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(Video) Boeing 717 Stall during test flight

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Amazing video of a recovery after an unusual attitude during a stall test. (vimeo.com) עוד...

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BaronG58
BaronG58 4
My back end puckered just watching this, )
ICMI
ICMI 6
Underwear Check!!!!
captinUradnik
Alexander Uradnik 1
sparkie624
sparkie624 3
Wow... That is quite radical... I expected a good stall but WOW! Not something you want to do on a regular basis...
bbabis
bbabis 1
Agreed! It looked like they had it fully cross controlled so it was going to go around pretty good when it broke.
tol3458
Tom LeCompte 4
Nearly 10,000' of altitude lost. Whew!!
bbabis
bbabis 8
The only thing that saved them was starting it at 15,000. To level the wings inverted and pull through was very close to being dead wrong. Push and roll level is what was called for unless they intended to test the dive characteristics of the aircraft.
Highflyer1950
Highflyer1950 1
Normally, I think so, but with the nose pointed straight down and inverted there is nothing to roll towards so at least some pull is required in order to get to the horizon. Although I can't answer if more "g" is placed on the airframe from straight pulling or pulling with bank on? Been inverted intentionally with crossed controls and a very quick flick, but not in a transport aircraft.
sparkie624
sparkie624 2
Either way... It would definitely not included in the class of normal operations.
A6SEA
Bill Butler 1
"Rolling G" limits are normally less than horizontal pulls. I think it's more the stress on the wing(s) than the fuselage.
bentwing60
bentwing60 1
G limits are not bank related, they are config. related. "Load factors" are bank related. For transport category aircraft the G limits are usually around plus 3 to 3.5 clean wing, 2 or less flaps config., and minus 1. Full scale deflection on the ailerons and a modest bank, with no rudder, will do that every time at the full stall. Only he didn't seem to know that. I don't care what the guy said in the comments section below the video, if these were Boeing or MD test pilots, I'll kiss your grits. And there is a reason we don't deep stall Transport category airplanes, especially with T tails. Cheers.
A6SEA
Bill Butler 1
Thanks for the clarification. I went deep into the procedures vault for that memory!
bentwing60
bentwing60 1
My apology Bill for a discourteous and overly zealous parsing of your earlier post. Again, apologies.
IanHollingsworth
Ian Hollingsworth 1
Bill is mostly correct. A rolling pullout puts an asymmetric stress on the wings that can make damage more likely. I have never seen rolling g limits specified. They are just plain unacceptable in non-aerobatic aircraft. As to load factors, those are g factors. The issue is not specifically "bank" but is g loading in a turn or pullup. A level flight turn has a direct relationship between bank and g loading. I personally have flown to over 80 degrees of bank in a CASA 212 without putting even 2 g's on the aircraft. That was done in a descending nose low bank.
bentwing60
bentwing60 1
G's and load factor are not the same thing. If the weight or speed limitations are exceeded the load factor may damage or break the airplane even though the G limit has not been exceeded.
djames225
djames225 1
Load factor units are often referred to as G...remember G is not always a positive number and there are Limit Load Factors
bentwing60
bentwing60 1
Review the comment by Bill Butler, above, to which Ian replies "Bill is mostly correct". About what? There are no "rolling G limits", there are only published G limits. And the stress is always on the wings and empennage. A given in the industry, though "I think" in his post indicates a tad of uncertainty that would not exist with a demonstrable amount of tenure in said industry. Ever seen the results of the tail comin off a V tail Bonanza? My original comment simply disagreed and quoted typical G limits and config. factors for transport category airplanes, which I happen to fly. I think the minus G part was in there. Max G X max. gross weight = limit load factor. That's a certification basis. Typically 1.5 times that = ultimate load factor. That would be when the tail comes off the Bonanza. It's all about the weight, and since said MD 717 was doin a test flight, it was most certainly light and probably with a favorable G.G., so whatever the thoughts about how they got there, in the recovery process they may have over G'd it, but they certainly didn't over "load factor" it! As for Ian's "They are just plain unacceptable in non-aerobatic aircraft" I presume he means Gs in roll, how would you turn without them. Cheers.
b4jones2
b4jones2 1
Rolling G's do in fact put more stress on the aircraft. Most military aircraft (fighters) have rolling, or "asymmetric" G limits that are lower than "symmetric" limits. If you're pulling 9 G's, and rolling left, then the right wing is pulling more than 9 G's. Unload, roll, then pull. Ask any fighter pilot.
bentwing60
bentwing60 1
Point taken! I challenge you to produce evidence of any rolling G limits for part 23 or part 25 certificated airplanes. The context of this discussion. It would be published in the limitations section of the POH, and outside the comprehension of the average private pilot. As for the rarefied air of fighter or test pilots, never flown with the latter, but ample opportunities to fly with the former left me with the attitude that I'd rather not. Or ask them a question. Robin Olds ain't the average USAF pilot. Freight pilots have, of necessity, a less superior attitude and a relatively strong sense of self preservation. It ain't about me dissin them, it's about spending a few decades boppin around in old transport category airplanes and doin what it takes to stay alive. So far,so good. And if the right wing of my CL60 ever pulls 9 G's you will certainly see it squawked here.
b4jones2
b4jones2 3
I hear ya, Bentwing. I doubt it's a factor in part 23 or 25 certified aircraft, but from a physics point of view, rolling G's are worse than symmetric G's. That's my only point. My only experience with it is form the T-6 texan 2, everything else I've flown has the same G-limits as your CL-60. However, I will say that all fighter pilots don't share that "better than thou" attitude, I have some good friends from that community who are great at answering questions without pissing you off. Safe flying!
djames225
djames225 0
To me it looks like it was deliberate to see how she would react
bbabis
bbabis 2
Maybe, but 15,000 seams awfully low to start that test unless you already know what it will do.
CHBHA
CB HARDY 0
15000 seems held together rather well on that flight.
djames225
djames225 0
An early test flight, back then, may not have had clearance past 15,000...I know I wouldn't have attempted it that low so kudos to those 3.
bentwing60
bentwing60 1
Back then was 1998 for the test flying or 99 which was the introduction to service for the airplane. Been test flying jets since the mid 80's and as long as you file for and stay out of ATC's hair they will let you do what you need to do, including going to 45'000 feet. It's called "test or certification flight" in the remarks section of the flight plan. I don't really need to see your logbook. And I have already garnered the most down votes for my first comment. Not. It was about the fine piece of airmanship, not the airplane.
Highflyer1950
Highflyer1950 2
Very good teaching tool.
BuddyCox
BuddyCox 2
The pilots looked like they were getting a checkride. Demonstrating the Initial Buffet type maneuver was probably the plan. The recovery would have been to unload the G by using bank and power until the nose fell below the horizon then roll wings level and recover. The horizontal stabilizer is on top of the tail and is out of the broken air cause by the impending stall thus no aerodynic warning of the stall. They had no idea the plane was going to roll inverted. Boeing would never have let them intentionally over stress the airplane like they did. At 10,000', they would have died. There is reason stalls in the type are prohibited and we just saw the reason.
mmann63
maria mann 2
I have questions!!!

That roll plus being upside down happened incredibly quick from the stall. It looks like a huge aircraft and I would have thought maybe it would have happened a little slower. What a panic— for us watching!

So what I am seeing is the 2 pilots "righting" that aircraft from upside down and nose diving? Yes?

At what speed were they going while diving?

And had that aircraft been full of people and luggage would have the recovery been the same?

I wish there was a diagram showing exactly the formation of the plane from beginning to end so I can i understand the exact position of the plane during the stall and then correction procedure. Did they ended up flying in the same direction after the correction or did things get all twisted about? I realize they would be lower but curious as to what happens to the direction of the plane during the correction phase...Sorry for being a so naive on these issues but I am fascinated by it all and very impressed with the pilots who "fixed" this dilemma!


My mother was a pilot. She had a 1968 Beechcraft Bonanza and did all sorts of aerobatics. She was incredible. I was her trusty co-pilot (at the tender age of 5!)
jdriskell
James Driskell 3
I prefer to do this in a Citabria.
bbabis
bbabis 2
Citabria spelled backwards is airbatic. 717 spelled backwards is still 717.
yatesd
yatesd 4
Fine piece of airmanship and a tip of the hat to the 717.
bentwing60
bentwing60 -5
bartmiller
bartmiller 1
This looks an awful lot like a simulator run instead of an actual flight. The inset video with the illustration of the aircraft attitude seemed to be a strange artifact in a real aircraft.

Still, crazy to cross-control stall an airliner. And, as many of you have noted, pretty sketchy to do it from 15,000'.

So, maybe a sim run?
BuddyCox
BuddyCox 1
It could be. The quality of the video is too poor to tell.
bbabis
bbabis 1
You don't get the sun shadows in a sim.
sparkie624
sparkie624 1
That video was pulled from the FDR download and then animated. Note a lot of FAA reports are going to that now days. That was what I thought at first, but I believe that this was real.
paul8626
Paul Smith 1
A nice E ticket ride at Disneyland!
1goodfedguy
Charles Crary 1
I'm amazed at the experience level of all of your comments...WOWSER..you guys are something else!
pwpereira
Pete Pereira 1
There is a brief background about this flight here: https://avgeekery.com/time-boeing-717-went-inverted-testing/
CHBHA
CB HARDY 1
What a rush!
tom101
Tom Campione 1
You bet! Notice the radio operator at the very end of the video. Looks like he was headed to the head....
PBADC3
PBADC3 1
One of the things I noticed transitioning from a C172 to a PA32RT-300T is that the T-tail takes longer to recover from a stall. I could recover in 300 ft. from a stall in the 172 but I'm lucky to do it in 600 in the Lance. Of course, it might not be due to the T-tail, just my guess (maybe I've just gotten old & rusty).
MIKESWICK
MIKE SWICK 1
Long time ago I used to crew a Boeing 717 - original Boeing number for a KC-135A funny how they moved the mds to a McDOnnel Douglas bird
mariescreations
Jerry Rader 1
Boeing 717 or 707?
ggraysonlv
GLENN GRAYSON 1
Now we know why pilots wear Five Point restraints or whatever they're called instead of lap seat belts
djames225
djames225 1
Nice find Daniel..
vector4traffic
vector4traffic 1
I'm curious, why would the aural warning say "Altitude" rather than "Sink Rate"?
bentwing60
bentwing60 2
Because the altitude alerter kicked in and the TAWS/EGPWS had not reached its alert threshold. And what Bill said plus some.
Viperguy46
Jesse Carroll 1
Button hole check!
vcollazo
Vicente Collazo 1
NWA was supposed to be the launch customer for the MD95, but after flirting with bankruptcy in 1990 as a result of the hostile leveraged buy out orchestrated by Al Chechi and Gary Wilson we had to cancel the order for well over a hundred of the model. As an aside, since we weren't going to get new aircraft of that size, the decision was made to totally redesign the interiors and hush kit our DC-9 30s, 40s, and 50s. The FAA ruled that the aircraft had to be recertified after the extensive mods which required that each aircraft undergo an extensive flight test as it came out of one the 3 refurbishment centers. The company selected a small and highly experienced group of captains to do the flight tests. I had the good fortune to fly with one of the captains, Tony Gray, and he told me some interesting stories. The airplanes had to be flown into a full accelerated stall which took a good deal of altitude to recover from. On 2 occasions the aircraft went into a fully developed spin so the pilots decided to do no more of these stalls until they talked to the McDonald Douglas test pilots. They were told that in order to avoid future spins they needed to use a type of sensitive instrument that ensured that the acft was totally coordinated going into the stall entry. The company got hold of a couple of these units, and they did not get into any more spins. Tony said that due to the wing sweep and T tail it was most definitely not a gentle nose drop type of stall, but more akin to a fighter jet departure.
NickFlightX
NickFlightX 1
I do believe it was a 717 or MD-90 or similar aicraft, not 727
dbaker
dbaker 1
Yes, a 717 -- good catch. Fixed.
Wingrat
Wingrat 1
Chilling and quickly resolved. Does pilot training in a simulator cover this kind of unexpected reaction to purposeful action. Passengers that think seat belt are for decoration should appreciate the training.
fedexman2
Eric Schmaltz 1
Stay calm and cool and fly the plane. Too bad these guys weren't flying Air France 447.
falconpeter
Peter Andersen 1
Normally I never comment bad or good when flying technique ends in tragedy. This didn't but certainly could have. Notice that the FP rolled the wings level when inverted? The only thing that kept the roll going was momentum induced from the stall. It also looks more like a demo flight than a 'test' flight. Test pilots do not pat themselves on the back until they are on the ground. This was a stall demo that went wrong as the flying pilot did not have the skills to control the aircraft and effectively recover. The pilot flying is likely a management pilot for an airline with an MD or Boeing pilot by his side. The real award goes to the factory pilot in the right seat for not screaming "WTF" at the other guy. He saved the sale by not doing that but probably should have taken the controls.
wjcandee
William Candee 1
Well, this is totally wrong. Take a look at my post above as to what they were doing, why, and who they were. The aircraft was intentionally fully cross-controlled (look at the yoke) and decelerating faster than a normal stall test.

I would fly in the right seat with Bear flying any day (if he were still around). Also, when criticizing the recovery technique, consider that it's a t-tailed aircraft with tabs.

bentwing60
bentwing60 1
Source William, source. The video is essentially unsourced and the bulk of the legitimate ATP's commenting on this thread have been in agreement that even in our meer non test pilot roles, what we saw said "that ain't right". If they really were test pilots doin what you said, it's no wonder it took so long to get out. And it ain't like they were in uncharted waters in an airframe that was first certified in 1965.
ArthurNetteler
Arthur Netteler 1
Object LESSON... DON'T STALL! The DC9 and B717 did not like to be STALLED!
BuddyCox
BuddyCox 1
Boeing bought McDonald-Douglas and renamed the DC-9 and variants like S-80 to B-717.
Those guys were probably Functional Check Flight pilots testing the stall warning system. Stalls are prohibited. The way it should have worked a 'stick shaker' would start shaking the stick, the the stall warning would flash along with audio 'Stall, Stall, Stall them the stick pusher kicks in to that it won't stall. None of that appeared to happen. The 'Clicker' sounded and the 'Over Speed' aural warning sounded. The probably over 'G' the plane. If it had been a military plane, it would be on display at the main gate.
sparkie624
sparkie624 1
That was obviously an intentional maneuver... weather it was approved or not.. I would say so... Note the way they congratulated each other, the fact that video was ready and a prompt reading of the FDR. Those guys were operating under permission, but I would not put that in a recommended maneuvers column.
djames225
djames225 0
The predecessor "name" for the B-717 was MD-95 but that model designation never made it to an aircraft necause Boeing and MD had merged prior to the first craft being finalized...the DC-9, MD-80 and MD-90 still retain their perspective model names and signatures..this procedure was a test of the B-717 model.
wjcandee
William Candee 0
Doing a little research on this, it appears that this is a McD test pilot crew in the 1998-1999 time frame. Boeing had owned McD by the time they rolled out the first MD95/717, but remember that McD was still a subsidiary at that point with its existing lines of authority and organization. So these are McD guys in the cockpit, apparently ex-Navy Vietnam fighter pilot Randy Wyatt in the right seat, who went on to be a Boeing test pilot, including on the 747LCF, and Gary "Bear" Smith in the left seat. Bear was a Blue Angel and still active in the Naval Reserves, and was a McD test pilot. He died in 2005 in his Super Decathalon while giving advanced flight instruction to an instrument-rated private pilot near Oroville; apparently the student was at the controls.

It appears that this was Developmental or Certification stall testing on the aircraft, specifically the aggravated/accelerated entry points where the speed is changed at more than 1 knot per second. According to a guy that did the same tests on the MD90, having the aircraft depart like that during the accelerated entry points wasn't unusual.
PJSalazar
Philippe-Joseph Salazar 0
This is training. Real training.

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