Can you guess the incident?

[Cam]

In the novel AIRFRAME, Michael Crichton writes about a fictional airliner that has a mysterious accident (based on a real incident).

In the early hours on Monday morning, TransPacific Airlines Flight 545, enroute from Hong Kong to Denver, experiences a horrifying event. Three people are killed and countless others are injured as their plane ascends and descends in a terrifying roller-coaster ride reportedly due to turbulence.

The plane's manufacturer, Norton Aircraft dispatches an in-house Quality Assurance Vice President, Casey Singleton, to discern what exactly occurred—and most importantly, who is to blame.

Eventually, the cause of the disaster turns out to be a combination of faulty and counterfeit parts and human error. While in flight, the airplane's computer and safety systems worked perfectly, detected the fault, and attempted to automatically correct the plane to compensate.

The pilot had let his son, also a pilot, take the controls. Just before the incident, while the pilot was out of the cockpit, an error was detected and the autopilot attempted to engage. The son, being less experienced and not certified for the N-22, panicked and tried repeatedly to fly against the autopilot, causing the catastrophic accident.

What real life incident do you think this is from?

**EDIT** To add, it is probably a combination of incidents since it is a work of fiction.

[Tecnanaut]

Eventually, the cause of the disaster turns out to be a combination of faulty and counterfeit parts and human error. While in flight, the airplane's computer and safety systems worked perfectly, detected the fault, and attempted to automatically correct the plane to compensate.

The Air Transat A330 that ran out of fuel over the Atlantic?

The pilot had let his son, also a pilot, take the controls. Just before the incident, while the pilot was out of the cockpit, an error was detected and the autopilot attempted to engage.

That Aeroflot flight where the PIC let his son take the controls.

[HalcyonDays]

That Aeroflot flight where the PIC let his son take the controls.

....although the Aeroflot pilot's son wasn't himself a pilot and was a teenager or even younger.

[Airfoilsguy]

I seem to remember a 727 pilot who was screwing around with his flaps or slats at altitude who basically caused a very similar incident to happen



Found it

TWA Flight 841 entered an uncontrolled maneuver at FL390. The aircraft descended to about 5,000 feet in about 63 seconds before the flightcrew regained control. About 22:31, the flightcrew made an emergency landing at Detroit.
The flight was cruising in visual flight conditions at night at FL390 when the uncontrolled maneuver began; there was no turbulence. There was a cloud layer near FL200 and, at 21:55, the reported weather at Saginaw was 500-foot overcast with 3 miles visibility in light snow; small breaks were reported in the overcast. Analysis of the evidence indicated that the uncontrolled maneuver began about 2147:47 with isolation of the aircraft's No. 7 leading edge slat (on its right wing) in the extended or partially extended position. During the preceding 14 seconds, the aircraft had rolled slowly to the right to about 35° of right bank and was returned to near wings level flight. Thereafter, the aircraft rolled again to about 35° of right bank in about 4 seconds. About 2147:51, the right roll was stopped near 35° of bank for a few seconds. At that time, the aircraft reached a condition wherein mach number, angle of attack, and sideslip combined to reduce the aircraft's lateral control margin to zero or less, and the aircraft continued to roll to the right in a descending spiral. During the following 33 seconds, the aircraft completed 360° of roll while descending to about 21,000 feet. The aircraft entered a second roll to the right during which the No. 7 slat was torn from the aircraft. Control of the aircraft was regained about 21:48:58 at an altitude of about 8,000 feet.
PROBABLE CAUSE: "The isolation of the No. 7 leading edge slat in the fully or partially extended position after an extension of the Nos. 2, 3, 6, and 7 leading edge slats and the subsequent retraction of the Nos. 2, 3, and 6 slats, and the captain's untimely flight control inputs,to counter the roll resulting from the slat asymmetry. Contributing to the cause was a preexisting misalignment of the No. 7 slat which, when combined with the cruise condition airloads, precluded retraction of that slat. After eliminating all probable individual or combined mechanical failures or malfunctions which could lead to slat extension, the Safety Board determined that the extension of the slats was the result of the flightcrew's manipulation of the flap/slat controls. Contributing to the captain's untimely use of the flight controls was distraction due probably to his efforts to rectify the source of the control problem."
A.o. the ALPA did not agree with the NTSB findings. A complex interaction that involved the tightly coupled response of lateral and directional flight controls on the B727-100 aircraft was claimed to have caused the crash.

http://aviation-safety.net/database/...?id=19790404-0

[JordanD]

I seem to remember a 727 pilot who was screwing around with his flaps or slats at altitude who basically caused a very similar incident to happen



Found it



http://aviation-safety.net/database/...?id=19790404-0

There was a similar incident in an MD-11. I don't remember the specifics off the top of my head, but either the FA or the FO bumped the slat controls and deployed them at cruise. If I'm not mistaken at least one passenger died from hitting their head on the ceiling.

[andrasz]

There was a similar incident in an MD-11. I don't remember the specifics off the top of my head, but either the FA or the FO bumped the slat controls and deployed them at cruise. If I'm not mistaken at least one passenger died from hitting their head on the ceiling.

1993, April 6. A China Eastern Airlines MD-11, on a flight from Beijing to Los Angeles, suffered an inadvertent deployment of the leading edge wing slats, while in cruise flight about 950 miles south of Shemya, Alaska. The autopilot disconnected and the captain attempted manual control. The plane progressed through several pitch oscillations, losing 5,000 ft. of altitude. Two passengers were fatally injured; 149 others received various injuries ranging from light to severe. Seven crewmembers were also injured, including one flight attendant who suffered severe brain damage. The captain declared an emergency and diverted to the Air Force base at Shemya. There was no external structural damage, but the interior cabin did sustain substantial damage.
During its investigation of this accident, the NTSB found “12 incidents of inadvertent or uncommanded in-flight slat extensions and 2 events on the ground involving MD-11 airplanes.” The NTSB found the probable cause of the accident to be:

…the inadequate design of the flap/slat actuation handle by the Douglas Aircraft Company that allowed the handle to be easily and inadvertently dislodged from the UP/RET position, thereby causing extension of the leading edge slats during flight. The captain’s attempt to recover from the slat extension, given the reduced longitudinal stability and the associated light control force characteristics of the MD-11 in cruise flight, led to several violent pitch oscillations.

Contributing to the violence of the pitch oscillations was the lack of specific MD-11 pilot training in recovery from high altitude upsets, and the influence of the stall warning system on the captain’s control responses. Contributing to the severity of the injuries was the lack of seat restraint usage by the occupants. [passengers did not have their seat belts fastened]

The stall warning system was cited as a contributing factor because its activation told the pilot that he must push the nose down even more, but that was the wrong action for a plane with relaxed stability designed into the pitch axis.

[Gabriel]

[SPOILER WRNING]

In the case of the book Airframe, however, Norton (read MD) had already introduced (and mandated retrofit) changes of the flaps/slats lever of the N22 (read MD-11) to prevent the recurrence of such inadvertent/uncommanded deployments of the slats.

IIRC the problem here was a faulty proximity sensor that sent a false "slats disagree" warning to the flight crew. The procedure to handle a slats disagree warning in cruise was something like:
- Extend slats
- Let the autopilot handle the flight
- Retract slats

When the FO saw the "slats disagree" warning, he started the procedure by extending the slats. The autopilot pitched down to prevent the airplane from climbing, but the captain's son that was in the left seat didn't know what was going on and disconnected the autopilot to prevent what he thought was an uncommanded pitch, and while trying to maintain the attitude induced severe pitch oscillations that involved high G forces (positive and negative).

So it was not an ucommanded/inadvertent slats extension, like the cases investigated by the NTSB, but a commanded one, followed by a non-authorized pilot trying to "recover" from something that needed no recovery.

I don't know of any real incident like that.

By the way, the counterfeit part found during the investigation in the novel was a thrust reverser. It was suspected that the cause of the accident was an uncommanded in-flight reverser deployment (again, any similitude with a real circumstance is not just coincidence, remember Lauda's 737?) and that the counterfeit reverser was involved. But finally it was the slats issue and the counterfeit part was not guilty.

[Verbal]

Was it the Chinese 747 that went into a supersonic nosedive over the Pacific, recovered, and landed safely at SFO?

[Dmmoore]

Was it the Chinese 747 that went into a supersonic nosedive over the Pacific, recovered, and landed safely at SFO?

Yes, A 747 SP

[tynopeb]

Yes, A 747 SP

It was China Airlines Flight 006 at 02/19/1985 enroute from TPE to LAX. It indeed was a 747-SP09 (N4522V, cn. 22805/564). It was repaired and put back into service about one year after the incident.
Look at the Pic in the upper right corner!! Simply horrifying....

[Alberto U.]

So it was not an ucommanded/inadvertent slats extension, like the cases investigated by the NTSB, but a commanded one.

Although for completely different reasons (in one sentence, icing on the Pitot and lack of warning to the crew, who thought they were losing speed) another case happened in Argentina/Uruguay on a Austral DC-9.

http://aviation-safety.net/database/...?id=19971010-0

[Gabriel]

Although for completely different reasons (in one sentence, icing on the Pitot and lack of warning to the crew, who thought they were losing speed) another case happened in Argentina/Uruguay on a Austral DC-9.

http://aviation-safety.net/database/...?id=19971010-0

Tu grato nombre...

[P3_Super_Bee]

[SPOILER WRNING]

In the case of the book Airframe, however, Norton (read MD) had already introduced (and mandated retrofit) changes of the flaps/slats lever of the N22 (read MD-11) to prevent the recurrence of such inadvertent/uncommanded deployments of the slats.

IIRC the problem here was a faulty proximity sensor that sent a false "slats disagree" warning to the flight crew. The procedure to handle a slats disagree warning in cruise was something like:
- Extend slats
- Let the autopilot handle the flight
- Retract slats

When the FO saw the "slats disagree" warning, he started the procedure by extending the slats. The autopilot pitched down to prevent the airplane from climbing, but the captain's son that was in the left seat didn't know what was going on and disconnected the autopilot to prevent what he thought was an uncommanded pitch, and while trying to maintain the attitude induced severe pitch oscillations that involved high G forces (positive and negative).

So it was not an ucommanded/inadvertent slats extension, like the cases investigated by the NTSB, but a commanded one, followed by a non-authorized pilot trying to "recover" from something that needed no recovery.

I don't know of any real incident like that.

By the way, the counterfeit part found during the investigation in the novel was a thrust reverser. It was suspected that the cause of the accident was an uncommanded in-flight reverser deployment (again, any similitude with a real circumstance is not just coincidence, remember Lauda's 737?) and that the counterfeit reverser was involved. But finally it was the slats issue and the counterfeit part was not guilty.

He never diconnected the autopilot and that was the problem... the autopilot was counteracting what the pilot was inputting into the stick. If you remember when they took the reporter up during the test flight. they recreated the the incident, and to fix the ocolations and return to straight and level flight the test pilot simply removed his hands from the control stick and the autopilot brought the plane back to straight and level.

[uy707]

Could also be a JAL 747 which experienced severe turbulences while enroute to HNL about two decades and half ago.