K Max crash Switzerland
 

Rotax of Lichtenstein lost their only machine in switzerland yesterday. Pilot seriously injured, possible engine failure or blade failure being proffed as possible causes .

Thirty five machines constructed by Kaman and this will make the sixth crash todate I believe.:ugh:

K Max
 

News flash posted by swisair if you can translate it.

http://mypage.bluewin.ch/aviationworld/heli/index.htm

... and the second in switzerland.

A94-0009
A94-0010
A94-0015
A94-0017
A94-0018
A94-0022
A94-0023
... are reported as written off

with
A94-0008 (HB-XQA)
makes eight.

I don't think that the K-MAX has a design flaw, but what do the experts think?

Just a K/Max fan and not experienced in the aircraft but I would say look at the exposure as a factor. OGE hovering, precision Long Line, tight LZs etc. Certainly a factor in Write-Off vs. Minor Damage.

I guess you'd have to look at it in terms of hours spent hovering/working over inhospitable terrain. I have no idea of the total numbers of K-Max hours flown vs wrecks and how it compares to other helicopters while engaged in the same activity. However, I suspect the K-Max spends more time in the H-V curve over nasty places than most anything else.

There are other types of helicopter who do nothing else:
KA-32, S64 Aircrane, B214B, Super Pumas, 205's in the restricted category. S61 Short etc. Do they have the same problem?

Remember that the Kmax like the Bell 204/5...UH-1B/C/D/H/K/L/M and 214 used for logging all have one engine....61/64/107/234's have two. If one can release the longline and load with a two engined machine....things get pretty nice....not so for the singles.

Imagine sitting there with the collective lever up under your armpit....180 foot longline...max weight on the line....no airspeed...no place nice to land...steep slope....and yer Donk dies.

It is not going to be a pretty sight when it is all over!

Now ol' Nick will argue that the chances of an engine failure are something like...... .000008 or something.....thus pretty rare events....but I would suggest the chance of crashing a single following an engine failure while logging following an engine failure is much closer to 1.0 .

What were the causes of the accidents?
How many were technical causes and how many human errors (I know of at least one where an inspector rolled one over on landing - not the fault of the machine - I'm sure there are more)

The causes

A94-0008 http://www.bfu.admin.ch/common/pdf/HB-XQA Prel. Report
A94-0009 http://www.bfu-web.de/berichte/98_cx010dfr.pdf Engine Failure due to fuel pump failure
A94-0010 http://www.ntsb.gov/NTSB/brief.asp?e...14X00605&key=1 Prel.Report
A94-0015 http://www.ntsb.gov/NTSB/brief.asp?e...30X01223&key=1 Corrosion fatigue within the blade retention bolt bushing(s) of the main rotor blade grip resulting in fatigue, cracking and ultimate separation of the upper grip plate. The separation of the upper blade grip plate led to a dynamic imbalance within the rotor system and the subsequent loss of all four rotor blades in flight.
A94-0017 http://www.ntsb.gov/NTSB/brief.asp?e...12X21608&key=1 The termination of power to the main rotor system as a result of the malfunction of the free-wheeling sprag clutch assembly, followed by the torsional overload separation of the engine adapter shaft. Factors include trees in the area where the emergency descent was attempted.
A94-0018 http://www.ntsb.gov/NTSB/brief.asp?e...12X19787&key=1 Accident in Austria: NTSB Brief: The pilot reportedly stated that after a loss of engine power, he jettisoned his external load and executed a forced landing. During the landing, the helicopter rolled onto its side, and the engine could still be heard running at a low RPM.
A94-0022 http://www.ntsb.gov/NTSB/brief.asp?e...11X09961&key=1 The pilot's inadvertent shutdown of the engine with the FUEL/OIL shutoff switch. Contributing to the accident were: the manufacturer's inadequate location and design of the FUEL/OIL shutoff switch; the FAA's inadequate determination of the type design's compliance with applicable airworthiness standards; and the helicopter's low altitude at the time of the power loss.
A94-0023 http://www.ntsb.gov/NTSB/brief.asp?e...11X09455&key=1 The pilot's failure to maintain control during autorotation, which resulted in an unleveled attitude touchdown, roll over, and collision with the ground.

More information about K-MAX here:
http://mypage.bluewin.ch/aviationworld/kmax/index.htm