Airbus crash/training flight

[Smilin_Ed]

AoA Data

Please feel free to whack the back of my hand with a ruler if I haven't been paying adequate attention, but I thought two AoA vanes were frozen and we didn't have the data from the third. Where did the AoA data for the graphs come from?

[bsieker]

ChristiaanJ,

Maybe.

I'll take a closer look again. There are some things I cannot quite reconcile.

I cannot even see that the pitch curve as drawn in alph2z's post bears any more than superficial resemblance to the plot from the report.

It is extremely smoothed, the plot in the report has many more bends, which are significant.

If the source really were the plots in the report, I doubt that anything meaningful can be gained by creating smoothed curves from them. With high-fidelity data it would obviously be possible to determine AoA from pitch, speed and altitude, but I doubt that the data as represented in the report's plots is accurate enough for a meaningful analysis.


Bernd

[Lemurian]

alph2z
Can't find a way to compare your graphs to the report.
It seems that the only plot that gels with the graph is the CAS, transformed into m/s and with an intent to plot a continuity below 40 kt (~20m/s).
Furthermore, the pitch vs path are, IMO, quite impossible as they suggest a negative AoA value between your time plots ~83 to 102, which are not supported by your AoA computations and do not match the reported values.
(Pitch - AoA = ~ Path angle )
As for the acceleration values, I'd only take the report time checks of 25:45:15 and 15:45:23 when the CAS went from 98 to 144 kt, hence an acceleration of 23.66m/s over 8 s, or just under 3 m/s/s or .3g against your .4 . That would be nit-picking if it were not for your graphs after your 100 time plots : positive longitudinal acceleration (over .5G at one time) while the airplane is again going through the second stall.
Sorry, I don't buy it.
Maybe your reference zeros should be re-worked.
But nice attempt, nevertheless...I don't have the courage to even start what you did.

[markkal]

Airbus A320 D-AXLA Crash

A320 D-AXLA Crash, Nov 2008

Dear friends,

I have posted 10 days ago in the Italian forum the following thread for discussion but it had drawn no attention at all, with only 2 responses.
Surprising as Italians are quite talkative and always ready to comment any subject...

Am submitting it to you, as it made me meditate quite a lot.

There is a debate, following some accidents and incidents on the basic skills level of airline pilots, one of them that catched my attention is from PJ2 "eklawyer" on another thread:

Quote

"Most of the F/O's I flew with were afraid to disconnect the autothrust. I offered, (when traffic and workload permitted) but very few takers. After a few incidents when the autoflight should have been used, (bad weather, high workload, tired crew), the managers tightened up and made it mandatory that the autoflight remain engaged under all circumstances. Company policy permits manual flight (including a/t's) when workload is low but in practise it rarely happens and is not taught or practised in the simulator or on line checks. I frankly don't know anyone now, who is comfortable disconnecting the autoflight system to fly an airplane. I know for certain that there have been a number of "close ones" precisely because of this lack of competency and understanding.

I think professional pilot associations have handed over the keys to management instead of protecting their professional responsibilities and licenses but clearly I am old and out of touch. No one was listening in 1992 when we introduced the 320 and were instead intoxicated with automatic flight, and no one is listening today.

We give ab initio OTS "pilots" a year of simulator and put them in the right seat and expect them to be of some use to the captain who may as well be doing single-pilot IFR. Imagine an MPL in the circumstances that we have recently seen over the last two years. While we were all "new" on an airplane, there was such a thing as an apprenticeship in the military or more commonly, the bush where real aviation was learned with the help of adrenaline and luck.

And, as I posted here a long time ago, (and was dismissed outright), and as Sully just said before Congress, those with the talent, intelligence, drive, discipline and desire to fly commercially are taking a look at what has happened to the airline piloting profession and going elsewhere so they can make a living wage, and have a slightly better chance at a future and those that do come will be second tier, perhaps with aviation stars in their eyes. By the time the accident rate begins to climb again, all we'll hear is the kind of nonsense we're now hearing about the Turkish accident...it was the altimeter's fault. Bullshxt.

In order to lower costs, this industry is putting an entire generation in it's cockpits who will be unable to fly an airplane or think. Wait'll they get into the left seat and the cranky old crocks that keep us alive and not kicking tin are retired.

What cost savings"..

Along these lines it would seem too that the basic flying skills of TRI & TRE's would be lacking , Excerpts from the accident report (BEA France) involving the crash of D-AXLA

http://www.bea.aero/docspa/2008/d-la...la081127ea.pdf

Excerpts from the freshly released crash involving an Airbus A320 on Nov 27/2008 by french "BEA" (Bureau Enquètes Accidents) on a test flight after release following scheduled maintenance at the factory

Airbus A320 D-AXLA.
Crew:
1 instructor pilot, TRI, TRE (Germany)
1 Copilot (Germany)
1 Pilot (New Zealand)
3 Technical engeneers from New Zealand airlines
1 Technical engeneer from New zealand CAA

" The pilot from New Zealand described the actions to take to perform a check at low speed planned in the programme"

"At 15 h 45 min 44 s the maximum recorded values were: PITCH 57 degrees, ALTITUDE 3,800 ft.THE SPEED WAS BELOW 40 kt".

"the airplane BANKED TO THE RIGHT UP TO 97 degrees and its PITCH REACHED 42 degrees nose-down".


"A few seconds after the increase in the engine rpm, all the witnesses saw the airplane suddenly ADOPT A PITCH UP ATTITUDE that they estimated as being between 60 and 90 degrees. The majority of the witnesses saw the airplane disappear behind a cloud layer. The noise generated by the engines was still constant and regular".
The airplane reappeared after a few seconds with a very steep nose-down angle".

"During the descent, the airplane pitch seemed to increase and the airplane struck the surface of the sea. Some witnesses remember a very loud « throbbing » that they heard until the impact".

CREW:

Captain:

Type rating Examiner authorisation for A318/A319/A320/A321 (TRE) n°D-196 issued on 2 July 2003 and valid until 2 August 2009.

Qualification as instructor for type rating training on A318/A319/A320/A321 (TRI) valid until 18 September 2011.
Rating for Cat III precision approaches valid until 5 March 2009


"""The crew HAD NOT RECEIVED ANY SPECIFIC TRAINING for this type of flight.The Air New Zealand pilot had undertaken two simulator training sessions following the programme described in by the OFC document"".


This seeems also to indicate that a TRI, TRE should not be qualified to carry out flights on the backside (Slow Flight)of the flight envelope.

""""In addition, no documents detail the CONSTRAINTS to be imposed on these FLIGHTS or SKILLS required of the pilots"""""""".

..and that there is no requirement to have the training or the skills to face such situations...


""In the context of their agreement, Air New Zealand and XL Airways Germany had agreed on a programme of in-flight checks based on an Airbus programme used for flights intended for the delivery (acceptance) of a new airplane to a client.

THESE FLIGHTS ARE PERFORMED BY AIRBUS ACCEPTANCE PILOTS AND ENGINEERS".

Would again indicate No flight to be permormed by TRE and TRI on the backside of the flight envelope..

Quite appalling.... in this era of joysticks and glass cockpits, the very essence of stick and rudder basics are gone forever, the above makes me think that virtual sim checks may not be enough, somebody sometimes will need to fly the plane....thank god it's not very often...

[markkal]

I wanted to start a new thread but my comment has been redirected
and listed here!!!!

Although closely related to this thread it may not be in the flow of the discussion herein!!!
Sorry chaps!!!

[1 to go]

markal

As someone who has conducted many of these Airbus acceptance flights and also a JAA TRE, I completely agree with your observation about the lack of practice of basic flying skills by the current generation of airline pilots. Recently we have had 2 aircraft stall on the approach where basic flying discipline was ignored.
Airline training departments have a responsibility to ensure that those sitting in the flight deck have these flying skills. I observe pilots that are more concerned about what to say (SOPs) than what the aircraft is doing. I see much over briefing and not enough common sense.
With regard to the D AXLA accident I believe that there would not a have been a problem had the crew performed the low speed exercise as per the A320 flight acceptance schedule.

[alph2z]

.


Ouuuufffff,

This was a lot more work than I originally expected, but a great learning experience in digitizing, curve fitting, interpolation, plotting software, etc.....

The following graph is derived from only the DFDR data from the preliminary report, more specifically from the Altitude, CAS, and pitch vs time.

The data is really good except for Altitude. It seems that the altitude is not recorded at exactly every second, but instead at 2 rates, and does not seem to be corrected in the altitude data of the prelim report. This reveals itself more during the fast climbs and descents, e.g. in the last 20 secs. Does someone have any idea why this is ?

Therefore, a minimum of filtering was done to the altitude data. The worst affected is G normal. Others much less.

My main original intent was to try this experiment and to obtain the normal G acceleration near the end of the flight which is 1.3 G here. I believe that from the pitch change rate that this results in approx 3 G. I believe this method is usually used from a 1 G starting point. Anybody have and comments about the later method of obtaining G load ?
.

[recceguy]

This seeems also to indicate that a TRI, TRE should not be qualified to carry out flights on the backside (Slow Flight)of the flight envelope.
""""In addition, no documents detail the CONSTRAINTS to be imposed on these FLIGHTS or SKILLS required of the pilots"""""""".
..and that there is no requirement to have the training or the skills to face such situations...
""In the context of their agreement, Air New Zealand and XL Airways Germany had agreed on a programme of in-flight checks based on an Airbus programme used for flights intended for the delivery (acceptance) of a new airplane to a client.
THESE FLIGHTS ARE PERFORMED BY AIRBUS ACCEPTANCE PILOTS AND ENGINEERS".

OK, guys, let's write it in a clear manner. TRI/TRE, which are regarded as the highest positions in our industry, simply usually don't have the qualifications to perform those flights - which 90% of the airlines in various countries call "test flights", to look nicer and to make their pilots believe they are Test Pilots...
In some countries, you will never find this terminology - but instead check flights, acceptance flights, post-maintenance flights, and so on... does it look pedantic ? well, as much as pilots doing air displays when they have no training, or landing in bad visibility without the appropriate ratings...
The SETP (Society of Experimental Test Pilots) - an american body - specifically excludes membership from pilots who have been doing only maintenance flights...
A Test Pilot course, from one of the recognised schools in the world, takes about one year and half to complete - with grades, quoting and possible failure at the end of it, without getting the diploma - and usually candidates must already have an extensive background of flying, and be University graduates (not engineers please, Graduate Engineers if you prefer)

There has already been a semantic upgrade in Europe 10 years ago, with Acceptance Pilots becoming Test Pilots, and Test Pilots becoming Experimental Test Pilots - but not in any case in some countries would you allow autopilots operators, upgraded to SOPs and FMC instructors which is what TRI/TREs are to operate in flights with such unusual conditions as low speeds, extreme manoeuvres or configurations (well, extreme for the human material usually found in airlines cockpits)
That might sound as Top Gun ego, or territorial defence, with everybody laughing at it... well, until a story like the Perpignan one, with an aircraft in the water and the loss of all crew on board, doing things they should never have been doing (low speed part of the flight in a rush, halfway in the clouds, at the beginning of an IR procedure, and with 3000 to 2000 ft only below
and using a flight plan, area and associated ATC support unappropriate for the event.... yes, it's a job.
In a big company of my friends, one of the above-metioned TP schools has cheapened itself by coming and showing videos for two days about what their customers will call "test flying" What would you do for money... ? Test flying for dummies...
Please don't come back with the stories of A330 in Toulouse or BAC I-II in UK in the sixties, or other prototypes crashes in the history of real Test Flying - those were documented flights, with inherent part of risk accepted from the beginning by the crew and the industry...

[HarryMann]

Recceguy

A good point - the difference between proper test flying, from a manufacturer's persepctive...
and acceptance test flying.

A world of difference in approach to the job, as well as background engineering rigour, undertsanding and preparation.

[CONF iture]

Great effort alph2z !
But you know the BEA has all these data, but choose not to publish some of them ... !?

[Reinhardt]

Thank you recceguy, obviously some knowledge of the subject

Having seen myself the ridiculous boasting about those "flight tests" by some of our colleagues more proficient about SOP calls and FMC pages than with real aircraft handling, I can do nothing less than 100% agree with your point.
Maybe a dedicated company or government body to perform those acceptance flights should be the answer, rather than company pilots unfitted for the task ? (but then, who should pay ?)

[Gnd_Chk_Satis]

As a Lease Co Rep - who has done about 50 of these 'Demo Flights' - my thoughts go out to all these good guys - obviously they didn't intend for it to all end like it did....but these flights are potentially tough ...combination of post maintenance defects, non standard procedures, crew from two airlines & the Leasing co...and the time pressure to Return the Aircraft can cause problems. The time pressure is usually pretty severe given the money involved in these aircraft transfers...but needs to be removed from the actual flight scenario if at all possible.

Two main points I'd like to make are:

- a good complete and frank brief is essential - the written 'Demo Flight Schedule' needs to be very familiar to all parties and an 'Approved Demo Flight Schedule' at that - and possible scenarios (airspace, time or inop systems) discussed...safety is the primary concern - not the on-time Return of the Aircraft. The Demo Schedules are well thought out - and should normally be followed without deviation...we're not 'Test Pilots' - we're carrying out a routine Demo Flight - nothing more. Good systems knowledge is essential however.

- there can only be one Captain on the aircraft ...and it shouldn't be the Lease Rep (we usually sit in the jump seat) nor the new airlines Pilot (also usually on the Flight Deck) - but should be the Returning airline Capt - it is him and his FO who are working the Demo Flight Schedule and flying the aircraft. As the Leasing Rep or new airline pilot - our job is to observe only... and assist if requested - ie a good CRM environment. This needs to be discussed and made clear to all parties at the pre Flight Brief.

As the Leasing Rep I've always insisted on these two points...but I believe this is not always so.

As I say - tragic crash - and one which hopefully all of us will learn from. Thoughts are - as always - with the families.

Rgds
Gnd_Chk_Satis

[nixisfix]

Objection

Recceguy,

Even from the lofty heights of your test-pilot abilities you should be able to see that following the applicable "SOP" would have given the low-life autopilot operators enough altitude and time to get out of the system-failure induced stall. I am sure the "human material" deemed worthy of testing aircraft beyond normal limits follow a well thought out plan, the same as TRI/TRE's usually do on their "test-flights". Stray from the program and invite disaster, seems quite simple to me, but then again, I am not a test pilot...

[Pedro]

total agreement

I think 1 to Go is so perceptive in his post about lack of common sense, etc. But where are the corrective measures going to come from? The airlines? With their focus on the bottom line and training departments regurgitating airbus SOP's without looking at the wider picture.
Surely it is the pilot body, the Profession or what's left of it, to stand up and be heard. To tell industry what has to be done and the standards to be aimed for.

[scarebus03]

I have been involved extensively in these redelivery test flights over the last number of years and I seriously question with modern aircraft how useful they actually are. Most aircraft coming out of routine base maintenance do not have any test flights and when they do these test flights do not involve testing the flight recovery envelope, instead they have a normal flight profile which pretty much covers everything.

Why do we have to check 'last chance' systems on redeliveries which can adequately be checked on the ground given the proper training and tooling as part of more extensive ground checks after the maintenance check and/or painting?


I believe the ground/flight test schedule should be modified to ensure that all of the critical systems are checked on the ground after the maintenance/redelivery check/painting rather than in the air. The ground test schedule can be modified to ensure that these checks are included.

The majority of pilots that I have flown with on these flights had a lot of flying experience but no significant training in maintenance test flights or redelivery test flights.

Brgds SB03

[SawThe Light]

Agree with s/bus03. What was likely to be revealed on a low speed test that the last T/O or landing hadn't shown, other than the skill or perhaps lack of skill of the PF.


STL

[exeng]

scarebus03

Very good point made. It would seem that Pilots put in the frame for these 'test' flights are not actually fully qualified to fly them, nor are the flights actually necessary.


Regards
Exeng

[lomapaseo]

nor are the flights actually necessary

I'm afraid that we are missing both sides of this argument. They are obviously necessary to the side that ordered them. So what is their side of the argument?

[Huck]

I've found quite a few things on these flights that made it past the ground checks.

You can't simulate air loads, or the changing geometry of the airframe, or g's.

I guess the worst I found was the CF-6 that wouldn't start inflight. Had lost a few compressor rows - but not the ones normally borescoped. The only clue - it would start on the ground but not in flight.

I've found a dump valve that stuck open. Imagine that - lose an engine, dump to landing weight (MD11), then the fuel automatics start shifting fuel to correct the imbalance and you start dumping again....

We had an APU that would not start inflight, but was fine on the ground. After SIX reflies they found an arc in the ignition circuit - the flexing of the airframe in flight caused it.

I've found two ADG's (RAT's) that did not work. They had both been spin-tested on the ground.

I guess the best point I can make is this: my company would absolutely not do these test flights if they didn't have to. They save us money, in other words.

[doubleu-anker]

1 to go

Totally agree with your observation of the new generation of "systems operators". Auto throttles have a lot to answer for.

recce guy

Excellent post and fully agree.


"Line pilots" try to stay out of trouble.

Tests pilots look for trouble. Test/acceptance flying, invites trouble.

If you look for trouble long enough, trouble will visit you.