Cedarjet From United Kingdom, joined May 1999, 7812 posts, RR: 54 Posted (13 years 5 months 2 weeks 6 days 20 hours ago) and read 4143 times:
A day or two ago (don't know the exact time or day), an Emirates A310 did a go-around on runway 12 Right at Dubai, then stalled due to an incorrect trim setting in a nose high (45 degrees) attitude, with an airspeed of 69 knots, fell to the right, and just missed the control tower. The crash alarm was activated in the tower, (with controllers running for the stairs and diving for cover, apparently). The aircraft recovered and then pitched nose high again before finally making a full recovery and landing safely on a second approach. The crew and forty of the pax taken to hospital.
Far out. Apparently the co-pilot was flying, and was inexperienced on type. It would seem that the A300-600 and A310 are tricky beasts during go-arounds, maybe the China Air Lines crashes (both were this exact scenario) were harbingers of a wider phenomenon?
Anyway, thought some of you might enjoy this little tale, sure gets the blood pumping. Glad I wasn't on board. (Did you hear about the SQ 747-400 that stalled after takeoff from Vienna a year or two ago?)
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz
Kaitak From Ireland, joined Aug 1999, 12177 posts, RR: 35 Reply 1, posted (13 years 5 months 2 weeks 6 days 20 hours ago) and read 3987 times:
All things considered, this is best avoided. I would not like to be in this crew's shoes when they sit down with the chief pilot (he'll be the one with smoke coming out of his ears) to explain what the &%$" they were doing.
I didn't hear about the SQ incident, but this reminds me of an incident in Moscow about seven years ago. A "German" A310 - no airline mentioned, but my money's on Interflug, the old DDR airline - was going around at SVO due to another aircraft on the runway. The aircraft performed its usual g/a, without a problem, but for the crew, the pitch was very alarming, possibly their first in an A310 (which leads me to believe it was an IF aircraft - the crew would have been used to about 10 degrees at most on an IL6, whereas a 310 can climb out at over 20 degrees!). What followed was a frightening few minutes of aerobatics, which included a speed of about 30 knots at some alarming angle; the aircraft landed safely.
Shankly From United Kingdom, joined Jan 2000, 1517 posts, RR: 1 Reply 2, posted (13 years 5 months 2 weeks 6 days 19 hours ago) and read 3936 times:
If this really was a stall then these people are lucky bunnies as that aircraft would have dropped like a stone. Sounds like what ever happened to get in that mess, at least the crew got their stick forward. They must also have had some reasonable altitude. Is the A310 FBW?
Kaitak. Wasn't that a LH A320 that did the barnstorming in Moscow? Something to do with the Flight Computer as similarly happened to a Tarom A310 which did some rather spectacular aerobatics on film whilst landing at Paris a few years ago (not the one that crashed).
I do actually like the A310, but it strikes me that it does seem to have more than its fare share of prangs.
CX flyboy From Hong Kong, joined Dec 1999, 6454 posts, RR: 56 Reply 3, posted (13 years 5 months 2 weeks 6 days 19 hours ago) and read 3922 times:
I don't think anyone should be questionning the pilot's ability. For all we know, maybe the chief pilot thanked him for saving the day. We really don't know what happened and should refrain from speculation unless we state it is merely that.
We know that A300/A310s have had a few problems. These maybe design faults and not just pilot ability every time an incident happens.
Cedarjet From United Kingdom, joined May 1999, 7812 posts, RR: 54 Reply 4, posted (13 years 5 months 2 weeks 6 days 18 hours ago) and read 3869 times:
I think the Moscow Incident was Interflug too, Mr K. Tak. The bloody thing went vertical (yes) and slowed to 30 kts, and this happened three times. The A310 must be incredibly strong to have survived such a situation.
It isn't a particularly accident prone type, there have been a few messed approaches (Thai have killed two perfectly servicable A310s in landing accidents) and Tarom managed to fly one upside down (180 degree roll) after an engine failure during climbout from Bucharest before crashing inverted into the Romanian countryside. I can't think of any others.
I think the A310 has the same control system as the A300-600R, ie FBW but a yoke in a Porsche-designed cockpit. Nice aircraft.
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz
HeavyJet From , joined Dec 1969, posts, RR: Reply 5, posted (13 years 5 months 2 weeks 6 days 18 hours ago) and read 3867 times:
>>The aircraft performed its usual g/a, without a problem, but for the crew, the pitch was very alarming, possibly their first in an A310...<<
Remember, in the course of their sim training the crew did multiple GA's..both normal and non-normal. I seriously doubt the "normal" g/a pitch was "alarming" to them.
Alittle insight to automated airplanes. Folks coming from analog (round-dial instrument) type airplanes are use to hand flying g/a's. Their tendency when transitioning to automated airplanes is to disconnect the autopilot/autothrottle systems when initiating a go-around. Automated airplanes like the B757/767 and A300/310 can fly go-arounds on the autopilot.
Having flown/taught the B75/76 and recently been checked out in the A300-600 let me share some of my observations. First, an automated g/a is a fairly simple manuever under normal situations and the autopilot does a beautiful job. All the pilot has to do is select the g/a lever on the thrust levers and than select the "Lnav/nav" mode at 400ft sit back and enjoy the ride. The autopilot will fly the g/a profile including the missed approach course and hold that's in the FMC data base. This is a very basic explanation as there's alittle more to it but hopefully you get the idea.
Now, the caveats. All four airplanes listed above are very overpowered. Also, with the wing mounted engines (thrust line below the center of gravity), there is a big tendency for the pitch attitude to increase substantially with the application of power.
The nice thing about the B75/76 is that when the g/a button is pressed, the autothrottles will command and give the pilot a power setting that will give him around 2000fpm climb at g/a speed. This is about half of total available power (I said it was overpowered...didn't I!). Keep in mind the pilots can override this at any time, however, it makes for a nice easy transition from the landing phase to the g/a phase. This also keeps the changing pitch attitude more manageable to control.
The A300/310 basically works the same way accept the Airbus gives you max g/a power from the start instead of around half. This tremendous increase in power and associated pitch attitude change has caught more than one pilot alittle off guard. I've found on the A300 that your actually pushing forward on the yoke as power is coming up to counter the natural pitch increase with increasing power.
So, having said that, there was a China Air (I believe that was the airline)A300 accident that comes to mind which, on an attempted g/a the aircraft continued to pitch up until stalling and crashing on or near the runway. The f/o was attempting an autopilot g/a or maybe he accidently push the g/a lever while trying to turn the autothrottles off to land. I've seen that happen. The increase power/increase pitch attitude caught him off guard. He attempted to push the yoke forward to get the nose down. The autopilot simply trimmed against his pressure on the yoke unti it had almost full nose up trim. When they fianally dissconnected the autopilot the plane was severely out of trim/altitude and speed.
While the autopilot g/a is straight forward, you still have to stay ahead of the airplane. If things start to go wrong...remember, it's just an airplane! Turn the automation off and hand fly it like anything else until things settle down.
HeavyJet From , joined Dec 1969, posts, RR: Reply 8, posted (13 years 5 months 2 weeks 6 days 16 hours ago) and read 3803 times:
>>Thank you Heavyjet, it is not often that we get a professional response on this board (by that I mean a response from aircrew).<<
Your welcome Tailscraper. Actually I've posted several times on varies subjects.
>>I have experienced a GA at DXB on an EK A300 inbound from MAN-normal GA, landed safely thereafter. No doubt there will be a thorough de-brief for the crew concerned.<<
GA's are not uncommon. I guess I'm alittle confused by the "thorough de-brief for the crew" line in your post. Do you mean the crew involved in the original post or just any crew that has to do a GA? If you mean the crew in the original post, which I believe you did, your right...there probably will be a full review.
MD-90 From United States of America, joined Jan 2000, 8479 posts, RR: 13 Reply 10, posted (13 years 5 months 2 weeks 6 days 13 hours ago) and read 3756 times:
I'm surprised that it stalled at/around 69 knots. That's way low for an airliner! Of course, it was probably light on landing since it would've burned most of it's fuel off, but still, a 727 with it's complex system of flaps/slats would be hard pressed to duplicate that performance. I seriously doubt that the climb angle was 45 degrees. The wing would certainly stall before it got that high. If I were in charge, I'd make the pilots undergo a stiff checkride and if they didn't perform extremely well, I'd fire them. You fly a heavy jet by the book and this certainly was not by the book. They're lucky they didn't enter a deep stall or a spin. Either would have probably killed everyone aboard. I do stalls and spins in our Kolb, but it takes all of about 250 ft. to recover from a spin. In an A310, I'd estimate it more like 5,000 ft.
J32driver From United States of America, joined May 2000, 399 posts, RR: 1 Reply 11, posted (13 years 5 months 2 weeks 6 days 12 hours ago) and read 3742 times:
Heres a question stemming from my lack of knowledge about the flightdeck of an Airbus. Can you turn off all the gee whiz crap and fly it without interference from the autopilot? I hear quite a bit about pilot's becoming confused and fighting the autopilot's on the Airbus products, but you never hear about that on a Boeing... why is that. I can see one incident where the crew isn't smart enough to disconnect the autopilot, but it sure does seem to be a recurring theme here.
This question is specifically for Heavyjet since you've instructed in both brands of aircraft.
Cedarjet From United Kingdom, joined May 1999, 7812 posts, RR: 54 Reply 12, posted (13 years 5 months 2 weeks 6 days 11 hours ago) and read 3739 times:
Answering a few points above: airliners actually have surprisingly low stall speeds - I know the VC10 was 90 kts, and a DC10 is about 105 (these are full-flap speeds). The Interflug (Kai Tak and I think it was them) A310 that went out of control over Moscow due to an incorrect trim setting hit speeds as low as 30 kts and pitch attitudes of over 90 degrees. I don't doubt the Emirates aircraft managed 45.
I may have missed something in the definition but deep stalls are really only the province of the t-tail. My definition of a deep stall is where the elevators are masked by the slipstream of the stalled wing, rendering them ineffective, depriving the pilot of the ability to reduce pitch and therefore recover. This doesn't happen on low-tailplane types, because if the nose is high, the tailplane will always be below the wing, keeping them clear of turbulent air.
A jet airliner would lose about 400 ft in a stall if recovery was initiated immediately. A Singapore Airlines 747-400 stalled at 800 ft after take-off from Vienna and missed the ground (Captain flying...talk about firing someone's arse). Another Singapore Airlines 747-400 was allowed to stall during the cruise at FL350 on a long haul flight to Europe and dropped 1,000 ft, bearing in mind the much thinner air at 35,000 ft. The recovery was initiated at 34,600 ft, BTW.
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz
HeavyJet From , joined Dec 1969, posts, RR: Reply 13, posted (13 years 5 months 2 weeks 6 days 9 hours ago) and read 3718 times:
>>Can you turn off all the gee whiz crap and fly it without interference from the autopilot?<<
Now I'm only talking about the A300/310 models of Airbus. I know nothing about the newer generation of Buses and their automation.
The answer to your question is "yes", you can turn all the "crap" off. You simply revert to hand flying and manually moving the throttles...just like any other airplane.
I think one of the problems with the autopilot(s) on the A300/310 is the required force (push/pull) on the yoke by the pilot is greater than on the Boeings. The pilot can end up fighting for control over the autopilot if he doesn't use the disconnect button on the yoke, as some of the Airbus accidents have proven. Pushing and pulling on the yoke IS NOT the correct way to normally disconnect the autopilot(s). It's only a safety feature. Autopilots are normally diconnected by a push button on the yoke and if pilots of the accident aircrafts had used that button first it probably would have solved alot of their problems.
Getting back to the push/pull force required on the yoke by the pilot to disconnect the autopilot. Remember Eastern 401 (L1011) that crashed in the Florida everglades? The Captain bumped the yoke as he got up out of his seat to investigate a problem. The autopilot disconnected too easily along with the fact there wasn't any autopilot disconnect warnings that airliners have today. EA 401 simply flew straight and level into the glades because no one noticed the autopilot wasn't on. That accident change the way autopilots are designed and the warnings associated with them. They now require more force on the yoke to disconnect so a simple "pump" on the yoke doesn't create problems and there's also a warning anytime the autopilot is disconnected for any reason.
>>This question is specifically for Heavyjet since you've instructed in both brands of aircraft.<<
I've only instructed on the B75/76. I just got typed on the A300 last week at FlightSafety and will begin instructing in about a month. Our first A300 arrives in a couple of weeks. The instructors down at FltSafety talked about the problems teaching some of the asian carrier pilots. For one, there's a big language problem. Keep in mind all warnings and checklists are displayed on a ECAM screen in english. While the crewmembers are required to speak english (at least on the radio) many struggle. You can see where confusion might arise during a non-normal situation if everything's in English and that's not your 1st language. During stressful situations you'll probably revert back to speaking your native tongue while trying to read messages on the ECAM and checlist that are in English, some items requiring immediate action. Combine that with culture atmosphere in many of the asian countries of a very authoritarian Capt and a new young inexperienced F/O flying an automated airplane. Not exactly the best CRM environment. Mistakes are made under stress and if you don't understand the automation it's very easy to get behind the power curve...both you and the airplane's.
MD-90 From United States of America, joined Jan 2000, 8479 posts, RR: 13 Reply 14, posted (13 years 5 months 2 weeks 6 days 9 hours ago) and read 3705 times:
I remember reading in Airways a 727 asked (exasperatedly) to ATC, "Do you guys know what the stall speed of a 727 is?" To which ATC replied, "If you ask the guy on your left I'm sure he'll tell you." This was after advising them to slow 150 knots. If recovery is initiated immediately, you can get out of a stall in a matter of seconds. But if you're so far behind the airplane that you let the speed decay to 69 knots, something's clearly wrong, and you might not begin stall recovery soon enough. And as for spins, you just don't deliberately do them in a jet. The problem is that the wings are swept, this encourages the air to detach and slip across the wing. Okay, that's not a very good explanation, but that's almost literally what happens. That why the 727 has two leading edge cuffs.
Notice the leading edge cuff where the sweep angle of the wing changes.
Hmmmm... From Canada, joined May 1999, 2095 posts, RR: 5 Reply 16, posted (13 years 5 months 2 weeks 6 days 8 hours ago) and read 3683 times:
Let me ask this, with all the safety override automation on these planes, especially Airbus, how is it that the plane was allowed to reduce airspeed below, much less significantly below, stall speed? Should not the autothrottle always make sure there is enough thrust to keep the thing at least 120 knots with flaps out when landing? Or put it this way, why would the computer allow a nose high attitude with airspeed so low? It seems almost as if there isn't enough computerized safety override on the Airbus if it allowed such a scenario to play out.
An optimist robs himself of the joy of being pleasantly surprised
CX flyboy From Hong Kong, joined Dec 1999, 6454 posts, RR: 56 Reply 17, posted (13 years 5 months 2 weeks 6 days 7 hours ago) and read 3678 times:
In quite a few instances, it is much better to let the autopilot continue flying the aircraft. They normally do a very good job, and there is no need to disconnect and fly manually. Of course, this is not for all situations, but there have been situations where disasters have happened or nearly happened due to this.
For example, remember the China Airlines 747sp that did aerobatics over the Pacific? This occured because a spoon or something had been left next to the aileron trim, and a tray was pushing the little lever. Slowly, the autopilot was putting in aileron to counteract it. The pilots finally noticed, and disconnected the A/P. They did not have aileron in, ready for it, so the aircraft flipped over and went into a spiral dive. Luckily they recovered (I had a relative on that flight!). If the A/P is keeping the aircraft in the air, by interfere. In all liklihood, something is wrong, and any pilot who turns off a perfectly good autopilot to increase his workload threefold and try to solve the problem at the same time is nuts.
By the sounds of it, with all these A300/310 incidents, the A/P was going to fly a perfectly normal GA, and the pilots interfered, did not anticipate the pitch change and crashed or stalled. Am I right in saying that the older airbuses don't have all the protection offered by the newer models?
On the 747-400, like the 757 mentionned earlier, pressing TOGA gives you 2000fpm climb. A second press gives you full TOGA. Also, pushing and pulling will not disconnect a 747-400 A/P. Only angles of bank on the yoke greater than 25degrees will do this...or if you deliberately split the elevator trim buttons (i.s. one up, one down), this will trip the AP also.
GreenArc From United States of America, joined May 2000, 78 posts, RR: 1 Reply 18, posted (13 years 5 months 2 weeks 6 days 7 hours ago) and read 3670 times:
This clip appeared in Airliners. I believe the airline was Interflug.
"Airliners Magazine", Winter 1992
Following an autopilot-coupled go-around, the pilot attempted to counteract the autopilot's programmed pitch-up by pushing forward on the control column. (In most circumstances pushing on the control column disengages the autopilot but automatic disconnect is inhibited in go-around mode. The autopilot should be disconnected or a mode other than go-around should be engaged through the FCU-Flight Control Unit).
As a result of the control inputs, the autopilot trimmed the stabilizer to 12° (nose up) to maintain the go-around profile, but the elevator was deflected 14° (nose down). After climbing about 600ft (to around 2100ft) the autopilot captured its preselected missed approach altitude and disconnected, as the go around mode was no longer engaged. In the next 30 seconds, the grossly mistrimmed A310 pitched up to 88° and airspeed dropped to less than 30kt. (The stall warning activated then canceled itself as the airspeed fell below usable computed values and the autothrottle system dropped off.) At 4,300ft, the A310 stalled, pitching down to -42° while pilot-applied control inputs showed full up elevator. Airspeed increased to 245kt then the aircraft bottomed out at 1,500ft, pulled + 1.7g, then climbed rapidly.
The second pitch-up reached 70° followed by a stall 50 seconds after the first. The nose dropped to -32° and airspeed rose to 290kt and the aircraft bottomed out at 1,800ft. On the third pitch-up (to 74°), the A310 climbed to 7,000ft then stalled again, about 60 seconds after the second stall. This time airspeed reached 300kt in a -32° nose down attitude before the aircraft leveled off at 3,600ft.
The fourth pitch-up reached 9,000ft but this time the crew's use of thrust and elevator control (and very likely retrimming the stabilizer) prevented a stall and the A310 leveled off at 130kt. Speed then increased accompanied by another milder pitch- up to 11,500ft where control was eventually regained.
All aircraft systems operated in accordance with design specifications. The reaction of ATC (the incident happened at Moscow) or the passengers is not recorded.
Skystar From Australia, joined Jan 2000, 1363 posts, RR: 3 Reply 19, posted (13 years 5 months 2 weeks 6 days 3 hours ago) and read 3639 times:
Remember, the plane in question here is the Airbus A310 - part of the "pre FBW" Airbus era. It does not have the flight envelope protection systems that you are talking about. It's not the "supercomputer plane where the pilots have a picnic up front". No sidesticks, just yokes.
The modern Airbuses, such as the 320, 330/340 have such a system. It would be theoretically impossible for such an event to occur in these planes as the systems will only provide a pilot with the maximum safe nose up pitch - the max AoA safe limit that will provide maximum lift.
(someone correct me here if I am wrong). IIRC, the FBW (fly by wire) Airbuses have a limit on pitch which is something like 30° (but I'm pretty sure its AoA and G limited) and up to 67° bank (I'm sure of this one). These systems keep the aircraft within a safe flying envelope - not too fast, not too slow, not too stressful, etc.
These aircraft's systems will carefully monitor approach speeds, keeping the aircraft in a safe flight envelope until a low altitude (~50-100ft) and from then on the aircraft assumes it is in a landing phase - remember, if this were not the case, flaring could be a pain with the aircraft's engines spooling up, ie. the protection systems are no longer active. In other words, the plane allows the pilot to decelerate to slower speeds. Touchdown speeds for an A320 at "typical weights" are around 120knots in my experience. It is often said that ideally you should stall just as the wheels touch down - given that the Airbus FBW systems apply power, etc on the onset of a stall, landing could be a real pain.
HeavyJet's has made some excellent comments on the topic, especially in relation to the A300/310. Seems like G/As in these planes are a bit of a pain.