Turkish Airlines cargo 747 crashes in Kyrgyzstan [Archive]

Ganzic

16th Jan 2017, 05:48

Looks like the rescue operation is pretty much still ongoing. It looks like they crashed past the rwy on the north side, https://www.google.co.uk/maps/place/Дачи+СУ,+Kyrgyzstan/@43.0619512,74.4438969,3820m/data=!3m1!1e3!4m5!3m4!1s0x389ee858f08d637d:0x96d689041daa113 f!8m2!3d43.0640371!4d74.4364417

SA 16/01/2017 06:30->
METAR COR UCFM 160630Z VRB01MPS 0500 R26/0550N FZFG VV002
M08/M09 Q1022 R26/19//60 NOSIG=
SA 16/01/2017 06:00->
METAR UCFM 160600Z VRB01MPS 0350 R26/0400N FZFG VV001 M08/M10
Q1023 R26/19//60 NOSIG=
SA 16/01/2017 05:30->
METAR UCFM 160530Z 00000MPS 0250 R26/0300N FZFG VV001 M08/M09
Q1023 R26/19//60 NOSIG=
SA 16/01/2017 05:00->
METAR UCFM 160500Z 00000MPS 0200 R26/0250N FZFG VV001 M08/M09
Q1023 R26/19//60 NOSIG=
SA 16/01/2017 04:30->
METAR UCFM 160430Z 00000MPS 0150 R26/0200N FZFG VV001 M09/M10
Q1023 R26/19//60 NOSIG=
SA 16/01/2017 04:00->
METAR UCFM 160400Z VRB01MPS 0150 R26/0175N FZFG VV001 M09/M10
Q1024 R26/19//60 NOSIG=
SA 16/01/2017 03:30->
METAR UCFM 160330Z VRB01MPS 0100 R26/0150N FZFG VV001 M09/M10
Q1024 R26/19//60 NOSIG=
SA 16/01/2017 03:00->
METAR UCFM 160300Z VRB01MPS 0100 R26/0150N FZFG VV001 M09/M10
Q1024 R26/19//60 NOSIG=
SA 16/01/2017 02:30->
METAR UCFM 160230Z VRB01MPS 0100 R26/0250N FZFG VV001 M09/M10
Q1024 R26/19//60 NOSIG=
SA 16/01/2017 02:00->
METAR UCFM 160200Z VRB01MPS 0150 R26/0375N FZFG VV001 M09/M11
Q1024 R26/19//60 TEMPO 0100 FZFG=

Wx in that region in winter has taken many lives in the past. Although it looks right on the numbers for CAT2 ILS RW26.

Airbubba

16th Jan 2017, 06:08

Well from the pictures it would have a been a hell of an overrun... But at this stage I guess anything is possible.

The data on FR24 looks pretty solid to me. I don't think those houses were on the runway and the village they hit is indeed west of the airport.

A decelerating descent on the glide is depicted but the groundspeed seems high with the last data point at 162 knots at 0116Z. This seems to correlate with the last point on the FlightAware plot giving 165 knots a few seconds earlier:

Flight Track Log THY6491 16-Jan-2017 HKG / VHHH - FRU / UCFM FlightAware (http://flightaware.com/live/flight/THY6491/history/20170115/1710Z/VHHH/UCFM/tracklog)

DaveReidUK

16th Jan 2017, 06:51

The data on FR24 looks pretty solid to me. I don't think those houses were on the runway and the village they hit is indeed west of the airport.

A decelerating descent on the glide is depicted but the groundspeed seems high with the last data point at 162 knots at 0116Z. This seems to correlate with the last point on the FlightAware plot giving 165 knots a few seconds earlier:

Though at the 162 kt point they still had about half of Bishkek's 14,000 ft/4,200 m runway ahead of them, and were around 3,000 m from the nearest habitation.

Clearly there's more to the story than is apparent from the FR24/FlightAware data.

Capt Groper

16th Jan 2017, 07:03

Flight tracking data, if correct, indicates A/C platformed at 3100', Jep chart states 3400'.
M09 ~ 10% diff ~= 300'
Just an observation of the published data.

exynos

16th Jan 2017, 07:20

M09 ~ 10% diff ~= 300'

Could you please explain this?
Regards.

Kulverstukas

16th Jan 2017, 07:34

qwKZdWMgVUY

WOrnaiIKM88

Local authorities said that it overfly RWY, then hit the fence and crashed at the houses. Also was said that pilot managed to get out but died on the way to hospital. Death toll now is about 31 and nine body parts found...

Akrep

16th Jan 2017, 07:36

Could you please explain this?
Regards.

Cold weather correction for altitude

Rule of thumb -10c add 10% altitude to your altimeter for your real altitude.
In short in cold weather your indicated altitude is always higher then you really are.

golfyankeesierra

16th Jan 2017, 07:39

In short in cold weather your indicated altitude is always lower then you really are
You mean the other way around!! :uhoh:

Your true altitude (height) is lower then the indicated.
Remember: cold=dangerous

DaveReidUK

16th Jan 2017, 08:01

aRGpJ6A3jTE

bekolblockage

16th Jan 2017, 08:02

Flight tracking data, if correct, indicates A/C platformed at 3100', Jep chart states 3400'.

FR24 will be showing uncorrected Mode C data. (encoded alt based on 1013)

QNH was 1023/1024 according to the METARs.
30 ft/HPa
So 300 ft sounds about right.

Capt Groper

16th Jan 2017, 08:16

Could you please explain this?
Regards.

http://http://code7700.com/altimeter_temperature_correction.html

Review first image for picturial explanation.

However this platform ALT diff has now been explained by the previous post by bekolblockage. FlightAware altitude data is based on 1013mb.

jackcarls0n

16th Jan 2017, 08:52

How is Cold Weather Altitude Correction going to make any difference on an ILS CAT II approach? Altitude correction would be done for FAF, MAA, DA and MSA!

Kulverstukas

16th Jan 2017, 09:08

Captain İbrahim Gurcan Dirancı, FO Kazım Öndül
Loading masters Melih Aslan and Ihsan Koca.

Deepinsider

16th Jan 2017, 09:30

Let's all please hope this is not yet another botched go-around.
Autopilots don't botch them, human pilots can though. Watch
what unfolds as they investigate.
In the meantime, terrible horror for a lovely village.

A320baby

16th Jan 2017, 09:34

I don't think it's a good idea to post the names of the crew

Prada

16th Jan 2017, 09:36

Drone video puts the end of debris area here https://www.google.com/maps/place/43%C2%B003'23.7%22N+74%C2%B026'04.7%22E/@43.056581,74.4338532,294m/data=!3m2!1e3!4b1!4m5!3m4!1s0x0:0x0!8m2!3d43.056581!4d74.434 629

This place is visible in Drone video @ https://youtu.be/qwKZdWMgVUY?t=2m28s

Kulverstukas

16th Jan 2017, 09:53

http://avherald.com/img/mycargo_b744_tc-mcl_bishkek_170116_3.jpg

Hotel Tango

16th Jan 2017, 09:58

I don't think it's a good idea to post the names of the crew

No problem if it's already released in the public domain. You have to remember that many countries, especially in that part of the world, have different cultures to ours.

Kulverstukas

16th Jan 2017, 10:04

It's already released in Turkish media. It's also stressed that FO was retired forces pilot, served till 2009 in Afghanistan.

Sam Asama

16th Jan 2017, 10:11

Kulverstukas: Thanks (as usual) for your contributions already to this thread.

Kulverstukas

16th Jan 2017, 10:13

thf

16th Jan 2017, 10:58

Let's all please hope this is not yet another botched go-around.

Aviation Herald (http://avherald.com/h?article=4a38d07d&opt=0):

(...) was on final approach to Bishkek's runway 26 at 07:18L (01:18z) when the aircraft went around from very low height but did not climb out to safety, impacted terrain about 1100 meters/3600 feet past the runway end and went through a couple of houses of a village.

dfstrottersfan

16th Jan 2017, 13:13

Quote:
Flight tracking data, if correct, indicates A/C platformed at 3100', Jep chart states 3400'.
FR24 will be showing uncorrected Mode C data. (encoded alt based on 1013)

QNH was 1023/1024 according to the METARs.
30 ft/HPa
So 300 ft sounds about right.

Very often FR24 lands you on a parallel non existent runway or hundreds of meters after or before

DaveReidUK

16th Jan 2017, 13:16

Very often FR24 lands you on a parallel non existent runway or hundreds of meters after or before

Only for a small minority of aircraft that don't have GPS-powered ADS-B.

Not relevant here.

Nemrytter

16th Jan 2017, 13:23

FR24 is notoriously unreliable, attempting to investigate what happened based upon data that (in many cases) is extrapolated or interpolated is just silly.

Kulverstukas

16th Jan 2017, 14:02

One of three recorders found.

Ex Cargo Clown

16th Jan 2017, 14:13

As much fun as FR24 is to play with, it's far from perfect. For instance, I've just had an A320 land in my back garden :o

dfstrottersfan

16th Jan 2017, 14:35

Only for a small minority of aircraft that don't have GPS-powered ADS-B.

Not relevant here.
Just commenting that FR24 is not accurate and relies on interpolation -

aviator17

16th Jan 2017, 14:49

How is Cold Weather Altitude Correction going to make any difference on an ILS CAT II approach? Altitude correction would be done for FAF, MAA, DA and MSA!
Exactly you are right!

Magplug

16th Jan 2017, 15:11

Parallels are being drawn here with the recent botched 777 go-around at DXB....

I do have my doubts. The Cat II minima for FRU26 in my docs says 350M RVR and RA99'. At the point of deciding to GA and announcing 'Go-Around Flaps 20' the aircraft should have been in a perfect position to land and just short of threshold. The DXB issue of the Boeing TOGA mode becoming unavailable is only after touchdown so that issue should not come into play here.

If however the suggestion is that this aircraft did GA from minima without applying any power then it seems to have flown an unbelievably long distance (4000m runway plus another ~2000m upwind) before it stalled into the ground. I simply don't buy the idea.

There is another possibility - The NGFMC in the 744 generates the characteristic speeds when VNAV selected on the GA... It is also unbelievably unreliable being prone to failures giving inappropriate speed generation and/or complete loss of Autothrottle/VNAV/LNAV functions. Not at all what a tired crew needs going round from a Cat II approach with ****ty weather on minimums.

pax britanica

16th Jan 2017, 15:19

lomapaseo

16th Jan 2017, 15:29

Is it something to do with freight operations-less experienced less capable crew ?? Less well maintained aircraft, greater crew fatigue ?

Read the accident reports and get back to us with a more specific question

ulugbek-pilot

16th Jan 2017, 15:31

Go around, cargo shift. Possible?

GlueBall

16th Jan 2017, 15:34

"The TC-MCL registered, BOEING 747-400 typed aircraft owned by our company, was on her route from HONG KONG to BISHKEK when it crashed over Kyrgyz airspace approaching BISHKEK-Manas Airport on January 16, 2017 at 1:20 GMT time (4:20 am Turkish time)

"We are very sorry to announce that Captain Pilot Ibrahim Gürcan DIRANCI, Co-Pilot Kazim ÖNDÜL, Load Master Melih ASLAN and Flight Technician Ihsan KOCA passed away in this sad incident. Due to the fact that the aircraft crashed into the edge of a residential area, 33 civil people passed away along our 4 crew members, according to the first information we received. We want to express our deepest thoughts and condolences to the families of our crew members and the Kyrgyz people.

"There is no clear and confirmed information about the reasons for the incident yet. Our Company has commissioned two captain pilots at Manas Airport to investigate the accident together with authorities. Furthermore, our technic staff is on their way to the site. Also the investigation has started by both, Kyrgyz and Turkish Ministries of Transport and Communication and the General Directorate of Civil Aviation.

"We are in constant contact with the Ministry of Transport and General Directorate of Civil Aviation, Turkish Embassy in Bishkek-Kyrgyzstan, Airport Authority and Kyrgyzstan Civil Aviation Authority. Clear and confirmed information about the accident will be shared with the public when available.

"The flight with the cargo from Hong Kong to Bishkek-Istanbul was airborne as planned, after all the checks were carried out, and was on her way approaching Bishkek Airport without encountering any setback or problems during the flight.

"The crew rested for 69 hours in Hong Kong before the related flight and checked out for the flight to complete the 6-hour flight from Hong Kong to Bishkek. The airplane was lifted with a planned total of 85,618 kg "general cargo" load safely. There are no faults recorded in the technical log book of the aircraft.

"The crashed aircraft is a B747-400 freighter, manufactured in 2003 and with a cargo capacity of 116.462 kg. As of December 10, 2015, she was in the fleet of ACT Airlines. Maintenance of the related aircraft was carried on in timely manner and according to the aviation standards like the other aircrafts in our fleet.

"Our team which we lost were experienced and specialised flight crew that has carried out their professions with great success for many years. Captain İbrahim Gürcan DİRANCI and First Officer Kazım ÖNDÜL are ex-military pilots who have represented Turkish Air Force for many years abroad. Our Captain has a total of 10,821 flight hours of which 833 hours are on B744. Our First Officer has a total of 5910 flight hours of which 1771 hours are on B744.

"Our Load Master Melih ASLAN from the flight crew has been working in our Company since 2007 with vocational training and competence of total of 14 years of Load Master experience. Our Flight Technician Ihsan KOCA has served as a technician in the Turkish Air Forces for many years and has been serving in our Company since 2006.

"According to the first findings, it is understood that the reason of the related accident is not caused by technical reasons or loading related factors. The actual reason of the accident will be shared with the public after the inspection of aircraft and the place where the accident happened.

"All losses including life and property occurred in the accident is under coverage of insurance.

"Because of the accident, as ACT Airlines, once again we condole with the mourning people that lost their relatives, Kyrgyz people and Turkish Civil Aviation; and we sincerely share their grief."

ACT AIRLINES INC.

750XL

16th Jan 2017, 15:39

Itsa question i have raised before but there have been a lot of 747F crashes compared to the vastly more numerous pax versions. Is it something to do with freight operations-less experienced less capable crew ?? Less well maintained aircraft, greater crew fatigue ?

The last few 74F losses:

National Airlines Flight 102 (https://en.wikipedia.org/wiki/National_Airlines_Flight_102) = load shift

Asiana Airlines Flight 991 (https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_991) = hold fire

UPS Airlines Flight 6 (https://en.wikipedia.org/wiki/UPS_Airlines_Flight_6) = hold fire

Icelanta

16th Jan 2017, 15:51

What happens if you get no retard from the AFDS at 25ft...

Indeed, the aircraft will keep on flying happily a few feet along the runway, in ground effect, with Vref.

I do not want to speculate though.

Flightmech

16th Jan 2017, 15:59

According to the first findings, it is understood that the reason of the related accident is not caused by technical reasons or loading related factors. The actual reason of the accident will be shared with the public after the inspection of aircraft and the place where the accident happened.

Little early to be confirming this?

Kulverstukas

16th Jan 2017, 16:20

Little early to be confirming this?They lifted one recorder. Probably they read it already?

Airbubba

16th Jan 2017, 16:40

https://cdn.aviaforum.ru/images/2017/01/821824_ab5ff288b7ce43b14b732ec7029cc667.jpg

From another point.

And looks like its not airfield fence but NDB/VOR fence:

https://yandex.ru/maps/-/CZXgqQK9
or https://goo.gl/maps/QamxfrwGNDC2

Shoot from North to SE direction

Kulverstukas: Thanks (as usual) for your contributions already to this thread.

Yes, thanks once again for your insight in this area. The vertical yagi antenna next to the striped building looks to me like a 75 MHz marker beacon antenna which would normally be on the extended runway centerline.

Looks like the FR24 data is accurate, they were indeed lined up on the runway 26 and went past the end sometime after the last data point was transmitted.

Very often FR24 lands you on a parallel non existent runway or hundreds of meters after or before

Only for a small minority of aircraft that don't have GPS-powered ADS-B.

Not relevant here.

I agree with Dave. This data doesn't seem to be MLAT or interpolated in the minutes prior to the mishap. FR24 and FlightAware use separate networks although some folks (don't ask me how I know ;)) simultaneously feed data to both.

747-400 is quite a capable aircraft. Something must have gone horribly wrong for a crash to happen. They would have most probably planned on an auto land for the weather condition at the time. And if autoland wasn't working, then the minimums would be for a CAT 1 approach, the weather is well below CAT 1. But that depends on the company's SOP. I wonder if icing had a role to play. The runway is pretty long to land without speed brakes working. Something didn't go well and they performed a go-around?

There is another possibility - The NGFMC in the 744 generates the characteristic speeds when VNAV selected on the GA... It is also unbelievably unreliable being prone to failures giving inappropriate speed generation and/or complete loss of Autothrottle/VNAV/LNAV functions. Not at all what a tired crew needs going round from a Cat II approach with ****ty weather on minimums.

With that weather, I would expect a fully coupled approach and an automated go around which is normally not a difficult maneuver. However, I've had the automation kick off just as the power came up on a coupled go around and there are definitely a few seconds of recognition time, especially if other warnings are present at the same time.

Widebody freighters do seem to crash much more often than widebody airliners in the past couple of decades. Whether the standards for pax and cargo flying should be the same has long been hotly debated here and elsewhere.

The high groundspeed rapidly bleeding off on final in the ADS-B data may indicate a decreasing tailwind or perhaps a late configuration with the power back trying to slow down. We will know more in a year or two when the report comes out.

Airbubba

16th Jan 2017, 17:03

FR24 was able to recover additional ADS-B position data that leads to the crash site on the corner of the nearby village:

Initial ADS-B data recorded the aircraft at 43.061371, 74.478104 and 2,375 ft AMSL at 01:16:39 UTC. Efforts to decode additional data resulted in an further 38 seconds of ADS-B data. In this data, the last recorded position of the aircraft is 43.056816, 74.440155, 2350 ft AMSL at 01:17:16.5 UTC.

See: https://www.flightradar24.com/blog/crash-of-mycargoact-airlines-flight-tk6491-and-additional-ads-b-data/

b1lanc

16th Jan 2017, 17:35

Capt had only 833 hours in type? A bit light?

PJ2

16th Jan 2017, 17:36

Airbubba;

I am by no means a believer and accepter of FR24 data for the purposes of accurate, reliable investigative processes such as we see here and in other events. I've taken a look at the linked ADS-B page, 2nd image:

https://photos.smugmug.com/photos/i-b9nbkDR/0/L/i-b9nbkDR-L.jpg

...and I'm wondering, if the airplane was actually on the ILS, why does ADS-B data show it so high - or is FR24 data not accurate in altitude?

In any case, I remain unconvinced that it's a useful tool for finding out what happened and I suspect those that do actual investigative work including the interpretation of the recorders, will concur.

West Coast

16th Jan 2017, 17:40

Widebody freighters do seem to crash much more often than widebody airliners in the past couple of decades. Whether the standards for pax and cargo flying should be the same has long been hotly debated here and elsewhere.

If hamstrung by pax carrying hazmat and other riskier cargo restrictions, there'd likely not be a cargo company around beyond those carrying flowers from South America. An over exaggeration of course but given the nature of the business, cargo outfits won't achieve parity with the safety record of pax carrying airlines when looked at in totality.

douglas744

16th Jan 2017, 18:06

B744 Go around procedure :

" Go Around "
TOGA,Flap 20
+ CLIMB, Gear up
400', LNAV or HDG Sel
3000' ( or less depending on your SOP ), VNAV or FLCH set speed
Follow missed approach procedure for that runway
Auto pilot can be reengaged in stable conditions.

Problem 1

Normal pitch for go around on 4 engines is about 12.5 degrees ( 3 engines,10 degrees )
If the pitch is insufficient , aircraft may continue to sink and impact will follow .

Problem 2

If asymmetric condition occurs during the go around and not fully countered by rudder,
A/C will roll over and your time to impact is measured in seconds.
Also, if the autopilot was maintained prior to the go around, a failed engine still needs rudder application due to the AP kicking off.

Problem 3

If TOGA mode fails, a No-TOGA go around must be done. This needs practice and plenty of training.

Problem 4

Regardless of the altimeter setting, the GPWS would have alerted the crew with a " TOO LOW, Terrain " or other warning and this requires immediate MAX THRUST setting combined with 20 degree initial pitch up or even more ( PITCH LIMIT ANGLE ) reaction from the pilot and a check that the speed brakes are in .

The list goes on...

The key here is PILOT TRAINING ,COMPANY PROCEDURES, Crew CRM !
Far from blaiming anyone at this point, one can see all the trappings of a go around under
adverse weather conditions , Heavy landing weight, high elevation if unprepared.

The 747 is a dandy to fly but can be a handful with high controls loading if out of trim and poor thrust/ pitch management.

Airbubba

16th Jan 2017, 18:15

Airbubba;

...and I'm wondering, if the airplane was actually on the ILS, why does ADS-B data show it so high - or is FR24 data not accurate in altitude?

The altitude is normally uncorrected barometric data from what I've seen although I've heard it claimed that it can be geometric GPS altitude. Some ADS-B viewing software, e.g. RadarBox, lets you set a transition altitude/level and enter an altimeter setting but I don't think the standard FR24 webpage lets you do that.

The position data seems to be spot on in this case and you can see other aircraft back taxi on runway 26 and turn around at the end on the playback so I don't think there is much of a map shift in the FR24/Google Earth depiction.

But, even with an altitude error, it seems odd that the descent continues halfway down the runway in the plot.

B744 Go around procedure :

...Auto pilot can be reengaged in stable conditions.

Wouldn't the autopilot normally remain engaged for a low-vis go around from a coupled CAT II approach?

Obviously something that wasn't normal happened in this case...

peekay4

16th Jan 2017, 18:19

In any case, I remain unconvinced that it's a useful tool for finding out what happened and I suspect those that do actual investigative work including the interpretation of the recorders, will concur.
On the contrary, board investigators will consider all data available, subject to their limitations.

In fact FR24 data have been requested by investigators in several high profile cases, including the Germanwings crash in the Alps and the Metrojet crash in Egypt.

One difference: sites like FR24 can provide investigators with the full set of raw ADS-B data, which we don't get from the basic website. Having access to the raw data enables better analysis of the data's characteristics and limitations.

Icelanta

16th Jan 2017, 18:29

Douglas744 is correct with his explanations.
However, no TO/GA mode is not really a big issue. Your hands should always follow the throttles anyhow and move them forward on a GA. ('Basic airmanship).

It is not possible to overboost the engines if the EEC's are operative.
1 click of the TOGA: 2000'/min. ROC, annunciated as THR ( the thrust needed for a requested vertical profile)
Second click: Full GA thrust, Annunciated as THR REF ( all available thrust)

LNAV or HDG SEL at 400'
VNAV at 1000' ( Boeing procedures)

Some more observations:
TO/GA will remain armed until 2 seconds after 5ft. RA ( some manuals state 2 sec. after touchdown)

As I mentioned before, in case of no auto retard of the AFDS at 25ft. RA, the aircraft will not touch down and fly happily a couple of feet high With Vref along the runway.

Airbubba

16th Jan 2017, 18:51

As I mentioned before, in case of no auto retard of the AFDS at 25ft. RA, the aircraft will not touch down and fly happily a couple of feet high With Vref along the runway.

It seems like I've flown with an EGWPS or AFDS update that will annunciate this condition as 'LONG FLARE', does this sound right?

2016parks

16th Jan 2017, 19:37

It appears from the maps that that the village (impact area) is situated on a ridgeline that is significantly higher in elevation than the airfield. I can't find that information readily, though. How much higher, and would that have been enough to affect this go around?

atpcliff

16th Jan 2017, 19:40

I read it was a fuel stop. We usually stop in Kazakhstan for fuel on that type of fight/routing. I have only flown the plane about 6 years. One time autoland was planned, but it leveled off at 50' and wouldn't come down. The -400 , seems to have more automation errors now as they get older.

Romasik

16th Jan 2017, 20:35

Can anybody remind me an accident that happened in bad weather (near the minima) for the reason other then pilot mistake. I just can't recall.

Icelanta

16th Jan 2017, 21:01

Airbubba,

I have not heard that call, but this might be part of the RAAS system, which is optional ( some of our aircraft are equipped, some not (yet) )
RAAS is also customizable to include additional callouts.
I do not know if ACT has this system onboard their fleet.

nivsy

16th Jan 2017, 21:14

The aircraft in happier times departing HKG.

tdracer

16th Jan 2017, 21:20

Itsa question i have raised before but there have been a lot of 747F crashes compared to the vastly more numerous pax versions.
There are aspects of pure cargo operations that can make it potentially more hazardous than hauling SLF. For example, as someone else noted, the three most recent 747F crashes (prior to this) were due to cargo fires or shifting cargo - both of which are a significantly greater danger during pure cargo operations. Freighters tend to operate much closer to MTOW/MLW and with more cycles (trading cargo for range with planned refueling stops).
All that being said, the 747F hull loss rate is still pretty respectable. Also, it's no longer the case that passenger 747s are more numerous - the majority of 747s currently in operation are either pure freighters or freighter conversions.

A0283

16th Jan 2017, 22:58

@romasik... Can anybody remind me an accident that happened in bad weather (near the minima) for the reason other then pilot mistake. I just can't recall.

Might be helpful if you make your question more specific. For example ... Do you mean in any phase of flight or just on final approach and landing... ?

( Note that the definition that I use myself is to view accidents as being 'a basically complex chain of events'. In that context there are no single cause accidents, which is also true for 'pilot mistake'. )

oblivia

17th Jan 2017, 01:05

https://aviation-safety.net/database/types/Boeing-747/losses

It's definitely true that there have been more cargo hull losses recently with 747s, but also true that few have been caused purely by pilot error. They're just old planes that are increasingly moving from passenger operations to cargo.

Bobman84

17th Jan 2017, 01:37

It's definitely true that there have been more cargo hull losses recently with 747s, but also true that few have been caused purely by pilot error. They're just old planes that are increasingly moving from passenger operations to cargo.

With respect, the only "old" and "converted" cargo plane to crash in the last 7 years was the National Air Cargo crash in Bagram. The UPS & Asiana crashes were purpose-built freighters with an age of only 2 & 5 years respectively.

keepitrealok

17th Jan 2017, 02:57

Originally Posted by Icelanta
However, no TO/GA mode is not really a big issue. Your hands should always follow the throttles anyhow and move them forward on a GA. ('Basic airmanship).

Although still awaiting the final report, the Emirates B777 accident may show that unfortunately this is not the case.

QDMQDMQDM

17th Jan 2017, 06:26

https://www.austrianwings.info/2017/01/in-eigener-sache-turkish-airlines-will-nach-absturz-von-frachter-bericht-zensurieren-lassen/

"Anders lässt sich nicht erklären, dass der von Turkish Airlines beauftragte in Wien ansässige Rechtsanwalt Mehmet Saim Akagündüz uns namens seiner Mandanschaft auffordert, den Bericht über den Absturz der 747 in Bishkek (man lasse sich die Formulierung auf der Zunge zergehen) so "zu korrigieren", dass "keine Assoziationen mehr zu Turkish Airlines hergestellt werden können"."

This report in German from the Austrian aviation publication, Austrian Wings, states that Turkish Airlines has threatened them with legal action unless they remove any association whatsoever between this aircraft and Turkish Airlines from their article. The aircraft was a wet leased MyCargo aircraft, flying under a Turkish Airlines flight number.

In the article the editor says he wants the world to know the methods by which Turkish Airlines attempts to censor the truth and prevent any worsening of its already poor safety statistics. He seems jolly irate.

Anyway, now the world knows.

Romasik

17th Jan 2017, 07:14

@romasik...

Might be helpful if you make your question more specific. For example ... Do you mean in any phase of flight or just on final approach and landing... ?

( Note that the definition that I use myself is to view accidents as being 'a basically complex chain of events'. In that context there are no single cause accidents, which is also true for 'pilot mistake'. )
On final approach and landing. Everything is going on smoothly and then all of a sudden during a very short time interval from passing DA to somewhere on initial GA aircrft falls from the sky.
My point is that the probabilty of a critical pilot mistake during these maneuvers in bad weather coinciding with critical aircraft system failure is kind of minuscule.

Volume

17th Jan 2017, 07:16

there have been a lot of 747F crashes compared to the vastly more numerous pax versionsI think this is indeed a very interesting point. There are a lot of aircraft types which are operate in large numbers as freighters and pax aircraft (MD-11, A300-600, 767, 757, 727...), but for none of them the difference in accident statistics is as striking as for the 747-400, which has an outstanding statistics as pax aircraft (especially compared to the -100 to -300 model) but a lower than average one as a cargo aircraft (basically no difference to the -100 to -300 models). This should tell us something. Are the typical freighter issues (fire, load shift) increasing with size? Are the 747-400 freighters that crashed especially old / high cycle machines? Are these aircraft especially cheap on the market, so that a lot of them are operated by "less quality" operators? Are these aircraft maintained using the huge amount of used parts from the high number of retired pax aircraft? Is it a special type of pilot flying these planes? (on the other hand, many crashes are not pilot error...) Are they operated closer to the limits (e.g. landing weight)? For sure there is something to learn from the numbers.

peekay4

17th Jan 2017, 07:32

Cargo ops in general has about 2x to 5x the accident rate vs. passenger ops.

There are many reasons, including differing regulations, loading / w&b issues, hazardous materials, less stringent flight time limits (fatigue), more night ops, maintenance issue with older aircraft, etc.

ahmbay

17th Jan 2017, 09:07

i'm thinking it can be a cargo shift or some malfunction, i cant understand why they didn't climbed after RW finishes.

Icelanta

17th Jan 2017, 09:28

Guys, the main cargo deck was probably full with pallets ( 86'tons).
Load shift is not very probable, the pallets themselves are not that heavy normally flying out of HK, and one pallet getting loose will do nothing in reality on B744.
Please do not compare with the National crash in Bagram. That was an extremely heavy non-standard Military load ( trucks) that had never been transported in such quantity on a National flight, and was secured incorrectly.

Regarding the claim that regulations for cargo flights are different: that is NOT correct. Same duty limitations, same training and licence requirements.
Most cargo operators give training to their crews that is on par or better than passenger carrying airlines. Think Cargolux, TNT, EAT,... No pay-to-fly... of course, there are always some companies that do anything to " get the job done" and to outprice competitors.
I will not give my opinion in public regarding maintenance and operating standards of ACT however.

The company I fly for ( with excellent training standards and maintenance by the way) operates both the Passenger-and Cargo version of the B744. We fly mixed fleet, traning is the same ( actually, more things to take into account on a cargo flight, like smoke avoidance procedures due hot and humid ops).

If they went around from the DA ( 100'), then one would excpect them to be at least at around 2000' over the crash-site.
The debris do not look to result from a high-impact crash like the Flydubai go-around crash ( very high fragmentation), same goes for the National Bagram accident. ( high fragmentation).

ManaAdaSystem

17th Jan 2017, 09:48

Looks more like the EK 777 crash if it had happened over/into a village?

TURIN

17th Jan 2017, 10:00

From the press release.

There are no faults recorded in the technical log book of the aircraft.

What about the one in the locked cupboard back at base? :suspect:

It wouldn't be the first time.

VR-HFX

17th Jan 2017, 10:34

Mag plug

I'm with you. I have over 15k hours on the 74 in all it's forms. This is obviously a missed approach and GA that has gone terribly wrong for whatever reason. Low hours on type and ****e wx obviously a major factor plus circadian issues but reliance on auto throttle and TOGA is probably where it all went wrong.

airsound

17th Jan 2017, 11:16

2016Parks

Welcome aboard the PPRuNe rollercoaster...

You saythe village (impact area) is situated on a ridgeline that is significantly higher in elevation than the airfieldI don't think so. Google Earth shows elevation of the 08 threshold as ⋍638m (agrees with World Aero Data), and the edge of the village as 639m - so more or less flat.

It also shows that the distance of the 08 threshold from the edge of the village is 855m (⋍half a mile). Avherald says the impact was 1100m from the runway, so maybe 245m into the village from the boundary.

airsound

act700

17th Jan 2017, 11:17

Don't forget your roots, all you xx-thousand hour gods...you too were 'low time on type' at some point...and somehow it all worked out, right?
I just don't buy this argument-besides, 800+ on type is more than enough to know one's way around.

But none of that really matters until some competent authority hints at what went wrong here.

Holy crap, I haven't been on here in forever!! Do I not have a life anymore??

guadaMB

17th Jan 2017, 13:26

@act700
Don't forget your roots, all you xx-thousand hour gods...you too were 'low time on type' at some point...and somehow it all worked out, right?
I just don't buy this argument-besides, 800+ on type is more than enough to know one's way around.

:ok:

peekay4

17th Jan 2017, 13:35

Regarding the claim that regulations for cargo flights are different: that is NOT correct. Same duty limitations, same training and licence requirements.

That's NOT correct around the world. E.g., in the US, new FAR Part 117 rest & duty limits passed after the Colgan crash specifically exempts all-cargo ops.

Hotel Tango

17th Jan 2017, 13:43

Kulverstukas

17th Jan 2017, 13:55

Volume

17th Jan 2017, 14:18

A shift in altitude and position is normal in FR24. A horizontal shift by 4 km would be a lot, but not unheared of.
All this data tells us, is that the approach was stable until the very end of the transmitted data.

Do we know by now whether this has been an ILS approach or a GPS approach?
All reports say go-around, at least one engine is missing all its fan blades, looks like a crash at full power (of at least one engine, to be exact). Post impact fire shows plenty of fuel was left. The rest is gueswork from here. Maybe locals know more.

Kulverstukas

17th Jan 2017, 14:30

A shift in altitude and position is normal in FR24. A horizontal shift by 4 km would be a lot, but not unheared of.

FR24 shows quite reliable horizontal position of route and last known point in this case.

https://blog.flightradar24.com/blog/wp-content/uploads/2017/01/Additional-Decoded-Data-TK6491.jpg

peekay4

17th Jan 2017, 14:32

(Edit: Kulverstukas beat me to it).

Icelanta

17th Jan 2017, 14:32

The rwy has only an ILS ( cat II) or a non-precision VOR approach. No Rnav approaches.
Besides, it were LVP's.

An ILS is an ILS. It guides you towards the touchdown point on a given runway.
Not 4km. Behind it.

An LNAV/VNAV approach could guide you to the wrong spot obviously ( map shift, although very uncommon on B744) but I can not even start to imagine why the crew would be doing this.
I would not trust FR24 data.

peekay4

17th Jan 2017, 14:36

It would be extremely strange for ADS-B data to be shifted precisely in the runway direction, precisely along the extended centerline, and precisely ending at the actual crash location.

Absent other data, for now it seems more probable that the FR24 data is correct and the aircraft was not on the CAT II ILS DME 26 glideslope.

Kulverstukas

17th Jan 2017, 14:40

I also read in local forums that besides Bishkek airport was renovated, VOR/DME equipment is obsolete and strongly needs repair

Icelanta

17th Jan 2017, 14:46

But what could cause this when you follow an ILS cat2 for rwy26?!
I see no possibility to be that much offset in GS if you follow an ILS. The AFDS reverts to raw data when the ILS is identified and captured and follows it until 200ft. After which it will follow stored points and data up to touchdown, crosschecked with raw data to avoid ground interference.

Anybody have an explanation?

Magplug

17th Jan 2017, 14:47

@Kulverstukas I also ran the figures and came to the same inexplicable conclusion.

I can say from my observations of the ADS data.....

- The approach was established Vref +5 prior to 1000' AAL so a stable approach.
- The descent rate was consistent with a 3deg glideslope, a false G/s capture would have been steeper but descending to the same correct touchdown point.
- The ROD was consistently accurate as one would expect with an ILS approach coupled to the autopilot.
- The QDM tracking is also very accurate for the same reason.
- The data at the end appears to show a GA from just below 100' AGL

......Which is all very inconsistent with the aircraft then crashing. Can this ADS-B data be considered accurate?

Those discussing the rising terrain upwind of the runway... Remember the crew is basing their GA decision on the Radio Altimeter at ~100' RA so even if they were well upwind of the correct touchdown point, the Rad Alt will still give you accurate ground separation for the GA decision.

If the crew were trying to grub-in below the weather.... there is no evidence of anything other than a continuous 3 deg descent followed by a GA.

I notice the ILS frequencies at both ends are identical. I wonder if some human error on the ground might present the correct localiser signal for 26 but a glideslope backbeam for the touchdown point of runway 08?

That would be more consistent with the trajectory of the accident aircraft.

donotdespisethesnake

17th Jan 2017, 15:17

If we take in account FR24 height data (including last recovered points) it seems that they aim in the point ~900m right after the further end of the rwy, which is marked 0 on the graph

https://cdn.aviaforum.ru/images/2017/01/821968_ae4d033d817ea9afdf7437e3a2866c34.png

The last data points at ~600 ft altitude are not credible IMO. It does not look like LOC during GA. If there was an attempt at GA, it had no effect, because at that point they were in contact with the ground well beyond the end of the runway.

Icelanta

17th Jan 2017, 15:25

Where there any aircraft landing before the ACT, if so, how much before?

Ex Cargo Clown

17th Jan 2017, 16:22

Looks odd this, wrong ILS G/S trapped from the backcourse?

Magplug

17th Jan 2017, 16:27

Didn't I just say that ?????

Icelanta

17th Jan 2017, 16:37

peekay4

17th Jan 2017, 16:46

fepate

17th Jan 2017, 16:57

I'd think the path from a false LOC BC GS signal would not look like the steady descent profile we see from the ADS-B data.

Btw I compared FR24 data with Flightaware data. They seem to be from different sets of ADS-B receivers (possibly overlapping), but the data over the runway match within +/- 25ft altitude and < 100m position along the centerline. I.e., both show the aircraft well above where it should have been, well past the runway threshold.

Someone else asked if there were aircraft approaching that runway prior to this one. If so, how did the FR24/FlightAware vertical profile compare? Is someone willing to dig that data up?

Airbubba

17th Jan 2017, 17:05

FR24 shows quite reliable horizontal position of route and last known point in this case.

It would be extremely strange for ADS-B data to be shifted precisely in the runway direction, precisely along the extended centerline, and precisely ending at the actual crash location.

Absent other data, for now it seems more probable that the FR24 data is correct and the aircraft was not on the CAT II ILS DME 26 glideslope.

An ILS is an ILS. It guides you towards the touchdown point on a given runway.
Not 4km. Behind it.

Another crosscheck on the positional accuracy of the ADS-B data can be made by looking at the departure taxi from the cargo ramp in HKG to runway 07L. The turns are in the right place and the plane stays right on the centerline. This was hours earlier and things can change or drift if IRS position or faulty radio nav is somehow put into the mix I suppose. This plane was a former SQ freighter, anybody here know how they were spec'd for initial ADS-B installations?

Looking at the vertical approach profile in the FR24 .kml file it looks to me like possibly the glide slope was captured from above. Or, was it chased with vertical speed and paralleled a dot high with the throttles back to try to get on profile and never captured before minimums?

On some aircraft if you arm the approach while above the glideslope you get a roller coaster pitch over to capture so the 'technique' was to get right on the path with vertical speed and LOC and then arm the G/S when it was centered. As things got stable it was easy to forget to arm the glideslope. Or, so I'm told. Nowadays if things aren't right inside the marker you break it off and sort it out before another try. At least, that's what we are supposed to do.

Was this really a stable approach? Take a look at the groundspeeds in the FR24 and FlightAware data. It appears that the plane was still decelerating significantly all the way down the glideslope. This may have been due to a decreasing tailwind in the descent or maybe late configuration for the approach, either way with light runway winds looks like the power was back to lose speed as they approached the runway.

Where there any aircraft landing before the ACT, if so, how much before?

On FR24 the previous landing appears to be Aeroflot 1882, an A321 from SVO at about 0010Z, a little over an hour earlier. They appear to touch down in the landing zone and take the mid-field turnoff to the ramp.

DaveReidUK

17th Jan 2017, 17:10

I'd think the path from a false LOC BC GS signal would not look like the steady descent profile we see from the ADS-B data.

Btw I compared FR24 data with Flightaware data. They seem to be from different sets of ADS-B receivers (possibly overlapping), but the data over the runway match within +/- 25ft altitude and < 100m position along the centerline. I.e., both show the aircraft well above where it should have been, well past the runway threshold.

The two sources are consistent, but that doesn't mean they are accurate.

We have already seen in a previous post (#19) that, based on the QNH in the METAR, the aircraft would have been reporting heights roughly 300' lower than actual.

RoD will, of course, be the same as implied by the ADS-B data.

peekay4

17th Jan 2017, 17:43

We have already seen in a previous post (#19) that, based on the QNH in the METAR, the aircraft would have been reporting heights roughly 300' lower than actual.
Yes but that just makes it worse, doesn't it? I mean, the aircraft would be even higher (above the GS position) than where it was supposed to be.

Just the fact that the data shows a steady descent (with no leveling off), if the ADS-B horizontal positions are correct (as they appear to be) then must conclude that the aircraft was well above where it should have been, well past the runway threshold.

Airbubba

17th Jan 2017, 17:45

Someone else asked if there were aircraft approaching that runway prior to this one. If so, how did the FR24/FlightAware vertical profile compare? Is someone willing to dig that data up?

SU1882 turned onto the approach from the north, TK6491 came up from the south.

It looks like the 747 overshot the localizer slightly showing a 218 knot groundspeed on the turn to final.

TK6491 plots well above the path of SU1882 in the FR24 .kml files.

At roughly the same position on short final, TK6491 shows 3100 feet, 185 knots, heading 259 degrees and SU1882 shows 2040 feet, 140 knots and heading 259 degrees.

You can download these .kml files and open them simultaneously with Google Earth. You can also play with the tilt to check the vertical path profile.

Get the .kml files for January 15 here:

https://www.flightradar24.com/data/flights/tk6491/#c2d9d64

https://www.flightradar24.com/data/flights/su1882/#c2da9c3

Magplug

17th Jan 2017, 17:49

But then I would expect the GPWS to start shouting during the approach, resulting in an immediate G/A.
Also, your map on the ND would not coincide with your presumed position according to the glideslope.

I have never heard about such an occurence.

Me neither.... But.... Trying to capture the G/s from above in a B744 is really NOT a good idea. The GPWS will only give a 'Pull Up' if you are BELOW the glideslope. If you are still above the G/s trying to capture it from above there is no warning provided the aircraft is in the landing config. A crew that attempts to capture from above then fails to notice the lack of G/s capture, carrying on in V/s to 100' RA is in big trouble. My guess is that's what happened.

The Enhanced GPWS will call-out to trap an off-field landing but the 'safe-zone' around any airfield is not related to the selected runway in the FMC so the area around the threshold of FRU08 is also a 'safe-zone'...... Food for thought.

peekay4

17th Jan 2017, 17:57

Another possible factor is that the DME for ILS RWY 26 is actually measured from the opposite runway threshold (i.e., it reads 2.2nm at RWY 26 threshold, zero at RWY 08 threshold). This could've added to any confusion if the crew were chasing the G/S from above and looking at the DME to check distance to the runway.

FIRESYSOK

17th Jan 2017, 18:02

The Enhanced GPWS will call-out to trap an off-field landing but the 'safe-zone' around any airfield is not related to the selected runway in the FMC so the area around the threshold of FRU08 is also a 'safe-zone'...... Food for thought.

That's not quite correct. EGPWS does in fact have thousands of runways in its database. It matters not which is selected in the FMC, but rather a terrain clearance floor is tailored for each runway at every airport in the enhanced EGPWS database.

Magplug

17th Jan 2017, 18:07

So what did I say that was incorrect ?

readywhenreaching

17th Jan 2017, 18:11

You can download these .kml files and open them simultaneously with Google Earth. You can also play with the tilt to check the vertical path profile.

Get the .kml files for January 15 here:

FR24 commercialized the .KML's. Only $-members can see it.

peekay4

17th Jan 2017, 18:13

The TK6491 .KML and other data files can be downloaded for free from below:

https://www.flightradar24.com/blog/crash-of-mycargoact-airlines-flight-tk6491-and-additional-ads-b-data/

FullWings

17th Jan 2017, 18:46

Interesting discussion of a near accident involving ILS glideslope here (PPRuNe) ("http://www.pprune.org/private-flying/262577-interesting-ils-failure-mode.html”)

FIRESYSOK

17th Jan 2017, 18:52

So what did I say that was incorrect ?

Yes there would be a 'safe zone' at the runway threshold but mentioning FMC runway selection isn't relevant leading one [some] to believe EGPWS isn't runway specific.

I will say that if the information that this flight was higher than a previous arrival is correct, your suggestion that glide slope was never captured and the flight remained in a VS mode, is quite possible. This wouldn't be the first time recalling an Air Europa charter landing in Katowice that 'landed' short of the runway.

Additionally, a high descent rate from either a false glideslope or selected VS would result in low thrust and high inertia that, once GPWS Mode 1/2 became active, could result in an unexpected state from which a go-around would be more challenging.

All that said, I would hope either scenario would be trapped much earlier at the stabilisation 'gates', but a less-than-fresh crew is always a threat in any operation.

Airbubba

17th Jan 2017, 18:57

FR24 commercialized the .KML's. Only $-members can see it.

Sorry, I didn't realize that. See if you can access these FlightAware logs to compare the speeds and altitudes on final, the 747 seems to me to be smoking down the glidepath (or above it :eek:) for a low-viz approach, even for a whale:

Flight Track Log THY6491 16-Jan-2017 HKG / VHHH - FRU / UCFM FlightAware (http://flightaware.com/live/flight/THY6491/history/20170115/1710Z/VHHH/UCFM/tracklog)

Flight Track Log AFL1882 15-Jan-2017 SVO / UUEE - FRU / UCFM FlightAware (http://flightaware.com/live/flight/AFL1882/history/20170115/1855Z/UUEE/UCFM/tracklog)

The A321 appears to have a stable approach on the turn to final for runway 26 with maybe a 10 knot reduction close to the runway.

Icelanta

17th Jan 2017, 19:04

FR24 has the vertical path as a steady 750ft/min. ROD?
That does not look at all like a crew that is trying to get onto the glideslope from above, but is a perfect 3 degrees glideslope.

For some reason, IF date from FR24 is correct, the aircraft was flying a "phantom. ILS" around 4km. Offset to the West.
Now there is only one way I see this happening, and that would imply a total lack of procedures, and I will not put this on a public forum. So what can cause this "phantom ILS", knowing that aircraft have used the ILS before the accident without any issue it seems.

Airbubba

17th Jan 2017, 19:27

FR24 has the vertical path as a steady 750ft/min. ROD?

It looks to me like they are descending on average at a higher rate than that. Wouldn't they have to be with that groundspeed to maintain 3 degrees?

Avenger

17th Jan 2017, 19:44

Bishkek can be hell on the approach, but in this case I doubt it was turbulence, the RVR seems on the "limits" and the missed approach is a right turn needing a hefty climb gradient. Like Katmandu, this will just be "pilot error", either attempting to line up with something other than the RW lights or botched GA, maybe executed too low to bulk the landing. In this part of the world the METAR is taken with a large pinch of salt..

klintE

17th Jan 2017, 19:51

Any chance this acccident was similiar to KAL801 which crashed on Guam?
They've decided to use localizer and DME when GS wasn't available.
However, their recognition of DME location was incorrect and finally they hit the Nimitz Hill.

Icelanta

17th Jan 2017, 20:14

No.
Only a Cat2 ILS was possible.
The MNS VOR/DME whose reading are mentioned on the ILS26 chart, is situated BEFORE the threshold by the way.

The Missed approach calls for a standard 2.5%.and is straightforward.

Approach speed would be between 150kts. And 160kts. If heavy.

Pneumatix

17th Jan 2017, 20:36

ILS Signal Interference

For some reason, IF date from FR24 is correct, the aircraft was flying a "phantom. ILS" around 4km.

According to FR24 data flight path, a phantom ILS glide slope is a realistic investigation point. The signal may be deviated by a truck or an aircraft on ground. A mobile service equipment may have been in the critical ILS area during the approach.

Full case on French BEA web site / Report: Air France A318 and Transavia B738 at Nantes on May 25th 2010, loss of runway separation in low visibility, ILS disturbance (http://avherald.com/h?article=443c6026)

Magplug

17th Jan 2017, 21:25

@FIRESYSOK

Yes there would be a 'safe zone' at the runway threshold but mentioning FMC runway selection isn't relevant leading one [some] to believe EGPWS isn't runway specific.

I didn't say the FMC runway selection was relevent to EPGWS, I said it was completely irrelevent. Please don't chastise me for something I didn't say.

Can any of my fellow B744 pilots here imagine a crew going through 1000' for an autoland with G/S still armed in V/s without 'Land 3' staring them in the face ???

Herod

17th Jan 2017, 21:27

I don't know about modern installations, but in my day, intercepting the G/S was always to be done from below because of the possibility of a false G/S being propagated above the real one. Came up on the ATPL course in '76 IIRC.

klintE

17th Jan 2017, 21:30

No.
Only a Cat2 ILS was possible.
The MNS VOR/DME whose reading are mentioned on the ILS26 chart, is situated BEFORE the threshold by the way.

Yes. But NDB for RWY08 is situated almost exactly where they crashed. Suppose this is just coincidence (no irony)

Icelanta

17th Jan 2017, 21:30

Pneumatix,

Interference from. a ground based vehicule or aircraft will fluctuate the signal a couple of meters...not 4 km. ...

As I am a Captain on B744, I will follow this accident and investigation with great interest.

Icelanta

17th Jan 2017, 21:39

Herod,

Correct, it is possible to intercept a false lobe.
However, correct and false lobe will still have the same touchdown point.
You can intercept an ILS from above on B744 in a safe way. Let's face it, we all have have to do this from time to time. Doing it correctly though must be trained and demonstrated, and it potential dangers explained and shown. And remember: approach not safe and sound? GO AROUND.

CaptainMongo

17th Jan 2017, 21:54

act700, I understand and agree with you up to a point. However, GA's are not all that frequent. So one may ponder whether said Captain had, in those 800 hours on the B744, ever experienced a GA and (again specifically on the B744) what sort of training for such an event had the airline given him?

"General statistics

Before detailing the results of the survey, the BEA estimated the number of go-arounds performed by a pilot during his/her career, based on the figures communicated by Air France and those supplied by the main European airports. In general, these showed:

� Between 2 and 4 go-arounds per one thousand flights are recorded each year
� A medium-haul flight crew performs on average one go-around a year
� A long-haul flight crew performs on average one go-around every 5 to 10 years."

https://www.bea.aero/etudes/asaga/asaga.study.pdf

ExSp33db1rd

17th Jan 2017, 22:05

And remember: approach not safe and sound? GO AROUND.

Exactly, as a young, soon to be RAF trainee pilot my then girl friends father, an ex-WWII Wellington pilot said - if you remember nothing else, remember this ....."When in doubt lash out" Power, pitch, mixture, carb heat, flaps, everything forward for speed. Concept still relevant despite being a 747

CurtainTwitcher

17th Jan 2017, 22:19

Not suggesting this was the cause of this accident, however mention of glideslope capture from above rattled around in my brain recalling a safety warning published a couple of years ago which I have managed to find: Unexpected autopilot behaviour on ILS approach when intercepting the glide path from above (http://web.archive.org/web/20170117231323/http://www.airservicesaustralia.com/wp-content/uploads/Safety-Bulletin-14-February-2014-Autopilot-behaviour-when-intercepting-ILS.pdf) based on a 2013 event at Eindhoven ( Pitch Up Upsets due to ILS false Glide Slopes (http://skybrary.aero/bookshelf/books/3452.pdf)).

Both worth a read.

act700

18th Jan 2017, 01:14

Hotel Tango, again, I do not buy or accept that line of reasoning! If you are qualified on type, irregardless of hours, you should be able to perform any normal maneuver on that type.

"act700, I understand and agree with you up to a point. However, GA's are not all that frequent. So one may ponder whether said Captain had, in those 800 hours on the B744, ever experienced a GA and (again specifically on the B744) what sort of training for such an event had the airline given him"

ACMS

18th Jan 2017, 01:23

Captainmongo:----

Ok but we do maybe 6 or more missed approaches/go arounds from various situations each year in the Simulator under varying conditions. We have done for 20 years now so I'd suggest that over that time I've done 120 in the Sim and maybe another 15 in the actual Aircraft.

SMT Member

18th Jan 2017, 06:15

Avenger

18th Jan 2017, 06:28

If they were attempting an auto land, according to the post contributions their speed should have been circa 150/160 kts but one post commented according to "data" their speed was 185kts? What would be their GA performance at known weight with anti ice ON?

DaveReidUK

18th Jan 2017, 07:26

If they were attempting an auto land, according to the post contributions their speed should have been circa 150/160 kts but one post commented according to "data" their speed was 185kts?

The aforementioned data doesn't include either TAS or IAS. Groundspeed over the threshold was around 176 kts, surface wind negligible.

Nieuport28

18th Jan 2017, 14:24

Sailvi767

18th Jan 2017, 15:14

Is it possible they decided to throw away the approach at a height of around 2000ft, by arresting the descent, but somehow the auto throttle didn't wake up? Would that explain the 'long drift' down the runway and, having run out of airspeed, result in a stall and crash?

If the autotrottle did not wake up then the pilots were asleep also. Every aircraft I have ever flown be it Airbus, Douglas, Boeing, Lockheed you straighten out your throttle arm as the first thing on a GA. Not a terribly difficult thing to do.

Hotel Tango

18th Jan 2017, 15:45

If you are qualified on type, irregardless of hours, you should be able to perform any normal maneuver on that type.

Sorry, I disagree! The key word is "qualified". How "qualified" one is can arguably depend a great deal on training received on the type and how proficient the country's regulatory authority is.

Kulverstukas

18th Jan 2017, 16:38

https://cdn.aviaforum.ru/images/2017/01/822105_b2236caa1b5b3bae21b0171c0e3d678b.jpg

http://diesel.elcat.kg/index.php?act=attach&type=post&id=13716787

Kulverstukas

18th Jan 2017, 16:40

Second recorder was found today.

MrSnuggles

18th Jan 2017, 16:43

Kulverstukas

Your contributions are always excellent. However, in this case my Russian skills fail me.

Could you please specify exactly what the above chart is supposed to be? I have my suspicions but dare not show my ignorance about these things....

Kulverstukas

18th Jan 2017, 16:55

It's the damage zone on the blueprint of this tiny house village. Violet means buildings on this patch are damaged (and with cut-off roofs), red - totally destroyed.

Kulverstukas

18th Jan 2017, 16:58

PS: Grim pun is that this village name is "Aeroflot garden-house community"

Airbubba

18th Jan 2017, 17:00

Thanks as always Kulverstukas.

Looks like the approach pictured above is to runway 8. You can see the striped building with the marker beacon antenna in the foreground, it was in one of your earlier photos of the wreckage.

barry lloyd

18th Jan 2017, 17:19

PS: Grim pun is that this village name is "Aeroflot garden-house community"

Kulverstukas:

I don't want to derail this important thread, but I've travelled widely in the FSU, though not to Bishkek. I've never heard of such a community before. Does this suggest that the people in this community worked at the airport?

Kulverstukas

18th Jan 2017, 17:45

Kulverstukas:

I don't want to derail this important thread, but I've travelled widely in the FSU, though not to Bishkek. I've never heard of such a community before. Does this suggest that the people in this community worked at the airport?

It's not country-wide, it's usually local community. Possibly, in USSR time this patches was provided for airport workers (see, it's just 400 sq.m each) for growing fruits and vegetables. Usually it was in form of non-pofit cooperative. I think that if you put "aeroflot village" in google map (https://www.google.ru/search?q=%D0%A1%D0%B0%D0%B4%D0%BE%D0%B2%D0%BE%D0%B4%D1%87%D0 %B5%D1%81%D0%BA%D0%BE%D0%B5+%D1%82%D0%BE%D0%B2%D0%B0%D1%80%D 0%B8%D1%89%D0%B5%D1%81%D1%82%D0%B2%D0%BE+%D0%B0%D1%8D%D1%80% D0%BE%D1%84%D0%BB%D0%BE%D1%82&hl=en&authuser=0) you will find a thousands of them.

Chronus

18th Jan 2017, 18:28

Kulverstukas

18th Jan 2017, 18:40

You are right about term. Any non-temporary buildings was prohibited on such a patches. After USSR collapse, usually such patches are privatized (based on "property rights because owned for a long time"), changed status and frequently are used for summer (or even year round) dwelling.

barry lloyd

18th Jan 2017, 18:56

Kulverstukas:

Большое спасибо!

I just followed your link and found one near Ramenskoe which I remember now.

Airbubba

18th Jan 2017, 20:06

A third ADS-B dataset for TK6491 is available here at RadarBox24, it might require some sort of subscription or registration:

https://www.radarbox24.com/data/flights/tk6491#148232065

The speed data is less finely sampled than with FR24 or FlightAware but it does appear to agree that the plane was decelerating all the way down the path to the runway.

If they did have the power back to idle trying to slow down descending into freezing fog, wouldn't those Pratts still have plenty of anti-ice capability with normal pneumatics? On some ETOPS twins you have a minimum power setting for anti-ice with a single bleed source but it is normally not a player with everything working.

scanelpan

18th Jan 2017, 22:00

I have a question for active B747-400 pilots. Being retired for almost 10 years, its too long ago to answer the question myself. Some of you here talk about FR24 Data show a stable approach, others talk about a decellerated approach, all the way down. Most of you seem to agree, the data show a three degree approach angle, between 300 and 500 ft above the ILS Glideslope. My question: would it be possible to program the FMCs to perform a LNAV/VNAV approach with RW26 as active runway, but with final descent waypoint (mistakably) threshold RW08? I could not think of a good reason to use such a construction under the prevailing conditions, so I want to emphasize, its a technical question only.

By the way, I have seen Map shifts on the B747-400 on numerous occasions, even up to 6 nm, but it was back in days, where our 747's were not yet equipped with GPS. Didn't observe them after GPS installment. Assume MyCargo Airlines fleet of 8 747's was GPS equipped.

Icelanta

18th Jan 2017, 22:16

Scanelpan,

Yes, this is possible, and to be honest, I have already thought about this.
But surely no sane crew would do this...

archae86

18th Jan 2017, 23:56

I'm not a pilot, nor do I know the relevant 747 systems, but understand a little geometry.

Assuming a GPS approach, but with an altitude error instead of a position error of sufficient magnitude to generate the observed descent path, how would a 747 behave once the intended position had been overshot, but without reaching ground level, say because of a data entry error or a system error affecting altitude?

Would there be specific warnings? Would automation change modes or take other actions?

lemme

19th Jan 2017, 00:48

I verified that the FR24 ADS-B position reporting was accurate by looking at the departure and the 13 Jan arrival into Bishkek.

http://i.imgsafe.org/0181ee75bb.png
http://i.imgsafe.org/0183196619.png

I plotted the "additional data" FR24 released to augment the final approach. In addition, I adjusted the reported altitude up by 300 feet to account for the high pressure.

http://i.imgsafe.org/018443c442.png
http://i.imgsafe.org/01852f2ece.png

The approach is offset by more than two miles from where any published approach provides.
TK6491 descended below any appropriate altitude before commencing the go-around.
TK6491 appears to have over-rotated and zoom-climbed. The final resting place suggest it stalled and crashed nearly directly below.

Satcom Guru: TK6491 747-400F MyCargo/ACT Airlines, Manas Airport (FRU/UCFM) in Bishkek (http://www.satcom.guru/2017/01/tk6491-747-400f-mycargoact-airlines.html)

aterpster

19th Jan 2017, 00:54

scanelpan:

The ADSB data are not sufficient in my view. Having said that, nothing has changed about flying an ILS in bad weather; i.e., on GS and on speed and stable passing the final approach fix.

Hopefully, we will eventually learn what the CVR and DFDR recorded.

peekay4

19th Jan 2017, 07:56

Interesting theory sjimmy.

Local reports that both blackboxes were sent to Moscow today for decoding at MAK.

Airbubba

19th Jan 2017, 08:14

TK6491 appears to have over-rotated and zoom-climbed. The final resting place suggest it stalled and crashed nearly directly below.

Satcom Guru: TK6491 747-400F MyCargo/ACT Airlines, Manas Airport (FRU/UCFM) in Bishkek (http://www.satcom.guru/2017/01/tk6491-747-400f-mycargoact-airlines.html)

Not sure I buy the zoom climb, looks to me like the plane was already breaking up as it went to the scene of the accident.

I read that potentially they where high/ above GS.
What one would do to catch the GS is to dial the alt on the MCP to a lower value.
What IF this value was set to 100/200ft AGL on MCP. And at a check height they did not see the wrong GA ALT was set.
Now they end up doing a GA. They press TOGA . Aircraft goes up and directly captures at alt in the MCP window.
Just a theory!

There was a Boeing procedure like this years ago for non-precision approaches with mins set in the window but I don't think it would apply to a low-viz ILS autoland. I'm thinking they were high and fast, started down late, maybe forgot to arm the G/S before turning final and chased the path with vertical speed and the ATHR pulled the throttles back to idle.

peekay4

19th Jan 2017, 08:42

Not sure I buy the zoom climb, looks to me like the plane was already breaking up as it went to the scene of the accident.

I would agree. 30,000 fpm climb doesn't seem credible given weight (momentum) and aerodynamic limits. It also doesn't correlate with the last transmitted ADS-B vertical rate. The last couple ADS-B data points should probably be discarded as outliers -- we may be seeing post-impact effects.

act700

19th Jan 2017, 08:44

Hotel Tango,

"Sorry, I disagree! The key word is "qualified". How "qualified" one is can arguably depend a great deal on training received on the type and how proficient the country's regulatory authority is."

....now we're talking a totally different thing here!! Morals, etc...qualified is qualified, just like the Asiana SFO boys were "very high time and experienced" pilots...

DaveReidUK

19th Jan 2017, 08:44

I plotted the "additional data" FR24 released to augment the final approach. In addition, I adjusted the reported altitude up by 300 feet to account for the high pressure.

http://i.imgsafe.org/01852f2ece.png

If the ADS-B data for those last two points is correct, it represents a height gain of 325 feet (± 50') over a horizontal distance of 175 feet.

That's a heck of a flight path angle.

Hotel Tango

19th Jan 2017, 09:18

qualified is qualified

Sadly, no it's not - for reasons already given. Captain only had 800 hours on type. We don't know what training he received and by whom he was "qualified". With 800 hours long haul flying on this particular type this may well have been his first GA. How he was able to handle that may well come down to the fact that his training (on type) was not adequate. That essentially would not be his fault but that of the authority/person which "qualified" him.

Pali

19th Jan 2017, 09:19

It's not country-wide, it's usually local community. Possibly, in USSR time this patches was provided for airport workers (see, it's just 400 sq.m each) for growing fruits and vegetables. Usually it was in form of non-pofit cooperative. I think that if you put "aeroflot village" in google map (https://www.google.ru/search?q=%D0%A1%D0%B0%D0%B4%D0%BE%D0%B2%D0%BE%D0%B4%D1%87%D0 %B5%D1%81%D0%BA%D0%BE%D0%B5+%D1%82%D0%BE%D0%B2%D0%B0%D1%80%D 0%B8%D1%89%D0%B5%D1%81%D1%82%D0%B2%D0%BE+%D0%B0%D1%8D%D1%80% D0%BE%D1%84%D0%BB%D0%BE%D1%82&hl=en&authuser=0) you will find a thousands of them.

I am bit surprised that there is no regulation to prohibit building any hard structures on the centreline or in the vicinity of it. I can imagine that runway existed there long before any dwellings were built. We don't know yet if the outcome for the crew would be different in case there would be only gardens and fields but I would suggest that areas in the straight line from runway should stay clear in a reasonable distance from an airport fence.

If you watched that video on 727 cargo take off at Puerto Carreno crash (http://www.pprune.org/rumours-news/588549-puerto-carreno-cargo-722-crash.html) recently it may be that hitting hard structure behind the fence possibly severing flaps on the starboard wing was the final Swiss cheese hole which doomed the flight.

We would find quite many cases when built up structures on the prolonged centreline made things worse and I am not certain if given legislation is neglected or it simply doesn't exist.

Why endanger pilots and inhabitants on the ground by such a negligence? :confused:

Magplug

19th Jan 2017, 09:30

Our 744s have twin GPS and NGFMC so we can fly RNAV final approaches down to RNP1 specification. In fact the RNP1 minima are sometimes below the minimum autopilot disconnect height for a NPA so that becomes the lowest MDA.

When flying an RNAV transition or final approach the autopilot MUST be used in both LNAV & VNAV to guarantee the required vertical and horizontal accuracy. The database approach in the FMC MUST be used and cannot be modified in any way by the pilot. You certainly CANNOT build your own approaches. In my docs there are no RNAV approaches at all published at FRU.

With the RVR conditions on the day at around 350M both a Cat II ILS and an automatic landing were mandatory. It is NOT permitted to carry out manual landings with RVR below Cat I conditions (550M for FRU26). The B744 has 3 ILS recievers - It only needs 2 of them to execute an autoland.

Personally I have had a couple of autolands in my career in RVR below 200M where I had to intervene to avert a mishap, but that situation is very rare as automatic landings with rollout are VERY reliable. Consequently Captains tend to be comfortably in the mindset of 'we are landing off this approach'. Where the approach has a visual decision point (like Cat II), that decision is slightly academic because... in the absence of outside influence the aircraft will reliably continue below minima down the ILS, land and safely roll-out with absolutely no pilot input.

It is clear from the traces that the aircraft was accurately established and maintaining the centreline, they were also descending at an accurate ROD consistent with automatic control.... although way above the glide path.

The map of the debris field above is not consistent with a stall from height. This aircraft flew into the ground at medium speed at a shallow angle consistent with the earlier ADS-B ROD figures. I suggest the final ADS-B points suggesting a GA are crash corruption.

I believe this aircraft had captured the localiser but never ever captured the glideslope. They continued to descend in V/s without noticing they were getting higher & higher above the glide. There would have been no 'Land 3' FMA annunciation at 1500', no FLARE or ROLLOUT armed and at 1000' instead of taking control the Captain should order a GA if 'Land 2 or 3' are not showing.

If I am correct and all this is later proven to be true, we are talking about mishandling of epic proportions.

donotdespisethesnake

19th Jan 2017, 09:51

TK6491 appears to have over-rotated and zoom-climbed. The final resting place suggest it stalled and crashed nearly directly below.

The last two data points are impossible, for more than one reason. If you look at the map of impact damage posted recently by Kulverstukas, the last data point is after the first impact occurred. If you ignore the last two data points, and extrapolate the line of descent it is very consistent with the actual impact damage.

What puzzles me is that at RVR of 350m, runway should have been visible in time to abort but apparently no GA was attempted. RVR a lot less or pilots disoriented?

DaveReidUK

19th Jan 2017, 10:15

Amadis of Gaul

19th Jan 2017, 10:49

donotdespisethesnake

19th Jan 2017, 10:57

Really?

http://www.avgen.com/TK6491.jpg

https://c1.staticflickr.com/1/674/32362677196_ea82e788a1_b.jpg
https://c1.staticflickr.com/1/543/32251458862_e92544a3e1_z.jpg

aviator17

19th Jan 2017, 11:05

lomapaseo

19th Jan 2017, 11:26

I don't follow the discussion on TOGA in this accident. Certainly the investigators have seen the engines by now and know what power they were at when they hit the ground.

Magplug

19th Jan 2017, 11:26

....otherwise flare position will be maintained until first obstacle on extended runway centerline (crew may have disorientation due increase in power -false climbing sense?)

There is absolutely no ADS-B data suggesting a period of level flight. What's the point of even suggesting that?

Kulverstukas

19th Jan 2017, 11:30

I verified that the FR24 ADS-B position reporting was accurate by looking at the departure and the 13 Jan arrival into Bishkek.
I plotted the "additional data" FR24 released to augment the final approach. In addition, I adjusted the reported altitude up by 300 feet to account for the high pressure.

thank you for most impressive consolidation of known data, lemme!

I am bit surprised that there is no regulation to prohibit building any hard structures on the centreline or in the vicinity of it.

Why endanger pilots and inhabitants on the ground by such a negligence? :confused:

I's an inevitable outgoings of transition from collective property to private property and then chaos for about 10 years of property and rights legal system change. There is now not only villages in close vicinity of safety grounds of airports, but whole settlements built on high pressure gas or oil pipes or under high voltage power lines, 4-store hotels built at the top of boat garages etc.

Kulverstukas

19th Jan 2017, 11:33

There is absolutely no ADS-B data suggesting a period of level flight. What's the point of even suggesting that?
https://cdn.aviaforum.ru/images/2017/01/822200_6ea89cbf70032aa78ba7da3d73af9ff0.png

X=Distance from threshold.

red - proper glideslope
blue - ADS-B data

PS: recorders will be open 20/01 when Turkish experts arrived to Moscow.

CRayner

19th Jan 2017, 12:24

Irregardless is not a word. Just an FYI.
Irregardless has been in use as a slang conflation of irrespective and regardless for some time now. The first printed record I can find is from Indiana in 1795. So I think it must be accepted that it is a word, in common use by North Americans to mean the same as its root words. Niminy piminy pedants find it offensive as they maintain that the negative initial consonant "irr" adds a further negative to "regardless" thus making a double negative, and so positive meaning. I feel that this is a purely academic objection, and prefer to go with Humpty Dumpty's argument in "Alice Through the Looking Glass". In any case, taking a pragmatic view, I believe that the word is sufficiently current now that its use is unremarkable, and certainly less likely to give rise to confusion than the widely accepted use of strings of initials and acronyms which infest this forum. FYI

Admiral346

19th Jan 2017, 12:45

The distribution of the damage chart does not support a rapid climb and fall of the aircraft.
From east to west first houses are damaged - an indication that the 747 descended into the settlement, then they become destroyed - that's where they hit the ground, then there are more damaged houses - debris of the wreckage hitting and causing damage.

If it had climbed and the dived down, I would expect a spot with destroyed houses, and then damage in the direction of flight (Where pieces of the wreckage would keep moving).

Nic

DaveReidUK

19th Jan 2017, 12:51

The last two data points are impossible, for more than one reason. If you look at the map of impact damage posted recently by Kulverstukas, the last data point is after the first impact occurred.

Lemme's diagram, which you re-posted, doesn't show that. In fact the position of the easternmost damaged house in Kulverstukas' plan almost exactly coincides with the last data point.

http://www.pprune.org/www.avgen.com/TK6491.jpgIf you ignore the last two data points, and extrapolate the line of descent it is very consistent with the actual impact damage.If you arbitrarily ignore selected data points, you can prove just about any theory. :O

peekay4

19th Jan 2017, 12:59

If you arbitrarily ignore selected data points, you can prove just about any theory.

Well considering a fully-loaded 747 at 164 kts, to go from a -320 fpm descent to a +30,000 (!) fpm climb in 1.1 seconds isn't credible and might possibly violate a few laws of physics. So I think excluding the suspect data may be reasonable in this case.

aterpster

19th Jan 2017, 13:06

What Merriam-Webster has to say about it:

Is irregardless a word?

Irregardless was popularized in dialectal American speech in the early 20th century. Its increasingly widespread spoken use called it to the attention of usage commentators as early as 1927. The most frequently repeated remark about it is that “there is no such word.” There is such a word, however. It is still used primarily in speech, although it can be found from time to time in edited prose. Its reputation has not risen over the years, and it is still a long way from general acceptance. Use regardless instead.

Logically, irregardless means "regardless regardless."

MATELO

19th Jan 2017, 13:10

I would suggest that areas in the straight line from runway should stay clear in a reasonable distance from an airport fence.

A trip to LHR would be an eye opener.

donotdespisethesnake

19th Jan 2017, 13:23

Lemme's diagram, which you re-posted, doesn't show that. In fact the position of the easternmost damaged house in Kulverstukas' plan almost exactly coincides with the last data point.:O

So the 747 fell exactly vertically from a few hundred feet up, then magically moved laterally for a few hundred feet? Not happening.

The data points are selected to match reality, not the other way round.

I don't know what alternate universe you are selecting data from. :O

For clarity : I added red and yellow lines to image from lemme. red = extrapolated trajectory, yellow is impact damage recorded on the ground.

DaveReidUK

19th Jan 2017, 13:30

The data points are selected to match reality, not the other way round.

Reality is what the FDR and CVR will tell us.

Until then, everything is speculation.

lomapaseo

19th Jan 2017, 15:25

Reality is what the FDR and CVR will tell us.

Until then, everything is speculation.

There are other views to that :)

I'm not one to ignore the FDR or CVR as it is a source of facts, but neither do I ignore the condition of the wreckage which is immediately before my eyes. It seems the more we rely on the recorders for answers the more likely that one of them is missing or damaged.

In discussion boards like PPrune there would be nothing to discuss for months following a prang if we were to await what gets released from the black boxes.

Airbubba

19th Jan 2017, 15:42

lemme,

In your article posted here:

Satcom Guru: TK6491 747-400F MyCargo/ACT Airlines, Manas Airport (FRU/UCFM) in Bishkek (http://www.satcom.guru/2017/01/tk6491-747-400f-mycargoact-airlines.html)

You seem to show the approach plates and cite the minimums (minima for them grammer police ;)) for runway 08. Is this intentional? The rest of the discussion reflects an approach to runway 26.

Kulverstukas

19th Jan 2017, 15:50

For clarity : I added red and yellow lines to image from lemme. red = extrapolated trajectory, yellow is impact damage recorded on the ground.
Looks like PFL 101 V2.0 :sad:

powtough

19th Jan 2017, 16:09

Anybody know a 747 with installed AoA indicator or new A350 style thrust indicator? So if they were tracking rwy 08 dme it could possible give a false GS. Again this aircraft doesn't track back course and cannot track LNAV except localizer. Must handfly with marker altitude course track control.

Chronus

19th Jan 2017, 16:22

andrasz

19th Jan 2017, 16:30

The wreckage state and layout appears to be very similar to the 2010 Afriqiyah Tripoli accident. There it was a late go-around in low visibility coupled with an undershoot, an overshoot would produce same result.

DaveReidUK

19th Jan 2017, 16:30

Well considering a fully-loaded 747 at 164 kts, to go from a -320 fpm descent to a +30,000 (!) fpm climb in 1.1 seconds isn't credible and might possibly violate a few laws of physics. So I think excluding the suspect data may be reasonable in this case.

Your healthy scepticism is commendable, but I fear you are applying it to the wrong elements of the data.

Hint: Look back at the last 50 seconds of flight as plotted in the Additional Decoded ADS-B Data. Count how many points there are during those 50 seconds where the aircraft appears to be flying backwards (i.e. east). Then think about what in the dataset might be causing that to (apparently) happen.

Airbubba

19th Jan 2017, 16:47

Hint: Look back at the last 50 seconds of flight as plotted in the Additional Decoded ADS-B Data. Count how many points there are during those 50 seconds where the aircraft appears to be flying backwards (i.e. east). Then think about what in the dataset might be causing that to (apparently) happen.

Here's a previously posted link to the 'additional' data:

https://blog.flightradar24.com/blog/wp-content/uploads/2017/01/Additional-Decoded-ADS-B-Data-TK6491.xlsx

It will open as a spreadsheet and you can see that the track is consistently about 260 degrees.

For some reason, when you open a .kml file with Google Earth, the little arrows seem to swing around in unison sometimes as you zoom in and zoom out. :confused:

Magplug

19th Jan 2017, 16:49

https://cdn.aviaforum.ru/images/2017/01/822200_6ea89cbf70032aa78ba7da3d73af9ff0.png

@Kulverstukas:

Your image shows a constant descent from published platform altitude of 3400' (1400' AAL), NOT evidence of a 'TOGA Fail' remaining in 'Flare' mode as incorrectly suggested by aviator17.

MarcK

19th Jan 2017, 17:58

The altitude component of ADSB is based on pressure altitude. It's certainly possible that damage to the pressure altitude reporting system occurred during the last two data points.

vmandr

19th Jan 2017, 18:13

For some reason, when you open a .kml file with Google Earth, the little arrows seem to swing around in unison sometimes as you zoom in and zoom out.

if you need to see the vertical profile, as in the file below, just right-click the kml file on google earth, properties, stye/color tab, click share style button. then on altitude tab click the checkbox 'exntend to ground'. after that, back to style/color tab and change colors etc. press ok to exit. Finally tilt the image, from right hand side command bar (top) top arrow. HTH

for the additional ponts from fr24 xls file. you must create the points and then 'extend to ground' in altitude tab.

1630

Chronus

19th Jan 2017, 18:33

As it seems rather unlikely that the whole mass of the aircraft could have assumed the characteristics of a ballistic missile. If the final ADS-B spike is coincidental with the impact point, could the transmissions be resultant from impact forces acting on systems, instruments and equipment. Perhaps someone with good knowledge of ADS-B architecture may explain the likely signal emission from an event where the system does is not disabled instantaneously along with the whole airframe.

Airbubba

19th Jan 2017, 18:39

if you need to see the vertical profile, as in the file below, just right-click the kml file on google earth, properties, stye/color tab, click share style button. then on altitude tab click the checkbox 'exntend to ground'. after that, back to style/color tab and change colors etc. pres ok to exit. Finally tilt the image, from right hand side command bar (top) top arrow. HTH

1630

Thanks for the tip, I appreciate it! :ok:

What I think maybe what Dave was looking at was the way the little blue track arrows swing around off course in lemme's Google Earth rendering of the additional ADS-B data:

http://i.imgsafe.org/018443c442.png
http://i.imgsafe.org/01852f2ece.png

Satcom Guru: TK6491 747-400F MyCargo/ACT Airlines, Manas Airport (FRU/UCFM) in Bishkek (http://www.satcom.guru/2017/01/tk6491-747-400f-mycargoact-airlines.html)

The .csv data in the .xlsx file linked above shows a consistent track along the runway but when you display the corresponding .kmz file with Google Earth, the arrows seem to swing around as you zoom in and play with the tilt on my Windows based web browser. You zoom back out and the arrows line up with the runway once more.

DaveReidUK

19th Jan 2017, 18:42

Here's a previously posted link to the 'additional' data:

https://blog.flightradar24.com/blog/wp-content/uploads/2017/01/Additional-Decoded-ADS-B-Data-TK6491.xlsx

It will open as a spreadsheet and you can see that the track is consistently about 260 degrees.

Well yes and no.

Certainly if you look at the 130 or so transmissions from the aircraft in those last 50 seconds that specify track, groundspeed and Vrate, they all show a consistent track of around 260°. After all, you would expect the aircraft to know which direction it's moving in. :O

But if you try to plot the similar number of position reports in chronological order, you will find several points where the implied track is reversed such that the aircraft appears to be moving briefly eastwards.

The reason for that isn't hard to work out for anyone who understands how FR24 and ADS-B work, and it should ring alarm bells with anyone who is thinking of trying to derive second-order parameters (not just track) from the sequence of static data points.

Unfortunately it doesn't seem to have ...

Airbubba

19th Jan 2017, 19:08

The reason for that isn't hard to work out for anyone who understands how FR24 and ADS-B work, and it should ring alarm bells with anyone who is thinking of trying to derive second-order parameters (not just track) from the sequence of static data points.

How about for someone like me who doesn't rightly understand this stuff? :confused:

Can you explain what you are saying down on my level? ;)

Are you saying jitter or quantization in the received ADS-B data is such that subsequent changes in position may indicate erroneous rates and accelerations unless some form of smoothing or filtering is done?

DaveReidUK

19th Jan 2017, 19:37

Are you saying jitter or quantization in the received ADS-B data is such that subsequent changes in position may indicate erroneous rates and accelerations unless some form of smoothing or filtering is done?

No, it's much simpler than that. :O

The data, as received from the aircraft (lat/lon, altitude, track, groundspeed, Vrate), is basically good.

So you can be pretty confident that a plot of, say, altitude or groundspeed vs position will be accurate.

The problem is that the chronological order in which FR24 lists the data doesn't necessarily match the order in which it was transmitted (those thousandth-of-a-second precision timestamps that FR24 shows are nonsense and haven't originated from the aircraft). So, for an aircraft that's on final approach on a constant track, out-of-sync position reports will typically manifest themselves as a spurious 180° change in track, as is apparent in the TK6491 data at 01:16:37 and 01:16:55, for example.

It follows that if one tries to use those unreliable timestamps to derive second-order parameters, it's asking for trouble, as in that absurd "33,000 ft/min" climb rate that several posters have quoted.

Airbubba

19th Jan 2017, 20:19

That makes sense, if the ADS-B positions are timestamped (in Unix Epoch time :)) by the FR24 servers when they are received, changes in network latency could reorder things.

jack11111

19th Jan 2017, 22:43

When receiving GPS signals you have a very accurate universal time reference. Would that not be used to stamp the ADS-B output meaning received order would not be limiting?

peekay4

20th Jan 2017, 00:14

When receiving GPS signals you have a very accurate universal time reference. Would that not be used to stamp the ADS-B output meaning received order would not be limiting?

Remember that the data stream is from multiple receivers with different (and non-constant) latencies to the server. So occasionally packets may arrive at the server in a different order from when they were originally transmitted.

It follows that if one tries to use those unreliable timestamps to derive second-order parameters, it's asking for trouble, as in that absurd "33,000 ft/min" climb rate that several posters have quoted.

It's trivial to show that the last ~ 16 packets were not affected by reordering and that the max likely timestamp error for any packet would be 0.4 seconds.

Even if we conservatively double the possible timestamp error, the bounds for vertical rate for the last few data points is still between 17,000 fpm and 30,000 fpm. Not physically realistic.

And even if we ignore the timestamps completely, we also have space constraints. The lat/long and altitude data shows the aircraft climbing at least 500 ft in altitude in about 350 ft horizontal distance (conservatively assuming 50 ft of ADS-B altitude errors due to granularity).

That means the aircraft achieved a 55 degree up vertical flight path in less than twice the aircraft's on length. Again not physically realistic.

powtough

20th Jan 2017, 00:59

Maybe they wanted to get DME information on ND MAP and deselected FMC direct to. Should have chosen raw VOR on right for switching after passing the marker.

Volume

20th Jan 2017, 06:43

Certainly the investigators have seen the engines by now and know what power they were at when they hit the ground. The one engine we have seen so far from its front end has one fragment of one single fan blade left in the hub, all the others are gone. This should indicate that at least that engine was running at full power when it hit the ground.

DaveReidUK

20th Jan 2017, 08:28

And even if we ignore the timestamps completely, we also have space constraints. The lat/long and altitude data shows the aircraft climbing at least 500 ft in altitude in about 350 ft horizontal distance (conservatively assuming 50 ft of ADS-B altitude errors due to granularity).

Not necessarily.

Remember that the data stream is from multiple receiversExactly. And not just multiple receivers, but very possibly multiple receiver types. FlightRadar24 allows feeders to use their own choice of hardware. Often when FR24 publish data, they include a "source" column so we can tell which data came from which feeder, but unfortunately they haven't in this instance.

Why does that matter? Because some ADS-B receiver/software combinations allow users to make their own pressure altitude correction by plugging a QNH value into the processing software. When the data gets to the FR24 server, it has no way of knowing whether or not this correction has been applied (let alone whether it was based on an accurate, currrent QNH) and so it gets published verbatim.

Obviously we know that many of the values in the dataset are uncorrected (because some of the heights are below the runway elevation). But to assume that all the values need to be adjusted by the same amount may well be wrong. A bit like the assumption that all the timestamps were correct, in fact. :O

Ian W

20th Jan 2017, 09:49

The timestamp on the actual ADS-B transmission from the aircraft transponder is the time that the position being sent was generated in the aircraft avionics. The timestamps are like that so out of sequence transmission receipts can be rebuilt by the air traffic management systems . I am not sure what FR24 / Flight Aware and others do with received ADS-B data from the amateur networks they use.

peekay4

20th Jan 2017, 09:56

Because some ADS-B receiver/software combinations allow users to make their own pressure altitude correction by plugging a QNH value into the processing software. When the data gets to the FR24 server, it has no way of knowing whether or not this correction has been applied (let alone whether it was based on an accurate, currrent QNH) and so it gets published verbatim.

No. Whatever altimeter setting is set for UI display does not affect the data sent to FR24.

Depending on the setup, the FR24 feeder either controls the ADS-B receiver directly (e.g., via USB) or receives ADS-B traffic via two different protocols (SBS or Beast). Both protocols simply pass transmitted Mode C altitudes, not corrected altitudes.

The timestamp on the actual ADS-B transmission from the aircraft transponder is the time that the position being sent was generated in the aircraft avionics.

There is no timestamp on the actual ADS-B transmission.

Andersin

20th Jan 2017, 10:08

Looking the last two fr24 data points, the lat/lon values seems to be ok. The logical explanation for steep climb could be a crash damage to the pitot/static port system.

Also if the altitude data would be correct, that would mean that the speed would have approximately doubled in less than 2 seconds.

ManaAdaSystem

20th Jan 2017, 10:34

Seriuosly, are you guys relying on FR24 data for the last part of the approach?
FR24 is notoriously unreliable for this phase.
Just try any random flight on FR24 into an airport (any airport apart from the major ones where coverage is presumably very good). Select 3D view and watch the appoach and landing.
Most of the time you will see an aircraft drifting left and right during the approach. Then the aircraft appears to go high on the profile. It may look like they are going around. It then will dropp (1 second) straight down onto the runway, followed by a landing roll sometimes on the runway, sometimes off the runway.
This happens 90 % of the time.
Try it.

Then imagine how this would look if somebody tried to use this data to analyze an accident.

DaveReidUK

20th Jan 2017, 11:18

Better tell the FAA quick - they are betting the ranch on ADS-B as a cornerstone of their NextGen ATM strategy. Perhaps it's something that Donald can fix as one of his first tasks ...

Then imagine how this would look if sombody tried to use this data to analyze an accident.As previously alluded to, ADS-B tracking is one of the (many) sources of data that AIBs routinely use in the course of an accident investigation.

barit1

22nd Jan 2017, 14:46

See: http://www.pprune.org/rumours-news/589633-turkish-airlines-cargo-747-crashes-kyrgyzstan.html

Magplug

22nd Jan 2017, 14:47

Read carefully again... Like the post says.... The thread has been closed

TRF4EVR

22nd Jan 2017, 15:02

Not unreasonable to ask why.

Kulverstukas

22nd Jan 2017, 15:45

BTW, there are more interesting pictures from FR24 to share:

https://cdn.aviaforum.ru/images/2017/01/822383_444a934a5d3108064be269fa3a59c0d2.png

x - distance, m

Green - flight 13/01
Red - glidepath
Blue - crash flight 16/01

https://cdn.aviaforum.ru/images/2017/01/822384_2285d656255002d373eb8c9bf5b0e5cd.png

x - distance, km

G0ULI

22nd Jan 2017, 15:45

Not so much censorship as a limit to the discussion based on the information available from local press reports and hobby reception of flight radar data. Some valid theories have been advanced as to the cause, but pointless speculating further until an official accident report appears. Seems reasonable to me.

Kulverstukas

22nd Jan 2017, 15:49

From IAC (http://mak-iac.org/rassledovaniya/boing-747-412f-tc-mcl-16-01-2017) site:

January 20, 2017
January 19, 2017 flight recorders from the Boeing 747-412 TC-MCL airline «myCARGO» (Turkey), crashed at the airport in Bishkek, January 16, 2016 was delivered to the Interstate Aviation Committee.

Received recorders have significant mechanical damage and traces of the extremely high temperatures. Conditions prevent it from reading information conventional way.

Specialists of the Interstate Aviation Committee, together with Turkish experts, the United States and the Kyrgyz Republic performed inspection, opened recorders and removed memory modules from protected storage.

The deciphering of the Flight Data data parametric recorder completed. Information read. Preliminary analysis showed that information about the accident is available.

The reconstruction of the data from voice recorder continues.

The Commission continues to work on the site of the accident. In the work of the Commission participate authorized representatives of the National Committee for Transportation Safety (the NTSB) and the United States Committee on Accident Investigation (KAIK) Turkey, as well as advisors - NTSB experts, FAA, Boeing, KAIK and airlines «myCARGO».

http://mak-iac.org/upload/iblock/bb4/TC-MCL_20-01-2017_1.jpg

http://mak-iac.org/upload/iblock/688/TC-MCL_20-01-2017_2.jpg

DaveReidUK

22nd Jan 2017, 16:17

Some valid theories have been advanced as to the cause, but pointless speculating further until an official accident report appears. Seems reasonable to me.

You could apply that argument, rightly or wrongly, to any number of post-accident threads on PPRuNe.

Clearly that has nothing to do with why this one was closed.

icarus sun

22nd Jan 2017, 16:44

MyCargo/ACT has had 2 major widebody accidents.
The B747-400f at Bishkek and an A300 in Bagram Afghanistan 2010.
This is a very poor record.

runway30

22nd Jan 2017, 16:51

I think it was an easy mistake for the media to make who wouldn't know that another airline can operate under a Turkish Airlines flight number. I should have changed the name of the thread to reflect the true position.

ExXB

22nd Jan 2017, 17:31

IIRC some governments oblige the marketing carrier to assume liability for loss and damage under international treaties (Warsaw etc./Montreal 99). Although they might try and distance themselves from the operating carrier, they likely remain liable in law for any shipments under their flight code.

PPRuNe Towers

22nd Jan 2017, 17:57

A very simple judgement,

No real news for several days.

Working pilots have abandoned the thread

It is totally overwhelmed by armchair and desk bound accident fiends

All discussion became endless posturing over nonsensical and simply wrong ADSB data points

The wrong data is assigned greater importance than the actual crash tracks and visuals because our accident boffins find data more convincing while these boffinistas tunnel in on patently wrong numbers.

Zero legal threats and zero contact from the ostensible "owners."

Therefore thread killed until there is real news from the initial formal report and the data recorders and the pilots can step in again

Rob

Kulverstukas

3rd Feb 2017, 05:13

The Interstate Aviation Committee informs that the Commission on investigation of aviation incident with the aircraft Boeing 747-412F TC-MCL completed the work on the accident site. During the field phase of the investigation, scheme the accident site was drafted with the use of unmanned aircraft. The Commission, including representatives of the National Committee for transport safety (NTSB) of the USA and the Committee on investigation (CAC) of Turkey, reviewed the elements of the aircraft, found on the site, and analyzed their damage to selected parts for future research.

Parts of the aircraft was removed from the scene and stored at the territory of airport Manas (Bishkek). Commission completed analysis of meteorological information.

Together with the specialists from the Kyrgyzstan Republic, the NTSB CAK of the US and Turkey scheduled program of flight-checking landing systems installed at the airport Manas.

The Commission continues data analysis of parametric (FDR) and voice (CVR) recorders, radar data review, tower negotiations.

...

http://mak-iac.org/upload/iblock/16e/001.jpg

http://mak-iac.org/upload/iblock/3ad/002.jpg

DaveReidUK

3rd Feb 2017, 06:35

Photos appear to have been taken looking west (top) and east (bottom) along the debris trail.

Kulverstukas

3rd Feb 2017, 08:27

peekay4

3rd Feb 2017, 14:37

Paraphrasing from the report, in line with most of the ADS-B data:

According to preliminary information, while conducting a CAT II approach at Manas,
the Boeing 747-412F TC-MCL reached the end of runway 26 at an altitude much higher
than estimated. Continuing descent, the plane flew over the entire runway and touched
down 900m from the far end of the runway 26 (at the end of runway 08) at sunset.
After touch down, the aircraft collided with a concrete fence and rolled into a village,
located 1000m away from the runway, substantially on the runway's extended centerline.

DaveReidUK

3rd Feb 2017, 15:09

After touch down, the aircraft collided with a concrete fence and rolled into a village, located 1000m away from the runway, substantially on the runway's extended centerline.I don't speak Russian, so I can't comment on the translation - but "rolled" would seem to imply that the aircraft wasn't airborne between the runway contact and the crash site.

That's hard to reconcile with Kulverstukas' second photo, which shows the houses nearest to the runway still intact.

pax britanica

3rd Feb 2017, 15:27

Rather like the Blackbushe biz jet crash last year but on a much bigger scale , too high, too fast on final resulting in touch down way to far down the runway , momentarily airborne at far end of runway but instantly crashed -in that case into cars. In there an earth bank or anything at the end of runway that could punch plane into air momentarily or perhaps a frantic haul back on stick which just got the 747 airborne to skip the boundary fence but with no energy/ momentum /speed to maintain flight and crashing again almost instantaneously

Very sad those pictures, houses remains intact and untouched on one side but the other side of the narrow street houses demolished almost completely and assume occupants killed.

Can you see the untouched car somehow escaping devastation that reaches within a few feet of it.

Airbubba

3rd Feb 2017, 16:22

Paraphrasing from the report, in line with most of the ADS-B data:

Sure looks that way. From the report, it appears that the aircraft never touched down on the runway at all, it was 900 meters past the far end of runway 26 before it contacted the ground. That would seem to rule out scenarios where a touchdown on the runway caused the autothrottles to declutch due to ground-air sensing prior to an attempted go around.

Barcli

3rd Feb 2017, 16:27

It just looks like a classic false g/s all the way down to me or am I over simplifying ?

DaveReidUK

3rd Feb 2017, 16:47

From the report, it appears that the aircraft never touched down on the runway at all, it was 900 meters past the far end of runway 26 before it contacted the ground.

Google Translate renders that part of the report, somewhat ambiguously, as "900 meters from the far end of the runway".

That could conceivably be interpreted as either 900m before the end, or 900m beyond the end.

Austrian Simon

3rd Feb 2017, 16:49

Official preliminary release (russian):

Release
(https://cdn.aviaforum.ru/images/2017/02/825327_4f62122ad9b430667690d16315354ca5.pdf)
Update (https://cdn.aviaforum.ru/images/2017/02/825328_f8562e9ff867546095f1b49fee9ac348.pdf)

Interesting to note, that these documents do not come off any official Russian government site and definitely not from the MAK/IAC website (although the PDFs claim to be released by the MAK/IAC), but an aviation forum in Russia. The documents also do not use any of the official letterheads. Official? I am anything but sure.

Edited later:

I found documents released by Rosaviatsia (CAA), not the MAK/IAC as identified in the linked PDFs. The release by Rosaviatsia, using the official letter head etc., is word by word identical to what has been created by somebody as MAK/IAC release ... So the origin of this report is Rosaviatsia.

peekay4

3rd Feb 2017, 17:25

It just looks like a classic false g/s all the way down to me or am I over simplifying ?

This doesn't fit a "classic" false g/s. A classic false g/s would still descend to the correct runway threshold, just at a (much) steeper angle. A back course g/s was suggested earlier in the thread but that explanation doesn't seem to fit the descent profile either.

That could conceivably be interpreted as either 900m before the end, or 900m beyond the end.

Well the translation if correct also included "the plane flew over the entire runway" which suggests the impact point was 900m beyond the runway end.

thf

3rd Feb 2017, 17:26

Google Translate renders that part of the report, somewhat ambiguously, as "900 meters from the far end of the runway".

That could conceivably be interpreted as either 900m before the end, or 900m beyond the end.

The Russian version is not ambiguous: 900m beyond the end. It specifically states, that it overflew the whole runway.

DaveReidUK

3rd Feb 2017, 18:19

The Russian version is not ambiguous: 900m beyond the end. It specifically states, that it overflew the whole runway.

OK, I'll bow to your linguistic ability, though I'm pretty sure that no part of "900 м от дальнего по заходу торца полосы" translates literally as "beyond".

And with a 4,200m runway, by the time you are 900m from the far end, you've already overflown almost all of it. :O

Doubtless the FDR will establish conclusively what happened and where.

grizzled

3rd Feb 2017, 20:02

DRUK...

MAK has stated that the first point of contact with any object was the concrete airport fence. That, along with no damage to approach lights, stands, localiser antennae, etc at the 08 end of the runway, suggests there was no touchdown on the runway surface.

Pali

3rd Feb 2017, 20:20

My Russian is a bit rusty but I would say that "900 м от дальнего по заходу торца полосы" means something like 900m from the western threshold of the runway.

DaveReidUK

3rd Feb 2017, 20:22

MAK has stated that the first point of contact with any object was the concrete airport fence.

No, it hasn't.

The MAK report makes a distinction between the initial contact with the ground and the collision with the fence (see post #217): "After touch down, the aircraft collided with a concrete fence"

That, along with no damage to approach lights, stands, localiser antennae, etc at the 08 end of the runway, suggests there was no touchdown on the runway surface.Not necessarily. It doesn't rule out a prior touchdown before becoming airborne again.

As I said previously, while we're waiting for the report and FDR plot everything else is simply speculation based on a relatively few published facts to date.

dignified

3rd Feb 2017, 20:36

The B744 was registered in Turkey, and under the AOC of Turkish DGCA.
Strangely enough there is no mention of the ownership of this operation? This for the purposes of insurance and responsibility for damages caused on the ground as per the Rome convention, and liabilities from the company.

I am not up to date on the number of aircraft this particular operation had, but as of year 2014 they only had two B744's based in SAW cargo hangar, a former cargo operation by Orex and Star Havayollari, pretty much a gangster operation by CEO's like Kani Kurtulus whom faded away from the industry back in year 2009 despite several attempts to re-start other similar operations in the Bakkans, Georgia and Rumania.

Ownership of this operation is based in Hainan-Island, P.R.C, which comprises several airlines in China, and some abroad as the case was with MyCargo B744 operation based in Turkey.

Several statements on this rumor network dislike the use of specific names of the crew involved in the accident.
This practice is common in China, a public execution of whom to blame for the accident; There is however no mention of the board of directors and CEO of the HNA group and their action as a result of this accident??

These information above is offered without prejudice to help the families of the crew and the relatives of the people affected by this accident, so that they can consider litigation to compensate the losses from this monopoly of HNA group based in Hainan island, China, P.R.C

grizzled

3rd Feb 2017, 20:53

DRUK

Chill mate. I said "suggests that..."

You seem to take these discussions personally and differing points of view as affronts to your own view. Yet, ironically, you mention that everything is speculation while we wait for the official facts from the investigation. So we are all speculating, including you.

Sent with smiles and an open mind

barry lloyd

3rd Feb 2017, 21:33

dignified:

According to the document labelled 'release' posted by Kulverstukas, the owners are shown as LCI Freighters One in Ireland.

https://www.lciaviation.com/fixed-wing/fleet/boeing-747-400f/

DaveReidUK

3rd Feb 2017, 21:39

So we are all speculating, including you.

Indeed we are. :O

Kulverstukas

3rd Feb 2017, 21:58

Interesting to note, that these documents do not come off any official Russian government site and definitely not from the MAK/IAC website (although the PDFs claim to be released by the MAK/IAC), but an aviation forum in Russia. The documents also do not use any of the official letterheads. Official? I am anything but sure.

Edited later:

I found documents released by Rosaviatsia (CAA), not the MAK/IAC as identified in the linked PDFs. The release by Rosaviatsia, using the official letter head etc., is word by word identical to what has been created by somebody as MAK/IAC release ... So the origin of this report is Rosaviatsia.
I newer pointed out it's MAK release, just "official". I'm not familiar with western practice of informing pilots about possible dangers before official report is published, but here Rosavia (kind of Ministry of Aviation) usually circulates such letters (in form of telegrams previously) with recommendations based on preliminary findings of investigations.

So first part is just copy of "Known facts" from MAK report and second part can lead us to possible findings of investigation committee.

Kulverstukas

3rd Feb 2017, 22:08

As I can make it into english:

Plane overflew whole length of runway and landed on the ground 900 m after the end or RWY26 (beginning of RWY8). After landing, plane crashed into concrete fence of the airport and through it rolled into the village, located 1000m from the RWY.

Kulverstukas

3rd Feb 2017, 22:15

And from interview with the Head of Investigation Committee (https://www.youtube.com/watch?v=9V-G93tMMbk):

Last communication with the Tower was weather check.

thf

3rd Feb 2017, 22:28

I think avherald.com has the translation correct ("On Feb 3rd ..."): Crash: MyCargo B744 at Bishkek on Jan 16th 2017, impacted terrain on go around (http://avherald.com/h?article=4a38d07d&opt=0)

DaveReidUK

3rd Feb 2017, 22:30

After landing, plane crashed into concrete fence of the airport and through it rolled into the village, located 1000m from the RWY.

What do you think might account for the undamaged houses in the photo you posted, between the airport and the destroyed ones ?

Kulverstukas

3rd Feb 2017, 22:38

I don't know and it doesn't fit with drafts of damage on the village map (official, issued by village administration) I posted earlier and there is visible right shift in the damage area relative to rwy.

https://cdn.aviaforum.ru/images/2017/02/825415_aaedf8970764c0a5eaa8fa3ae9d8ade8.jpg

Machinbird

3rd Feb 2017, 23:21

Plane overflew whole length of runway and landed on the ground 900 m after the end or RWY26 Would it be possible for this accident aircraft to set up an approach to the wrong end of the runway by keying in the wrong data? It wouldn't be a full ILS of course, but might use a combination of GPS and localizer data.

lomapaseo

4th Feb 2017, 00:21

Points of contact with the ground.

Just in case anybody is reading too much into the pictures and unofficial words.

The attitude of the plane makes a difference (pitch and roll) as well as the dangling parts of the plane like gear and engines. Even in the Korean event in Guam it was clear that the first contact was way upstream from where the wreckage sat in the ravine

I'm not content to conclude anything based on what's reported to-date. However I will follow with interest any speculation from herein regarding what might make a difference in the causal chain.

short bus

4th Feb 2017, 01:03

This may have been posted before but this video is from around the impact site. I found just after 5:00 to be of particular interest showing a concrete fence with sheared vegetation, what appear to be tire tracks, and the area around the red and white striped building. As a warning, note that the makeshift morgue is also shown but everything seems to be covered.

https://youtu.be/NBEJP-s7nHE

despegue

4th Feb 2017, 06:54

Regarding the possibility of setting-up a manual inserted approach into the fmc, let me give this theoretical possibility:
crew initially planned for an approach on rwy08, which is logical as this would be the preferential rwy according to current wind in the metar/atis, and had to change last minute for a setup for rwy26.
Runway and/or approach not in fmc database, manual entries in fmc. This caused the crew to be rushed.
As the aircraft showed problems with capturing ILS signals on previous sectors, which was not put in the techlog, (something that is a common occurence with ACT by the way), they followed a LNAV/VNAV approach, with a vnav path based on last point in fmc: threshold rwy08 where VNAV calculates to fly over at 50' .

This is by the way a rumour "on the ground"...

Totally unbelieveable obviously, but theoretically possible and an explanation that correlates with current information.

Kulverstukas

4th Feb 2017, 08:04

Airbubba

4th Feb 2017, 17:28

For some reason, IF date from FR24 is correct, the aircraft was flying a "phantom. ILS" around 4km. Offset to the West.
Now there is only one way I see this happening, and that would imply a total lack of procedures, and I will not put this on a public forum.

My question: would it be possible to program the FMCs to perform a LNAV/VNAV approach with RW26 as active runway, but with final descent waypoint (mistakably) threshold RW08? I could not think of a good reason to use such a construction under the prevailing conditions, so I want to emphasize, its a technical question only.

Scanelpan,

Yes, this is possible, and to be honest, I have already thought about this.
But surely no sane crew would do this...

Would it be possible for this accident aircraft to set up an approach to the wrong end of the runway by keying in the wrong data? It wouldn't be a full ILS of course, but might use a combination of GPS and localizer data.

Regarding the possibility of setting-up a manual inserted approach into the fmc, let me give this theoretical possibility:
crew initially planned for an approach on rwy08, which is logical as this would be the preferential rwy according to current wind in the metar/atis, and had to change last minute for a setup for rwy26.
Runway and/or approach not in fmc database, manual entries in fmc. This caused the crew to be rushed.

As the aircraft showed problems with capturing ILS signals on previous sectors, which was not put in the techlog, (something that is a common occurence with ACT by the way), they followed a LNAV/VNAV approach, with a vnav path based on last point in fmc: threshold rwy08 where VNAV calculates to fly over at 50' .

This is by the way a rumour "on the ground"...

Totally unbelieveable obviously, but theoretically possible and an explanation that correlates with current information.

The late runway switch scenario has set up a chain of events leading to a mishap many times in the FMS era. The 1995 American Cali crash and 2013 UPS crash at Birmingham are two examples that come to mind.

I've done the FMS drill of extending off a runway to build an advisory path for a visual landing on Boeing twins but I agree with everyone else that this would be suicidal in low vis to CAT II mins even if you did it right.

For the B-744 drivers, is it possible to select runway 08 and build a path in the wrong direction as some of the speculation implies? Doesn't the RW08 waypoint know the heading and plot a centerline on the ND? Or, can you just do an intercept to RW08 with an inbound course of 260 and a 3.0 degree path angle? Would LNAV and VNAV capture in this 'backwards' setup with a runway waypoint?

On some of the boxes I've flown with I don't think you can change the inbound course to a runway waypoint, i.e. go straight to the 'numbers', you have to do an intercept to a waypoint on the final course (e.g. RW08/-2). The idea is to prevent the path to the wrong end of the runway error on a 'homebuilt' approach.

Or, did they build an ad hoc approach using the wrong NDB?

Yes. But NDB for RWY08 is situated almost exactly where they crashed. Suppose this is just coincidence (no irony)

Kulverstukas

8th Feb 2017, 07:13

Short translation from leaked IAC preliminary report
Seems its a kind of letter sent to pilots by Rosavia or some big carrier...

1) While landing at Manas airport, rwy26 (CAT II ICAO) crew doesn't performs distance/altitude control which led to the situation when FAP was reached at 650 ft higher at 200 kts with LOC CAPTURE and G/S/ ARMED. Because of wrong height, there was no glideslope capture and a/c switched to ALT HOLD at 3400 ft.
2) At 1.5km from rwy accidental capture of false glideslope (~1 sec) happened which activated GS CAPTURE and a/c begin automatic descend parallel to glideslope
3) Exactly at this point crew doesn't evaluate situation and don't make decision that it's impossible to land safely from 3400 ft (aerodrome elevation is 2055 ft) and 1.5km distance. G/S pointer at PFD was at the bottom all the time but crew was not aware either.
4) With A/P engaged a/c overflew all rwy until decision height 100 ft where Cpt. announced GA because no visual contact with rwy. But TOGA was activated at 52 ft only.
5) While performed TOGA a/c touched ground 900 m from rwy end and 60 m to the right of the centerline with 6 "points" (?) accel
6) After bouncing a/c hit concrete fence and rolled out to the village, where separates with fuel spill and ground fire started.