enter your 45 to downwind, or fly the crosswind. Instructing, I want to see no less than 5 seconds between the aircraft and distance to runway. In other words, if you were to approach the runway perpendicular, from downwind to centerline would take 5 seconds. At an average airspeed of 80, this puts you no less than 200 yards out on downwind. On downwind and once abeam the numbers, I teach the minimum 30 second rule. 30 seconds of flying downwind past the runway before the base, base to final turn is made. No bank angles greater than 25 degrees. Airspeed no less than 1.2 stall at ANY phase of the pattern. New and old students alike, it’s a must for a timer on the yoke and a notation on airspeed indicator ( or predefined alert on the flat screen tape ) for 1.2 stall given predetermined density altitude.
And of course … communicate, communicate.
Some airfield don't like you flying the military style circuit. I like than as you only make two turns instead of four to fly a circuit.
I'm not convinced that well-banked final turns are more dangerous. I fly gliders, and what generally kills pilots is slow, under-banked, over-ruddered turns resulting in a stall/spin too low to recover. Yes, the stall speed increases with bank angle but then the nose tends to drop keeping the speed up and making it much harder to stall with the available elevator authority or by over-ruddering. But perhaps it's different with powered aircraft.
Yes, I appreciate the phrase “well banked”. The point of the video was to try and highlight how a danger might be mitigated by giving the pilot a wider envelope of safety at a phase of flight where margins for error are narrow (low and slow and in a turn) and distractions (such as weather, radio calls, other traffic) or misjudgements (such as of a tailwind on base leg) can result in disastrous mistakes.
In My training days, I liked the idea of a more continuous down wind-base - final turn. But levelling off briefly to check the pattern for traffic for untowered airports makes a hell of a lot of sense. High wing vs long wing situations potentially arise if you don't level off for a few seconds to look around the pattern
Called it the (american) football pattern. Looks a bit oblong and unsmooth on radar
Whilst the pilot will have identified other traffic whilst on the downwind, I agree that, as I intimated in the description, the remaining pattern may have to be adjusted according to circumstances.
It may be depicted as a right angle turn but it should be a rate 1 turn also. If you crank it over to do a tight turn the yes, these factors are working against you, but every turn at low altitude and low airspeed should be no more than rate one.
Indeed it should! But it often is not, with much greater bank angles being used sometimes. I agree that the turn should be better depicted and described; that was partly the point of the video..
What if you put the nose down during the graveyad turn ?
Doesn’t avoid any chance of stalling.
The point that I was trying to make is that, in the presence of distractions (for example: weather, radio calls, traffic) the pilot may lose concentration and put the aircraft at risk of a stall. Flying within a larger envelope of safety, by making a gentle curved turn base to final, gives the pilot more opportunity to correct errors before it is too late.
Excellent video! I plan to implement this change in my pattern work.
Thank you!