AW139 crash in Kenya
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AW139 crash in Kenya
A (brand new) AW139 operated by the Kenyan Police crashed only days after the "factory pilot" was sent home..
Four cops injured after new police helicopter crashes in Mathare | The Star, Kenya
Thats the second crash within 2 weeks-a Long Ranger crashed at Wilson Airport after an Autorotation Training went wrong (according to reports, he still had some feet to go at the end of the autorotation-unlicensed "instructor" on board, if it´s true what they say..).
Four cops injured after new police helicopter crashes in Mathare | The Star, Kenya
Thats the second crash within 2 weeks-a Long Ranger crashed at Wilson Airport after an Autorotation Training went wrong (according to reports, he still had some feet to go at the end of the autorotation-unlicensed "instructor" on board, if it´s true what they say..).
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Looking at the photos of it on the ground, the main landing gear seems to have been retracted when it landed.
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My thoughts go to the crew and I wish them a speedy recovery.
This is what I see in the video: An OGE hover at about 500ft AGL. An event that caused the aircraft to rotate approximately 45 degrees to the right. A rapid onset of vertical descent with a reversal of direction of rotation. Right hand rotation recommencing just prior to impact.
I don't think it was VRS as there was no RoD prior to the event. The rotation could conceivably have come from the fishtail effect of an engine failure but I would have expected to see a rapid nose down input from the pilot as it should be easily possible to fly out OEI from that height even at Kenyan temperatures and the RoD builds too quickly for OEI (unless the lever was down for some reason) It could conceivably have been a simultaneous double engine failure but, honestly, they only ever happen in the simulator these days. That amount of yaw, in that direction, would have led the pilots to suspect a tail drive shaft failure. My best guess here is that there was an uncommanded yaw to the right (possibly caused by a failure of tail rotor drive) that led the pilot to enter autorotation and attemp a near vertical auto from 500ft. The recommencement of rotation prior to impact probably indicates that the engines were not shut down. A difficult one to call!!
This is what I see in the video: An OGE hover at about 500ft AGL. An event that caused the aircraft to rotate approximately 45 degrees to the right. A rapid onset of vertical descent with a reversal of direction of rotation. Right hand rotation recommencing just prior to impact.
I don't think it was VRS as there was no RoD prior to the event. The rotation could conceivably have come from the fishtail effect of an engine failure but I would have expected to see a rapid nose down input from the pilot as it should be easily possible to fly out OEI from that height even at Kenyan temperatures and the RoD builds too quickly for OEI (unless the lever was down for some reason) It could conceivably have been a simultaneous double engine failure but, honestly, they only ever happen in the simulator these days. That amount of yaw, in that direction, would have led the pilots to suspect a tail drive shaft failure. My best guess here is that there was an uncommanded yaw to the right (possibly caused by a failure of tail rotor drive) that led the pilot to enter autorotation and attemp a near vertical auto from 500ft. The recommencement of rotation prior to impact probably indicates that the engines were not shut down. A difficult one to call!!
Last edited by Max Contingency; 9th Sep 2016 at 04:40.
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A double engine failure would have led to a drastic reduction in rotorspeed-especially considering that the pilots are very inexperienced.
Just a few days before, the Kenyans had sent the factory pilot home, as they considered their own pilots (according to reports each of one had less than 1000 hours total time) good enough to fly it.
It is not unlikely in this culture to run out of fuel......which would explain an engine failure.....but i still believe that it was VRS.....all it takes is a slight RoD....Kenya is at 10.000 ft PA, and sometimes even higher....
Just a few days before, the Kenyans had sent the factory pilot home, as they considered their own pilots (according to reports each of one had less than 1000 hours total time) good enough to fly it.
It is not unlikely in this culture to run out of fuel......which would explain an engine failure.....but i still believe that it was VRS.....all it takes is a slight RoD....Kenya is at 10.000 ft PA, and sometimes even higher....
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Speedy recovery Guys
Jomo Kenyatta, which is just a few km away, is at 1,624m / 5,327ft elevation.
At the moment it is HKJK 090800Z 04005KT 9999 SCT022 19/12 Q1026 NOSIG
I'm sure you can work out the PA from that, and of course the DA
hueyracer;
Kenya is at 10.000 ft PA, and sometimes even higher....
Kenya is at 10.000 ft PA, and sometimes even higher....
At the moment it is HKJK 090800Z 04005KT 9999 SCT022 19/12 Q1026 NOSIG
I'm sure you can work out the PA from that, and of course the DA
Last edited by SilsoeSid; 9th Sep 2016 at 12:20.
Rip Guys
I'm sure you can work out the PA from that, and of course the DA
Last edited by 212man; 9th Sep 2016 at 09:01.
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Looks like VRS to me. Difficult to see from any of the angles whether there was any rate of descent, but the initial right yaw would fit with a sudden application of collective to try to arrest a descent. This could have been the trigger to enter VRS, which leads to the apparent loss of yaw, and subsequently pitch & roll control as the VRS becomes fully developed.
I agree incipient VRS is not difficult to effect a recovery from, but if you consider the likely "startle" effect, and a few seconds to recognise and react, then fully blown VRS is not easy to recover from, particularly from this height.
I agree incipient VRS is not difficult to effect a recovery from, but if you consider the likely "startle" effect, and a few seconds to recognise and react, then fully blown VRS is not easy to recover from, particularly from this height.
Last edited by Non-PC Plod; 9th Sep 2016 at 09:28.
Sub 1000hr pilots in a complex type like that?
And just after an allegedly non-rated (rather derated) instructor with a stude stoofed their newly refurbed Longranger at Wilson.
Smells like a dodgy culture at the Kenyan Police Air Wing to me.
And just after an allegedly non-rated (rather derated) instructor with a stude stoofed their newly refurbed Longranger at Wilson.
Smells like a dodgy culture at the Kenyan Police Air Wing to me.
Plenty of sub 1000hr co pilots flying complicated types around the world
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You´re right-DA, not PA (typo).....standard is somewhat around 8000-9000 ft...
Wilson (from where the aircraft is launching) is even higher at almost 5600 feet....Temperatures are usually at around 26-28° (at time of accident, 26° were reported).
Lets assume the were at 1000 ft at 26°, they were just below 10.000 ft DA....
Wilson (from where the aircraft is launching) is even higher at almost 5600 feet....Temperatures are usually at around 26-28° (at time of accident, 26° were reported).
Lets assume the were at 1000 ft at 26°, they were just below 10.000 ft DA....
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You´re right-DA, not PA (typo).....standard is somewhat around 8000-9000 ft...
Wilson (from where the aircraft is launching) is even higher at almost 5600 feet....Temperatures are usually at around 26-28° (at time of accident, 26° were reported).
Lets assume the were at 1000 ft at 26°, they were just below 10.000 ft DA....
Wilson (from where the aircraft is launching) is even higher at almost 5600 feet....Temperatures are usually at around 26-28° (at time of accident, 26° were reported).
Lets assume the were at 1000 ft at 26°, they were just below 10.000 ft DA....
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I'm just impressed that Kenya has a Police air wing with a 139. When I was last there I didn't see many high speed car chases. Maybe it's used more as a transport for very self important people. Hope the crew recover well and quickly. I also found VRS quite difficult to get into, but then I didn't fly something quite so complex.
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at 7000/8000 DA that a/c doesn't make a fuss about hovering at MTOW in light winds.
Moreover, 4 pax and 3 hours endurance on a police equipped 139 makes me believe about a TOW around 6200kg at the time of the crash....if this figure is correct and considering stable hover as everybody can see I don't think VRS or neither LTE would be the cause of such disaster.
TRDSF?
T/R control binding?
Maybe coupled by wrong pilot reaction?
Just my opinion
Moreover, 4 pax and 3 hours endurance on a police equipped 139 makes me believe about a TOW around 6200kg at the time of the crash....if this figure is correct and considering stable hover as everybody can see I don't think VRS or neither LTE would be the cause of such disaster.
TRDSF?
T/R control binding?
Maybe coupled by wrong pilot reaction?
Just my opinion
Maybe it's used more as a transport for very self important people
It may have had its uses as a transport but it was well equipped with a chin mounted FLIR EO/IR [which appears to have survived] and a Trakka searchlight [which being on the port side will have been well and truly mashed] so it appears to have had a good operational intent.....
It may have had its uses as a transport but it was well equipped with a chin mounted FLIR EO/IR [which appears to have survived] and a Trakka searchlight [which being on the port side will have been well and truly mashed] so it appears to have had a good operational intent.....
Last edited by PANews; 9th Sep 2016 at 14:30. Reason: italic