DDD1: Saab 340 -- Design quirks & onboard a very special flight HD 1080p
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- Опубликовано: 21 май 2024
- In this Design Deep Dive we go flying on the National Flying Laboratory Centre's (NFLC) Saab 340B+ (G-NFLB) and we explore some of the interesting design features of this nice little turboprop, from its geometry, payload-range space, competitors, its CT7-9B engines, through its OEI (one engine inoperative) design, to its stall warning and stall prevention system, handling, and much else.
Timecodes
0:00 - Intro
0:30 - G-NFLB approach and landing at Southampton
4:50 - Saab 340 - a history of the type in one minute
5:50 - G-NFLB - a special 340B+
6:53 - Tail quirks
10:22 - An asymmetrical aeroplane
15:46 - 30 Fiestas per side
18:33 - Wings, fuel, payload, range
23:57 - The Class of 1983: the competition
26:31 - Ready for departure
29:09 - Engine start, taxi, and take-off
31:40 - Climb-out
33:41 - Stall protection: speeds, flaps, CLmax
39:19 - Stick pusher demo!
47:51 - More demonstrations: performance and stability
49:03 - BANK ANGLE! BANK ANGLE!
50:21 - Short period pitching oscillation demo
50:50 - Phugoid demo
51:46 - Dutch roll - with and without the yaw damper
53:48 - Conclusions and credits
I am deeply indebted to the NFLC crew for their invaluable support for this project and for being the perfect partners over the years in delivering aeronautics education to many generations of our students.
Professor András Sóbester is an Airbus Chair in Digital Design at the University of Southampton. www.southampton.ac.uk/people/...
Twitter: / asobester 
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Do you fly/have you flown the Saab 340? Did you work on the design? Do you maintain/repair/overhaul it for a living? I'd love to know what you think of the aeroplane and what she is like to live with in your airline ops! Do comment below :)
Would love to fly this machine one day. Heard a lot of good feedback about her.
I fly the plane, pilots love it!
The 340 was my first type rating. Solid little plane, but wow what a complicated electrical system!
Interesting! More so than comparable regional turboprops?
@@asobester more so than the a320 that I fly now! The 340 has so many electrical busses that Saab can't actually decide how many busses there are, depending on the way you define a bus. I want to say its like 26 busses. This component is powered by bus A, but the actuation is powered from bus B. In the event Bus B fails, its logic now reverts into an inverter off of Bus A, and that inverter is powered by Bus D when the flaps are greater than zero.
Thanks, I enjoyed both the Saab and 727 video. Please upload another anytime you are able!
Thanks, will do!
just my fav airplane. Some complain about noisy cabin, but at least you hear what's going on.
I flew that very plane for Mesaba!
Cool! What was it like as an airliner? May I ask what city pairs were you operating?
I got to fly on 402 recently. The first of the last B+ batch for Mesaba. Same grey seats.
I have never flown anything weighing more than 2 tons, but as a 4000 hrs flight instructor with frozen ATPL and an engineering background, I found every bit of this video interesting. And I do envy those students in their flying classroom.
Thank you, I’m very pleased to hear that 😎
What a fantastic video. Cranfield send this beast over to Shannon once a year for the "Flight Dynamics Laboratory" module for the Aeronautical Engineering students from University of Limerick. Looking forward to taking my turn in it
Thank you! And you’ll love it, I’m sure, most of our students do.
Flew a 340B for about four months way back. From what I remember was fun. We pioneered alot of new routes in Europe, as airline was expanding in the 90’s. Very nice time…
I flew her with her Mesaba, great to see she is still flying in such an interesting role.
This is a really well-made and interesting video! I’ve flown the Saab 340 once and flying it again in January with Loganair. Very interesting to see how much thought went into its design!
Thank you for the kind words. Your flight in January will probably be one of Logan’s very last 340 flights, I think they’re retiring them on 20-21 January with some special ‘enthusiasts’ flights out of GLA.
@@asobester you’re welcome. I shared your video on my instagram page to show it to others.
Are you going to be on one? I’m on the 11.30 flight on the 20th.
Lucky you! No, I won’t be able to make it, but this sounds like a very rare opportunity and I’m glad Logan are retiring the SF340 in style!
@@asobester it was a great idea!
If you’re able to, try making some more of these videos on other commercial aircraft. This one was really interesting!
Thanks
@@machaviationofficial Thank you. And your wish is my command! 😎 Next one should be out in late January.
This is a fascinating video! Thank you so much for showing us so much "behind the scenes" info on the Saab 🙂
Glad you enjoyed it!
What a fantastic video. Thanks a lot.
Thank you, Chris!
Thanks for this thorough discussion of the aerodynamic aspects of this very fine small airliner!
I have flown the SF-340 in it's early days with Crossair (if memory serves, we were the launch customer - as testified by some of the prototypes having had Crossair's livery on one side of the fuselage and SAAB's livery on the other..).
These early SAAB's were generally nice to fly - except in icing. First, they lost roughly 30% of engine power when de-icing was switched on, and secondly had a tendency to accrue ice on surfaces not reached by the de-icing systems (had one rather hair rising experience over the Vosges hills on approach to Basel-Mulhouse one late and icy february night..). To my knowledge they did modify these shortcomings after I left Crossair (mid eighties or so). Thanks again for this very interesting footage - much appreciated and very much enjoyed by this retired captain. 👍
Regards from Switzerland Charles U. Schneiter
Thank you for the interesting insights! The hybrid livery must have given ATC some moments of confusion 😉 I was fortunate enough to speak to a Crossair engineer from that time and he had similar recollections re icing. I guess this was a decade before American Eagle 4184, so much less was known in those days about icing than we know now...
@@asobester Oh yes, some confusion there was indeed - even sometimes for us pilots. " Bale Ground, this is SAAB Demonstrator 015... eeehhhh. Crossair 651, sorry..". 🙃Said incident over the Vosges hills started by an ever so subtle change in wind noise... First thing for me: Switch off the autopilot to get a feel for what's happening. I then felt a slight vibration in pitch. After that I started an immediate descent.... lower down (below freezing level) the vibrations stopped and we made an uneventful landing. Wrote the tailplane de-icing systems up after landing. Albeit no problems were found by maintenance and engineering. For me this said, that de de-icing (at least for the tailplane) as such was somewhat inadequate. But besides of this, the SAAB 340 was a delight to fly! Especially after having flown the Fairchild Metroliner II and III for almost 1500 hours (my hearing suffered quite some then.. 😉 ..).
@@charlesschneiter5159 Wow - must have been quite unnerving. I guess the tailplane is even worse, because you cannot Mk1-eyeball what is going on! I know some airlines later painted a black line on the prop spinner, the visual disappearance of which would then serve as an icing early warning system... did the Crossair airframes have anything like that? And, interestingly, you're not the first pilot to immediately mention the Metroliner in a SF340 conversation as a... less than a delight! What in particular did you dislike? (other than the noise) In what way was it different? Fairchild 'DNA' in both, to an extent...?
@@asobester Well the Metro II's and III's were sporty little machines. Handling wise the Metro III was not so pleasant like the Metro II - in that they considerably increased the former's wingspan but let the ailerons where they were i.e. they were then too much inboard. Gave somewhat the same feeling as one gets when driving a car whose power steering is u/s and having too much play in it...
And the systems were quite the opposite to them in the SAAB. Not really thought out well imho (a bit like in some business jets of the time). Oh, and yes, the manufacturing quality of the Metros left a lot to wish for. So, no, they didn't have much in common engineering wise - thank goodness! Imho the cooperation between SAAB and Fairchild was more of a commercial nature than anything else (probably that SAAB thought, that they could enter the US market more easily?)
In fact, yours truly had a veritable accident in a Metro III when the nose wheel steering (electro hydraulic spool valve design) 'froze up' due to metal flakes getting in between the spool and the small piston inside the cylindric wall of the spool valve (the Swiss AAIB found out that the reason was due to an unsuitable selection of materials plus lousy manufacturing of the valves). After touching down, the aircraft veered to the left, we then hit a runway edge light with the nose wheel that caused it to break and we drove nose on ground approx. 200 meters out into the weeds. The airframe had to be written off since the fuselage became substantially twisted and both engines (TPE 731's) were totaled as well as both props smashed into the ground when the nose wheel went. I still have one of the bent prop blades here in the office ;-) .
Sorry for the somewhat lengthy reply!
Kind regards from Basel Switzerland - Charles
@@charlesschneiter5159 Thank you for the fascinating recollections! I have never seen one in flight and I'm now adding this to my bucket list :) So many interesting quirks... (well, maybe the wrong word for badly made valves!). There is an unreferenced statement on the Metro's Wikipedia page about an emergency RATO system being offered as an optional extra. Is this something you ever came across? I hope it's true!! And on a more mundane note, do you recall your pax ever complaining abut not being able to stand up in the cabin? Does it not get a bit claustrophobic after a while? (say, waiting on board for whatever reason?) Apologies for all the questions :)
Amazing insights of this great looking turboprop … looks like a fun plane to fly, loved seeing them around with their tartan livery when I was GLA based 🏴
Thank you - glad you enjoyed it!
Only just came across this video. The Saab 340A was the main type in the first airline I worked for (Business Air). We eventually got three 340Bs in the mid-90s. They were reliable, once you got used to its quirks and pre-winterisation checks on the icing systems helped with serviceability in the early part of the winter season.
Nothing is perfect, but the SF340 is a nice little puddle-jumper. A very interesting video.
Agreed. And I’m glad you found it interesting!
Excellent video about the new Cranfield Saab340B flying laboratory.
Absolutely brilliant video. Thank you, loved every second of it
Awesome, thank you for letting me know!
What a great video, András, and what a wonderful learning environment for those lucky students!
I have no particular knowledge of the Saab 340, just that I’ve ridden in the back of it on several occasions, the last one being LNK-MSP on a dreadful winter day, perhaps in that very aircraft as it was a Mesaba flight. It was noisy in the back but better than many of its peers, and it always got me there safely. As an aside, I did have a friend who flew it for years out of Dallas, and she said that the 340A was hot and underpowered on a summer day in DFW, but that the 340B was a joy to fly. She really liked the plane, though I did get the idea it had some systems quirks that were unusual.
I always like learning new things, and the lack of contra-rotating props, angled nacelles, and the vortex generator arrangement were fascinating. They are frankly never things I would have thought of with zero time in multiengine propeller driven aircraft.
I did have a couple of random thoughts as I watched the video. I too had always noted the very pronounced dihedral of the horizontal stabilizer, but didn’t understand its aerodynamic significance; in addition to the Viscount, I’d also point out that the Comet and the DC-10 have very pronounced dihedral of the horizontal stabilizer, and if you have a general explanation for why they needed it compared to other similar aircraft that might make an interesting video.
Your payload/range discussion was a very good introduction, and is something few outside the field grasp. I would point out that requiring a distant alternate can have dramatic real world effects on the number of passengers you can carry (the CRJ200 is terrible for this). I lived in Minneapolis for years and the winters are grisly there; large snow events can extend hundreds of miles meaning you may have very distant alternate fuel requirements making passenger ops economically unviable.
I enjoyed the briefing and approach to stall/stick pusher demo in the video, and I’m sure the students will remember it well. I have flown aircraft with and without stick pushers; generally the T-tail jets are the biggest concern (I think the first stick pusher was on the Trident, but I could be wrong). The DC-9 and B-727 didn’t have stick pushers (at least the ones I flew didn’t), but the MD-80 did and it was extremely aggressive: it would take the yoke right out of your hand and essentially slam it to the forward stop; the 340 appears somewhat tamer, though I’m guessing power on stalls in the Saab would be very adventurous with the props turning in the same direction!
Anyway, thank you for teaching me some things; this was wonderful!
Thank you so much for the kind comments! So thrilled that I was able to tell you a little that was new.
The business of distant alternates is one of those that engineers rarely think of, but it certainly is an interesting aspect of conceptual design. I’m particularly fascinated by pairs where the departure airport is also the alternate for some aircraft (SEA-ANC? HNL? Antarctic ops?)... I should have mentioned this in the context of the range of the 340 as well, which is seemingly underutilised in pax ops (I guess these also explain the need for oddities like the long range tank mod on the DHC-8 - I used to wonder who fancied 8 hours on the Dash, but actually I guess it is to unlock remote destinations with distant alternates and/or no ground services).
Re power - the improved performance of the B model is actually good news for us too here in SOU for these 'flying classroom' ops the awesome Cranfield NFLC operate for us - on a hot summer’s day the rising terrain to the South of the field (ancient woodland with tall trees) can be payload limiting on some twin turboprops because of the EFATO constraint... (their previous platform was the JS31, which was lovely, but problematic in this sense).
I had an offer to study Aerospace Engineering at Southampton in 2004... a poor open day experience prompted me to go to Bath instead. In hindsight maybe I'd have done better at Southampton!
Beautiful video, brought back some good memories from G-NFLA too!
Thank you! I must make a video about NFLA too - I too have a soft spot for the Jetstream!
I flew the SAAB 2008-2011...Very systems intensive, but very easy and forgiving to fly...It was a bit underpowered, but pretty benign single-engine, assuming the autocoursen worked:-)
Does 'systems intensive' mean 'overly complex' or 'over-engineered' relative to what you'd expect from an aeroplane of this class/vintage?
@@asobester I'd say for it's era and it's mission that it was a very complex airplane...However, it was simple top operate once you got accustomed to it. I had come from the Beech 1900 prior to the SAAB. I really enjoyed the roomier cockpit and autopilot:-)
SAAB 340 is multi-engine, not a single engine.
@@m.hstudioproductions6642 I know, I have almost 2000-hours in the SAAB 340. I was referring to it's OEI ( one engine INOPERATIVE ) flying characteristics...
@@B1900pilot Ohh, I see.
Was a Capt on the S340A in the late '80s for a regional in the southern US. Since then have flown nearly three decades with a major US carrier including the B727, B757, A320, and A330 which I fly now. I still have fond memories of six or eight legs a day in the reliable and comfortable Saab. I particularly liked the roomy cockpit and cabin, but also remember the engines (derived from helicopters application) were not the best performers in the high teens flight levels, nor in icing conditions. Beautiful design that looks great today, and flew very much like a B757 in terms of feel. Thanks for the trip down memory lane!
Thank you for sharing your recollections! And yes, all conversations about the 340 (and I guess about most turboprops) eventually touch on icing, including engine inlet icing... And you're right, its lines still look modern today, even in an era of curved windshields, etc.
Did you get to do any similar exercises in the course of training - stick pusher demo, dynamic stability, Dutch roll etc?
Probably, but it has been over 30yrs and I can't remember what I had for breakfast this morning 😂@@RoamingAdhocrat
A highly enjoyable and informative video! I particularly liked the 'Fiestas' segment.
Thank you 🚙🚙🚙😎
Thanks Andras for such a informative movie, I found it very helpful. As you said, this achievement was not possible without the help of Cranfield university team. I have recently participating in this class at NFLC as a educator and I would encourage every university to take part in such training class. A gentle feedback, that turbo prop is the least efficient airplane in term of fuel consumption, noise and yaw stability, hence we have seen low CL (1.9) at 6-8 Reynold number. But, anyway, it is a learning curve for the students.
Fantastic - thank you!
I loved flying it 28 years ago, have a little over 5000 hours PIC in it.
Just could never figure out why Saab designed the hydraulic system the way they did….definitely an Achilles Heel… 8:40
Can you elaborate on what you didn’t like about the design of the hydraulic system?
@@asobester If I remember correctly, the Saab has a closed loop hydraulic system. Having a leak could be catastrophic. Other than accumulators there isn’t a another system. Other aircraft such as the Bombardier CRJ, Airbus A220, A350 all have multiple separate systems. Also, the Saab has 1 electric pump ( no engine driven pumps), I believe a hand pump as well. Should that pump fail the crew is worked extensively.
It seemed to me that after designing the aircraft they forgot to incorporate a hydraulic system and scrambled to do so.
However, I and many others who flew the Saab enjoyed it. It handled like a C172…Prior to my days of the Saab flying I flew a Jetstream 3100….so the Saab was a welcoming treat.
Perhaps their thinking was that in case of complete hydraulic system failure you can still gravity-extend the landing gear, so the worst case scenario is a flapless landing with no brakes? Not ideal, but at least you still retain all primary flight controls, come what may?
@@asobester true, however I believe the up locks were hydraulically actuated and if all hydraulic fluid was lost and or the emergency accumulator drained the issue would be the up locks not releasing. It’s been quite some time since I flew the Saab (28 years)and could be forgetting some system’s knowledge, but I flew it for 6 years as a Captain, line check airman and simulator instructor. One of the memory items with such a catastrophic failure at the airline I worked for at the time was to turn the electric hydraulic pump off, slow aircraft, lower gear before all pressure was lost. Yes, the use of brakes, anti skid, flaps and nose wheel steering was lost, but was a small price to pay (I agree with you) for just having gear down and locked.
Ah that makes sense, I suppose most failure modes, if detected early enough, would leave you enough time/hydraulic pressure to lower the gear before you lose all the fluid/pressure…
it looked better in Northwest Livery. Quite a few here in Australia. I read somewhere that Rex Airlines is looking at retrofitting the power source....
I think when they originally designed it, SAAB wanted to put a PW 120-series engine on it...
brilliant stuff. I love flying my LES Saab in Xplane :)
thanks so much for this
Thanks - glad you liked it!
I hope they update it for XP12...
Ok I want to enroll in this class just for the ride.
Very nice video, but if you could be behind the camera and use some pointer while explaining the exterior details. Liked this video very much, thank you.
Thank you, and noted
GE CT7 power 😍
26:25 is that from Ron Rogers?
Can you do a video about the Fokker 50?
I shall put it on my to-do list!
@@asobester thanks very much. I appreciate that. I look forward to seeing it. The aircraft is as intriguing as the Saab 340.
Nice Video....anyone else find the audio volume terribly low?
Andras, absolutely facinating! We take all this for granted but it is good to see what goes on behind the scenes of certification. Would be wonderful, as a PPL, to see you one day do a deep dive on a typical training aircraft like our ancient Piper Cherokee PA 28-140. ruclips.net/video/ZvlxJ1oLCb4/видео.html
Thank you, Anthony, I’m glad you found it interesting! I share your fondness of ancient trainers - here’s my deep dive on one: ruclips.net/video/NzOFVv8747Y/видео.html
@@asobester Great! I will have a look!
i i i ilike planes👍
I remember doing a jumpseat ride in about 1995ish or so from Nice to Stuttgart and back. I flew a KingAir B200 at the time with the same Collins avionics. I thought that the Saab was quite a bit underpowered, Crew told me about the driftdown and SE ceiling (remember that flight was across the northern Italian/Swiss alps), which I found quite underwhelming compared to the 'mighty' KingAir...but it was a nice ride, noise level were okay etc.
Great insights, it is a shame that the features you talk about were very hard to watch as yor face covered 3/4 of the screen in every shot
Thank you for the feedback :)
Watching your channel is really boring 😢