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A37575
19th Jul 2009, 01:00
Researching GA incidents/accidents. Does any reader have info or link on the near disaster to a United Airlines B737 (probably 20 years ago?) that did a VMC go around which resulted in a dangerous pitch attitude. I believe both pilots were qualified test pilots. the The pilot rolled the wings to get the nose to fall and the recovery (I understand) was made at 30 feet. It was after that incident that United Airlines introduced a training policy of unusual attitude's which they named Advance Qualification Programme (AQP).

Tmbstory
19th Jul 2009, 08:55
A37575:

In my own experience there was a similar upset on the above date at Sydney Airport in a Falcon.

We had a pitch up to about 60 to 80 degrees and managed to recover from the first upset just before ground level.

The details were posted in DG&P GA and Questions on 15th September 2007 post number #63 and the title is Dance of the Falcon.

Regards

Tmb

CaptainSandL
19th Jul 2009, 10:27
I would be fascinated to hear about the UA event.

Any similarity with this one:

Air Accidents Investigation: 3/2009 G-THOF (http://www.aaib.gov.uk/publications/formal_reports/3_2009_g_thof.cfm)

The 737 can be a handful in a go-around.

jleorich
19th Jul 2009, 10:42
I'm fairly certain the incident to which you are referring occured at SFO.

Jimmy Do Little
19th Jul 2009, 10:55
Between 1980 and 1990 there were 9 incidents involving United Airlines B737's. Following a search of the NTSB database, the only incident found in the query involving anything close to this, is ....


NTSB Identification: CHI88IA015A.
The docket is stored on NTSB microfiche number 38705.
Scheduled 14 CFR UNITED AIRLINES
Incident occurred Thursday, October 29, 1987 in CHICAGO, IL
Probable Cause Approval Date: 7/10/1989
Aircraft: BOEING 737-322, registration: N305UA
Injuries: 147 Uninjured.
.... AIR WISCONSIN FLT 954 (FOKKER F27) HAD BGN A VISUAL APCH TO 9R. AT 1545:23, AFTER COORDG WITH NLC, SLC CLRD THE F27 TO CIRCLE (SIDE STEP) FOR A LNDG ON RWY 9L & CHG FREQ TO NLC. THE FINAL APCH PATH (EXTD CTRLN OF 9L) CROSSED OVR RWY 32L. AT 1546:53, SLC CLRD THE 737 TO TKOF. AT APRX V1 (133 KTS), THE 737 PLTS SAW THE F27 CONVERGING, AS IT WAS ABT TO CROSS THEIR INTENDED TKOF PATH. THE F27 CREW DID NOT SEE THE 737. THE 737 CAPT DID NOT THINK HE COULD SAFELY CROSS UNDER THE F27 OR ABORT THE TKOF. HE ELECTED TO AVOID THE F27 BY CLBG OVER THE OTR ACFT RATHER THAN PASSING UNDER IT.



Aviation Accident Database Query (http://www.ntsb.gov/ntsb/query.asp#query_start)

A37575
19th Jul 2009, 11:38
THE 737 CAPT DID NOT THINK HE COULD SAFELY CROSS UNDER THE F27 OR ABORT THE TKOF. HE ELECTED TO AVOID THE F27 BY CLBG OVER THE OTR ACFT RATHER THAN PASSING UNDER IT.

Thanks for the replies so far. Any specific details on the amount of pitch up and recovery action would be handy.
Re the "Dance of the Falcon" at Sydney. Frightening incident and to reach those attitudes and still recover must have been first class flying skills. I was unable to find it on the Pprune search engine although that might be due to my incompetence at placing the right words.

A37575
19th Jul 2009, 11:43
In my own experience there was a similar upset on the above date at Sydney Airport in a Falcon.

We had a pitch up to about 60 to 80 degrees and managed to recover from the first upset just before ground level.


Would it be possible for you to describe here on Pprune what caused the Falcon pitch up and the cirumstances? I am certain many pilots would be very interested and could learn lessons from it.
A37575

Spooky 2
19th Jul 2009, 13:17
AQP has nothing to do with this incident nor for that matter is it directly aimed at unusual attitude recovery which by the way is not the same as Upset Recovery Training which will be coming at a theather near you soon accorfing to the FAA.

BOAC
19th Jul 2009, 20:09
Tmbstory

http://www.pprune.org/dg-p-general-aviation-questions/281726-west-plane-safe-after-engine-trouble-4.html

Tmbstory
20th Jul 2009, 08:19
BOAC:

Yes, that is the incident, I was replying to" The West: Plane safe after engine trouble" and included my story " Dance of the Falcon". With hindsight I should have made it a new thread..

It certainly got my attention and we were lucky to return to speak about the subject.

Regards


Tmb

Tmbstory
20th Jul 2009, 08:32
A37575:

As BOAC was kind enough to point out, the story was posted under my reply to the post "The West: Plane safe after engine trouble" With hindsight I should have made it under a separate thread.

If , after reading the story, more information is required I will supply what I can.

Regards

Tmb

A37575
20th Jul 2009, 12:23
If , after reading the story, more information is required I will supply what I can.

Regards

Tmb

Thanks Tmb. Australian ATSB has no knowledge of the incident on their data base but they suggested it may have been an RAAF incident. I contacted RAAF DFS today and they said they will check their data base and if they find something, hopefully they'll me send a copy of the official report. Your point about the your early Tiger Moth training points to RAAF flying, maybe? 34 Sqn? Was there for seven years in the Sixty's during which time the squadron received their three Mystere's

A37575
20th Jul 2009, 12:55
unusual attitude recovery which by the way is not the same as Upset Recovery Training

Thanks - I was not aware there was a difference. The Civil Aviation Safety Authority of Australia published DA 2342 entitled Flight Instructors Manual. Exercise 17 includes the sub-heading "Recovery from Unusual Attitudes" and the aim of the exercise was to recognise any unusual attitude of the aeroplane by interpretation of the instrument indications and to recover from such attitudes in the minimum time with the minimum loss of height. It further sub-divides into two types of unusual attitude; Those characterised by low speed and those characterised by high speed.

This description is generally consistent with the Boeing 737 FCTM definition of Jet Upset which includes stall recovery, nose high, wings level, nose low, wings level, high bank angles, nose high, high bank angles and nose low, high bank angles. If these are not unusual attitudes then I don't know what is.

By any interpretation I would have thought the terms Jet Upset Recovery or Unusual Attitude Recovery are interchangeable? Like throttles or thrust levers.

Graybeard
20th Jul 2009, 13:51
A UAL IP told me a dozen years ago of one of their 757 on short approach to LAX. The FADEC on one of the engines went to max power, and they did a go around, climbing faster than ATC could clear them. They shut the engine down and landed without further incident.

GB

Tmbstory
20th Jul 2009, 17:32
A37575: Post #13.

The Bureau of Air Safety Investigation Central Office in Canberra, carried out the investigation. I have correspondence from them in 1989 and also a copy of the FDR and CVR for that Flight.

The aircraft was a Falcon 20F serial number 325. An associate of mine at the time mentioned that the report was to be sent to the International Data Bank of incidents / accidents. I do not know if this occured.

My early training on a DH-60M and a DH-82 was carried out at the Western Branch of the Royal Newcastle Aero Club.

Tmb

A37575
21st Jul 2009, 11:37
The Bureau of Air Safety Investigation Central Office in Canberra, carried out the investigation.

Thanks. ATSB had no record but I would have thought BASIS records would automatically be part of the data base. I'll try them again. Was it a RAAF Mystere 20 or civilian version? Was the fault a defective stab trim. I don't know much about the Mystere 20 - did it have a stabiliser trim or an elevator trim?

Checkboard
21st Jul 2009, 12:29
The 737 has a trim-able stabiliser with a hydraulic powered elevator. Trimmable stabilisers are very powerful, they can easily overpower manual (cable) elevators. Hydraulic elevators are much better, but can still be overpowered.

The elevator on the 737 can control the pitch moment of the engines at full thrust, or the moment from rear trim - but not both together.

If the aircraft has slowed on approach due to an autothrottle failure, as in the Bournemouth incident (http://www.aaib.gov.uk/publications/formal_reports/3_2009_g_thof.cfm) or the Amsterdam accident recently, then the autopilot has wound the trim back to adjust for the speed loss. If the pilot attempts a go around without re-trimming in that situation, then the pitch up will overwhelm the elevator. The typical situation is then a pilot holding full forward elevator (with both hands), while watching the pitch increase to a very nose high stall. :eek:

Incidently the Boeing Flight Crew Training Manual, and QRH both suggest that, in the event of an approach to a stall (speed in the dashed red and stick shaker active but no loss of pitch control yet) , if the autopilot is connected, to leave it connected, and simply advance the thrust. Critically the autopilot immediately begins to trim forward at the first application of thrust, so the pitch is controlled, the speed increases and the whole incident is a minor event.

Tmbstory
21st Jul 2009, 13:59
A37575:

The Falcon 20 F model in this incident was a civilian version.

"The horizontal Stabilizer on a Falcon 20 F is a variable- incidence horizonotal stabilizer that is used to trim the aircraft in pitch and is entirely electrical in its operation. Two control circuits, one normal ( operating off a primary bus) and one stand-by (operating off a secondary bus ), control stabilizer movement through separate cockpit switches and wiring. "

Let me know if you manage to find the Basi reference to the incident. ?

Tmb

john_tullamarine
21st Jul 2009, 22:44
can control the pitch moment of the engines at full thrust

One needs to keep in mind that, for high thrust AND high pitch angle, there is a significant nacelle nose pitch up force .. same thing applies with large power prop installations where the force is at the propeller plane.

In both cases this normal (ie right angles to the airflow) force adds a significant nose up pitching moment. The force arises from the change in airflow direction and is much the same as what happens due to the wing's effect on the airflow.

If the effect is sufficiently great, the aircraft will need specific SAS treatment to address the landing missed approach case.