Some prelim. surmising. Weather and wind not a causal factor. Crew incapacitation unlikely. Runaway stabiliser trim unlikely. Large loss of engine thrust highly likely. If fuel tanks were near empty, investigators will already know this. They will also know what engine parameters were during final approach and on impact. They will also know (assuming CVR was operating) what pilots were saying to each other.
It looks horribly like pilot(s) were tempted to attempt to extend/stretch glide to reach threshold. For whatever reason, the airspeed was allowed to decay as nose rose and aircraft reached its stall angle-of-attack. It then fell out of sky until tail impacted which caused forward fuselage to slam down with accelerated very high G forces possibly causing severe trauma to spine/neck of pilots and those pax. seated in front section. Possibly ruptured aorta.
As to why two professional pilots would permit airspeed to reduce to such a perilous state at very low altitude is very difficult to comprehend. I feel that "human factor" aspect may well be the major focus of the investigation process. The first thing most/all of us had drummed into our heads was: "maintain thy airspeed!" Like, hold the nose down to store sufficient energy to enable a flare to absorb the impact forces ALONG the ground...not INTO the ground.
Blame the dead pilots you say? That's been done before many times to deflect the blame from where it is due. What is your agenda?
Do you recall ever, a muslim being able to say that their pilot/pilots did any thing wrong?
never! it is allways the aircraft or somebody else.
so some one sitting in istanbul or ankara who has no other facts then the those we all see, goes out to the public and say that he has the answer.
b.t.w, I have 10 years on the 737NG , many landings in AMS. 2 minutes diff between aircrafts is STD, all over europe and the globe, never had an issue that ended up violently. also, the reported wind is 210/11 that means 30 deg from the R side, pushing the turb to the left thus reducing the overall effect.
see also the reaction of local officials in the egypt air crash on the 767 flight from the US to CAI. they are still saying that the 767 elevetor is to blame.
over here it looks like a power loss from some reason.
there where some cases of fuel leak on 737NG.
the combination of luch of power, intact fan blades, low airspeed, leads somewhere..
I'd appreciate it if we could keep religion out this please folks.
I for one will be waiting for an official investigation before commenting upon on any possible causes.
My wings are like a shield of steel.
would like to make my two points here.
first, yes, in turkey many muslims blamed the pilots, and many other muslims did not blame them, pertaining to this accident situation. secondly, yes, eastern people may react differently to everything, but here should not be the place to underline that opinion.
what i said related to the publication of the turkish pilot association.
they without any official evidence, already decided what have happend in this case.
besides that, i totaly agree that we should wait for the facts.
having the chance to meet a lot of muslim pilots, on different ocasions, I have all the respect for them.
I hope you are right, eagle driver. Tomorrow we should know more.
Indeed. it looks as we already have some info. according to the last release the plane was "high and fast" on the approach and ended up stalling all to the ground.
this is a classic "UNSTABlIZED APPROACH" that in all modern airlines as well as BOEING it is mandatory to execute
a missed approach by the time you reach 1000' [or 500' in some cases].
to add to all these, the PIC [pilot in command - captain] was bussy with giving the F/O a lesson regarding the landing checklist.
doing that on such a critical faze of the flight while your plane is about to stall dose not present the proper way to command and fly your plane.
this si also a poor practice of CRM [crew resorce managment].
too bad so many people had to pay the price for that
Boeing bulletin on the crash:
The US NTSB, FAA, Boeing, the Turkish DGCA, the
operator, the UK AAIB, and the French BEA continue to actively support
the Dutch Safety Board's (DSB) investigation of this accident.
The DSB has released a statement on the progress of the investigation
and has approved the release of the following information.
While the complex investigation is just beginning, certain facts have
emerged from work completed thus far:
- To date, no evidence has been found of bird strike, engine or
airframe icing, wake turbulence or windshear.
- There was adequate fuel on board the airplane during the entire
- Both engines responded normally to throttle inputs during the entire
- The airplane responded normally to flight control inputs throughout
The Digital Flight Data Recorder (DFDR) data indicates that the crew
was using autopilot B and the autothrottle for an ILS (Instrument
Landing System) approach to runway 18R at Amsterdam Schiphol airport.
During the approach, the right Low Range Radio Altimeter (LRRA) was
providing accurate data and the left LRRA was providing an erroneous
reading of -7 to -8 feet. When descending through approximately 2000
feet the autothrottle, which uses the left radio altimeter data,
transitioned to landing flare mode and retarded the throttles to the
idle stop. The throttles remained at the idle stop for approximately
100 seconds during which time the airspeed decreased to approximately
40 knots below the selected approach speed.
The two LRRA systems provide height above ground readings to several
aircraft systems including the instrument displays, autothrottle,
autopilots and configuration/ground proximity warning. If one LRRA
provides erroneous altitude readings, typical flight deck effects,
which require flight crew intervention whether or not accompanied by an
LRRA fault flag, include:
- Large differences between displayed radio altitudes, including radio
altitude readings of -8 feet in flight.
- Inability to engage both autopilots in dual channel APP (Approach)
- Unexpected removal of the Flight Director Command Bars during
- Unexpected Configuration Warnings during approach, go-around and
initial climb after takeoff
- Premature FMA (Flight Mode Annunciation) indicating autothrottle
RETARD mode during approach phase with the airplane above 27 feet AGL.
There will also be corresponding throttle movement towards the idle
stop. Additionally, the FMA will continue to indicate RETARD after the
throttles have reached the idle stop
Boeing Recommended Action
- Boeing recommends operators inform flight crews of the above
investigation details and the DSB interim report when it is released.
In addition, crews should be reminded to carefully monitor primary
flight instruments (airspeed, attitude etc.) and the FMA for autoflight
modes. More information can be found in the Boeing 737 Flight Crew
Training Manual and Flight Crew Operations Manual.
Operators who experience any of the flight deck effects described above
should consult the troubleshooting instructions contained in the 737
Airplane Maintenance Manual. Further, 737-NG operators may wish to
review 737NG-FTD-34-09001 which provides information specific for the
737-NG installation. Initial investigations suggest that a similar
sequence of events and flight deck indications are theoretically
possible on the 737-100/-200/-300/-400/-500. Consequently the above
recommendations also apply to earlier 737 models.
AirSpace - more than just hot air
OK so there was a technical fault , one which should have been picked up and handled by the crew . The Boeing Bulletin says it all . I don't think the crew are off the hook here. No doubt much more investigation is needed , but the approach should have been monitored and the decay in airspeed and other discrepencies picked up.
Flightglobal: Investigators of the Turkish Boeing 737-800 approach crash at Amsterdam have found that a sudden reduction in engine thrust coincided with a step-change......Author: David Kaminski-MorrowDate: 04 March 2009Read the full article
Author: David Kaminski-Morrow
Date: 04 March 2009
Read the full article
Wouldn't such a large difference between the two radio altimeter readings cause a fault that would kick off the autopilot? Is there also a software glitch here? It doesn't seem correct that the autothrottle would accept data from only one altimeter where there are two. I thought that is why there are redundant altimeters - to prevent exactly what happened should one fail. To make matters worse, there were also barametric altimeters, albeit less accurate, which also would tend to dismiss the left side altimeter as being incorrect....
I'm very surprised to read that the radio-altimeter has authorithy to retard thrust to idle on the B737, even the NG's.
I'm not familiar with the aircraft type, but I'm familiar with Boeing's "soft automation" philosophy.
Even on brand-B's aircraft, the automation would voice "retard" but the action would still be the pilot's authorithy.
Are all these articles not jump-starting a more thorough analysis of available DFDR data ?
Could someone enlighten me about the B737 NG autothrottle logics ?
the "soft automation" does not replace the basic actions of the auto pilot sys.
so, during auto pilot approch both a/p + auto throttle are engaged in order to alow autoland [fog..]
this includes full autopilot/autothrottle landing. in the 737ng [as well as other B models] the auto pilot will start the flare
at 45 feet [RA] and the autothrottle will retard. the auto sys use RA [radio alt] info in order to start these events.
a malfunction of this kind [one RA sends wrong data] may couse the sys to freek out in a way that may not be predicted.
in most cases the left sys is the master [due to the side of the captain].
yet, cerfull monitoring systems perfomence and on-time intervention is one of the basics of modern civil A/C operations.
so, even if the system goes wrong and do funny stuff, flying almost 2 minutes in idle thrust during final and in landing configuration, letting the speed to reduce to some 95K [instad of around 135K av] and letting the A/C drop far below
the GS all the way to 400' without the captain doing anything before the stickshaker activets leaves a very bad impresion
regarding crew performance. they seem to neglect the very basic of flight..
too bad and too sad.
Thanks Eagle Driver for the brief.
Pending the investigation interim and final reports, this event leaves me with mixed feelings about the respective roles of "system HF" and ... "human HF".
It is wise to wait and see what the reports will teach us.
In the meantime, further enhancing PF / PNF monitoring skills may be a wise course of action.
Sometimes, as I reflect back on my airline flying years and, later accident investigation and airline QA and flight ops. management periods, I wonder, after such strange events as this, whether I am still living in the real world? So a radio-altimeter unit malfunctions...so what! Everything malfunctions sooner or later. Autoland systems have been around for yonks. The crew, as far as I know, still had the pressure altimeter readouts, the ILS glide-slope indications, GPS/DME information, attitude indicators, airspeed indications and they knew, just prior to the RA failure, that they were several miles out at an appropriate altitude. (mind you...I am assuming that). I have not flown the particular type, but certification rules insist that there must be multi ways to gain manual control of power levers and flight controls. Did all of those also fail? Even if all the altitude indicators failed, or provided conflicting data, one has only to dump cabin pressure to use the cabin-altitude indicator to obtain an approx. altitude reading....certainly good enough for their spatial location; wouldn't you think? I am not denigrating the Captain or his F/O. Something else must have been going on in that cockpit which caused the pilots not to get rid of the autopilot and just fly a perfectly simple ILS approach in quite benign flight conditions. Something bizarre must have occurred to prevent the experienced profressional pilots from, as the airspeed and height decayed alarmingly, from executing the quite simple actions which every student pilot has drummed into them from almost day one of their training....increase thrust and reduce angle-of-attack....and DO IT NOW! It is fundemental and, in my opinion, really does not require a lengthy CRM style discussion. Just keep it flying and have a meeting about it later. And don't I recall from my instructing years something about Selective Radial Scan! And that Power + Attitude = Performance?
This ghastly crash appears to be so bizarre that it does not seem possible that it could be the fault of the pilots.
The crew may not be completely blameless, but they are damn near blameless. It looks like Boeing gets at least 95% of the blame here. Their all operators message was a tragic joke--it was as if the lawyers had written it to cover Boeing's guilty "***." What the hey is the "if you see this error, read through this manual, then that manual, then another manual, then page to the troubleshooting section." That places blame squarely from the pilots and on Boeing as there obviously was no time to read one page of the first recommended manual before they were doomed to crash. That the airplane didn't act as it was designed to with altimeters that disagreed also points to a manufacturing and/or maintenace defect--manufacturing I would guess, as the airplane was fairly new. If you saw the "leaned out" (leaned out of any inspection processes that is) factories at Boeing like I did (as I worked on the worst of them) then you would understand why so many manufacturing defects get delivered to airlines by Boeing. With no visibility it was impossible for the crew to know which altimeter was wrong. I suppose these units read -X feet often just before touchdown. It appears that the pilots thought touchdown of the wheels was imminent, and they did not believe they were at 1950 feet as the working (in hindsight) altimeter read. Autopilot selection was mandatory due to lack of visibility. Therefore, any blaming of the pilots is completely irrational. That the autopilot could be slaved to a bad altimeter that caused the doomed flight path is almost criminally negligent on Boeing engineering's part. That they didn't see this and write the flight manual accordingly is the same. Must have been a focus on cost and schedule instead of safety when it was developed. To err is human, but in such critical jobs, processes should be in place to eliminate human error. Why so many otherwise knowledgeable people knee jerk at blaming the pilots despite the noted evidence they are not at blame I do not understand, unless they work for Boeing, or are afraid what Boeing will do to them if Boeing finds out they didn't cover for their blame.
Blaming the crew is NEVER the correct response!
... and although lately Boeing seams to be a bit behind the power curve, everybody must admit that Boeing knows how to build planes!
On the other side of the coin, TK SOPs must include a double altimeter check during the app (i.e. at the OM) and a xcheck with the RA especially if you are shooting a C2 or C3 app!
About this crash what do you people think of the following ideas.
To make it more useful to work at Sea, Snow, River, Ice, Canal, Water by installing FLOATS & SKIDS under it along with or without landing gears or 4 installation in the mean time and its engines should be modified by their EDP to build pressure to refuel a/c & helicopters flying under or below it or around 360 degress around it . Thanks & RegardsHussain Asif JafriAviation StudentB.556/13 Gulberg 75950 F.B. Area KHI Pakistan009221-03002385768Aviation Tech Services Training SchoolClass 5A Student Since Aug 2003 for the certificatethree years course of Aerospace engineering.009221-0216022035Schon Flying School Engineering Hanger on OJT For 6Weeks From ATS.
Like csverv says - click off the damn autopilot and fly the jet - don't let the darn thing fly you - even with all the technology that the new planes have - there still is a disconnect button for any pilot to fly it like it was an analog!! Take command, don't let it fly you!
Fly the plane Dudes!!
that's the reason why we love our job! Fly the plane!
that's the reason why we still have a future in airline transport world! Fly the palne!
Passengers and Company holder want a pilot in front of a big jet and not a computer! Fly the plane!
to infinity and beyond!