Kalitta B742 prang at Bogota on Jul 7th 2008: final report available

[KiloMikePapa]

Crash: Kalitta B742 at Bogota on Jul 7th 2008, engine fire, impacted a farm house (http://www.avherald.com/h?article=40950475/0011&opt=0)

Kalitta drivers seem to have a special guardian angel...and it seems they need him/her (Bogota, Brussels) ;)

[punkalouver]

Now I can say that I have heard of an accident with multiple, unrelated mechanical engine failures. Also at night, at high density altitude, in mountains.

One has to wonder about the quality of the engine maintenance.

[punkalouver]

Crash: Kalitta B742 at Bogota on Jul 7th 2008, engine fire, impacted a farm house




By Simon Hradecky, created Sunday, Jan 1st 2012 13:13Z, last updated Sunday, Jan 1st 2012 13:13Z

The Colombian Grupo de Investigacion de Accidentes (CGIA) released their final report in Spanish concluding the probable cause of the accident was:

The inability of the stricken aircraft to sustain flight after the loss of power from two engines.

Contributing Factors were:

- a non-recoverable surge of engine #4 during rotation resulting in the loss of engine power, the combined effects of an inefficient high pressure turbine, excessive slack space at the tips of the blades, reduced chord and leading edges of the fan blades and the high altitude contributed to the engine failure.

- an undetermined anomaly in engine #1 which manifested itsself in engine surges and resulted in the loss of engine power. The failure to maintain proper minimum aircraft speed during climb out and the resulting use of emergency extra power exposed the anomaly leading to the engine failure.

The CGIA stated in their findings:

All four engines were working normally during takeoff roll. During rotation for takeoff engine #4 (outboard right) suffered a surge that did not recover by itsself. The landing gear was selected up about 15 seconds after the engine failure and completed 22 seconds later with all gear up and all gear doors closed. The crew did not take immediate action to correct the engine surge, nor were they required to do by standard operating procedures as the aircraft had not yet reached minimum safe altitude of 800 feet AGL. Flaps were not retracted/reduced as well as the aircraft had not yet reached minimum safe altitude and had not reached indicated airspeeds according to the one engine inoperative flaps schedule. While climbing out on three engines the captain did not maintain V2 or above, the angle of attack continuously increased until the activation of the stick shaker, only by then the captain lowered the nose of the aircraft which accelerated but descended down to 400 feet AGL again. The captain again increased the pitch angle of the aircraft again until activation of the stick shaker at which point he firewalled the thrust levers producing a state of overboost on the remaining three engines in an effort to increase speed and altitude. In the next 5 seconds the GPWS issued four "Don't sink" aural alerts, the speed reached V2 and the altitude increased by 100 feet in the 12 seconds after firewalling the thrust levers. About 20 seconds after the thrust levers were firewalled engine #1 lost its power leaving the aircraft in a state where it could not sustain flight in its present configuration. Engine #3 continued to operate normally while engine #2 suffered and recovered from repeated engine surges. At impact engine #4 was still turning at low speed.

The CGIA also stated in their findings that environmental considerations like altitude, darkness, rising terrain around the aerodrome, may have affected to the outcome.

Analysis of the aircraft performance showed the climb performance expected for a Boeing 747-200 with one or two engines inoperative was better than the actual performance shown by N714CK. The reasons for the degraded performance by N714CK could not be clearly identified with the data available.

Aerodynamic assessment and simulator checks showed the Boeing 747-200 with JT9D engines would be able to climb about 200 feet/min faster in average than the accident aircraft did over a period of 3 minutes.

The accident aircraft was capable to sustain a climb rate of 750 feet/min with one engine inoperative provided it was kept at or above V2.

Engineers determined that the high pressure turbine of engine #4, that had been installed during the last work shop visit in January 2008, was inefficient due to too large a blade tip clearance, the reduced chord and wear of leading edges of fan blades resulting in a loss of engine power estimated at 5.8%. The high altitude impaired stability and operatibility of the engine.

Engine #1 suffered a failure of the low pressure turbine which resulted in ejection of engine parts through the engine exhaust. The failure originated in the third stage of the LPT, engineers believe the failure started with the loss of a number of guide vanes or the loss of a large piece of outside air seal due to thermal damage. Although an overboost condition existed outside regular engine operation range the application of such engine power for a short period of time should not have caused an engine failure. The exact cause of the engine failure could not be determined.

The CGIA reported that the captain (51, ATPL, 8,874 hours total, 2,874 hours on type) was pilot flying, the first officer (49, ATPL, 11,373 hours total, 2,853 hours on type) was pilot monitoring, the flight engineer (59) had a total flying experience of 10,665 hours and 2,665 hours on type.

the aircraft was configured for takeoff with flaps at 10 degrees (the flaps remaining in that position until impact) with the engines at EPR between 1.69 and 1.72, when it accelerated through Vr (152 knots) and rotation was initiated. While the aircraft rotated the pitch went through 13 degrees nose up and the airspeed had already exceeded V2 (162 KIAS) when engine #4 lost power, the engine rolling down from about 1.7 EPR to 1.0 EPR within 2-3 seconds, the engine surged 4 times during that time. The attitude of the aircraft increased to 17 degrees nose up and remained there between 16 and 17 degrees, the indicated airspeed began to decrease from 165 KIAS (V2+3) to 155 KIAS (V2-7), the aircraft climbed to 300 feet AGL. The cockpit voice recorder did not record a "Gear up" command, however recorded the sound of gear retracting 14 seconds after engine #4 lost power.

The indicated airspeed decreased further to 150 KIAS while the aircraft initiated a right turn according to the special departure procedure with an engine inoperative.

The aircraft reached 450 feet AGL when the stick shaker activated. Within 2 seconds the attitude reduced to 11 degrees nose up and the speed began to increase reaching 158 KIAS, the aircraft descended through 400 feet AGL, the landing gear had completely retracted by then. When the captain attempted to increase the pitch attitude to 13.5 degrees nose up again, the stick shaker activated again, 2 seconds later the EPRs of the remaining three engines increased by 0.08 reaching overboost condition, 5 seconds later the GPWS alerted "Don't sink!" four times, the speed reached V2 again and the aircraft began to climb. About 12 seconds after firewalling the engines, the aircraft had climbed by about 100 feet at that point, the aircraft reached a stable climb with the pitch attitude between 12 and 15 degrees. 8 seconds later, 20 seconds after firewalling the engines, at 162 KIAS and 600 feet AGL the EPR of engine #1 decreased from about 1.75 to 1.0 over about 2-3 seconds, the EPRs of engine #2 and #3 reduced to their takeoff settings (before firewalling the engines). The aircraft peaked at 750 feet AGL and began to descend again at 158 KIAS.

The crew declared emergency reporting they were dumping fuel.

Engine #2 at that point suffered a rapid decline of EPR and recovery of EPR for five times, each lasting for about 2-3 seconds, the surges happening at 87 seconds, 33 seconds, 13 and 3 seconds before impact. Multiple "Don't sink", "Too Low Terrain", "Too Low Gear" GPWS alarms sounded until impact.

The aircraft struck a house killing the two occupants of the house, the aircraft was airborne for 3 minutes and 15 seconds.

Two people on the ground were killed, five crew received serious and three crew minor injuries.

The aircraft had accumulated 90,613 hours total, 20,180 hours from last general repair/overhaul, presumably last overhaul), engine #1 a total of 61,516 hours (1,021 hours DURG), engine #2 a total of 85,183 hours (1,021 hours from last general repair/overhaul), engine #3 a total of 94,521 hours (1021 hours from last general repair/overhaul) and engine #4 81,690 hours total (1021 hours from last general repair/overhaul).

[Time Traveller]

Now I can say that I have heard of an accident with multiple, unrelated mechanical engine failures

All the engines were firewalled - I'm no expert on the classic, but I dont think that will do them much good.

[tom744]

Well I'm not an expert on the classic too, I fly the -400.......but before I either stall the plane or hit the ground I would certainly firewall them

[L-38]

Would like to know how well the surviving crew has recovered. Are any of them flying today?

[D-LZ 126]

Wonder how many more folks will die so Connie (along with other scumbags) can save a few buxx on MX?

FAA is all over this of course <yeah, right>....:mad:

[Wunwing]

I have a fair bit of time on P&W B747s and certainly would and have firewalled them. Why wouldn't you if you were about to hit the ground?

Wunwing

[Time Traveller]

Wunwing - yes!

But if I read it correctly, if the climb out had been at V2, then there would have been no need to firewall the engines. Maybe exacerbated by maintainence issues, the firewalling was counterproductive as it probably caused eng 1 to fail, and did cause eng 2 to fail/surge, but maybe the writing was on the wall by then (descending at 400' with the stickshaker going) so there was nothing to be lost by firewalling them. Certainly, every type I have flown has ultimate overboost protection (not so, the classic?), so the instinct is generally a good one, when its all going horribly wrong.

[grounded27]

But if I read it correctly, if the climb out had been at V2, then there would have been no need to firewall the engines. Maybe exacerbated by maintainence issues, the firewalling was counterproductive as it probably caused eng 1 to fail, and did cause eng 2 to fail/surge, but maybe the writing was on the wall by then (descending at 400' with the stickshaker going) so there was nothing to be lost by firewalling them. Certainly, every type I have flown has ultimate overboost protection (not so, the classic?), so the instinct is generally a good one, when its all going horribly wrong.

No overboost protection (common sense and a F/E) That JT9 is a beast, a stall is not something to cringe at she normally recovers nicely. All should have been up to speed by v1. #4 engine turbine failure. Suspect possibly the pitch change with advancement with thin air contributed greatly to the #2 engine coughing, it could have had bleed issues that contributed as well. Essentially they were relying on 2 engines to climb on at greater than 8300 feet ASL.

It looks like they took off 31R, I do not remember terrain being a big issue this heading, 13 with an engine out would put you into a hillside. The crew were lucky the wind was blowing in their favor.

The rock and a hard place bit here was having a stick shaker at 400'agl and pitching up.

[Junkflyer]

Having flown with the particular captain and fe on numerous occasions I can testify to their high degree of talent, experience and knowledge on the 74. Having flown the same airplane can also say I did like that particular one, but it could feel a little pitch sensitive at max gross. The report leaves out numerous factors particularly actual or documented weight, cg, crew duty, etc. South American outfits aren't known to be accurate on their weights.
What the "experts" flew in the sim has very little in common with real life. An o'dark thirty departure in high altitude in mountainous terrain is challenging enough on the best day. Realistically this was about the best outcome possible.

[zerozero]

Analysis of the aircraft performance showed the climb performance expected for a Boeing 747-200 with one or two engines inoperative was better than the actual performance shown by N714CK. The reasons for the degraded performance by N714CK could not be clearly identified with the data available.

Aerodynamic assessment and simulator checks showed the Boeing 747-200 with JT9D engines would be able to climb about 200 feet/min faster in average than the accident aircraft did over a period of 3 minutes.

The accident aircraft was capable to sustain a climb rate of 750 feet/min with one engine inoperative provided it was kept at or above V2.

Engineers determined that the high pressure turbine of engine #4, that had been installed during the last work shop visit in January 2008, was inefficient due to too large a blade tip clearance, the reduced chord and wear of leading edges of fan blades resulting in a loss of engine power estimated at 5.8%. The high altitude impaired stability and operatibility of the engine.

We really need to read between the lines on this one.

--Worn out engines, not producing rated thrust and no tolerance of overboost even for a short period.

--High altitude (pretty obvious).

--Questionable load (lots of anecdotes about being overloaded).

Recipe for disaster.

The fact the airplane flew as long as it did is a testament to the skill of the crew.

[punkalouver]

It really does show how important it is to maintain V2 in such a situation. Not easy, and no doubt many would have would have had difficulty as well. But it still does show how important very precise flying can be under certain rare occasions.

[TowerDog]

It really does show how important it is to maintain V2 in such a situation.

True, but we don't know what their VSI and radar altimeter ws reading:

If they were just about to hit terrain, then there is no choice but to pitch up and to firewall the engines.

In general the JT9 engines can be "overboosted" or firewalled for a few minuttes without coming apart, but if a certain shop did cheap overhauls on the engines then all bets are off.

I have flown the same B-747-200 planes (but different company) with engines overhauled by the same shop many times out of Bogota at night with the same kind of cargo. (Probably over loaded)
Had compressor stalls numeorus times just after take off and it scared the crap out of me..It lights up the night sky followed by loud booms and the EGT going up and EPR down.

[Earl]

I think FAA has a credibility issue starting with the new Flight duty time limitations, that restrict Pax flights but not cargo ones as they claim too expensive.
One of the majors, cargo filed a law suit on this already.
Ones on the ground died here.
A departure over a major city anywhere would have much greater fatalities.

[grounded27]

I have personally been on 2 flights in an MD-11 out of SCEL for KMIA where we were forced to land in the islands for fuel, after this happening a few times we demanded the client weigh the pallets in Miami, I was told we were about 30k lbs overweight.

[punkalouver]

True, but we don't know what their VSI and radar altimeter ws reading:

If they were just about to hit terrain, then there is no choice but to pitch up and to firewall the engines.



Actually, the report says 450 feet AGL was reached so there must have been some positive climb rate as speed bled off. Not sure if that terrain is level with the airport. Pitching up significantly above an attitude for V2 would likely increase drag quite a bit.

[Willit Run]

The next time you guys are in the sim in a 747, set the box up at these weights and altitude, if you can, get your speeds set, and then add another 40,000 pounds with the previous speeds set, and see how you do: shuck one engine at rotation, another 30 seconds later, and then pull the 3rd one back to about 50% and see what happens? Come back here and tell us how you did,

[Junkflyer]

Jumpseat: Before Sully & Skiles | Flying Magazine | The World (http://www.flyingmag.com/pilots-places/pilots-adventures-more/jumpseat-sully-skiles)

[punkalouver]

Thanks for the article. I remember reading it a few months ago. Some lessons to be learned about seat belts as a facial injury happened due to the crotch belt not being fastned. Have to admit that I have been guilty of the same.

One guy was paralyzed because he unfastened his seatbelt when upside down. Have heard of injuries in other accidents when doing the same. Soething to consider if ever in the same situation and if there is an alternative thing to do.

[16down2togo]

Like tom744 said it quite eloquently,
if you ever took a 747 of BOG yourself and one engine fails!!!
You will shove in whatever you have to pull it out of the dirt,
whatever Mr. sea lvl first officer might know. Good job gentlemen, tragic outcome, salute you,
RGDS

[punkalouver]

This is an interesting statement from the report as posted earlier...

"The accident aircraft was capable to sustain a climb rate of 750 feet/min with one engine inoperative provided it was kept at or above V2."

[grounded27]

.............delete

[Junkflyer]

I don't think that applies to an airplane and engines with 90,000 hours. I'm sure fresh out of the factory it is capable. Also the actual weight of the aircraft will never be known

[punkalouver]

Even if the engines are not putting out as much power or the aircraft is heavier than normal, flying at V2 should give better performance than pitching up to stickshaker speed. Instead the airspeed got down to V2 minus twelve knots with a turn initiated.


Might very well have happened to me as well, so a good reminder of its importance next time I fly.

I'm curious to know what the climb limit weight was that night(assuming that it was the limiting factor).

[JammedStab]

For interest sake concerning engines.....

Here is an excerpt from an old 747 accident report that crashed in Nairobi on a reduced thrust takeoff with LED's retracted. Airport elevation 5,100 feet, temperature 16°C. JT-9D-7A. It talks about the effects of increasing power to full throttle.

"The EGT redline limit would be exceeded by 30°F. No other parameter limits would be exceeded and all engine components would survive in excess of five minutes."

Of course I assume that is for properly maintained engines. The Colombia plane had -7Q engines and a different density altitude.