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Flying Lawyer
13th Sep 2006, 05:16
Stuff Co NZ report Fatal helicopter crash blamed on rotor

A fatal helicopter crash near Murchison last August was caused by an incorrectly assembled tail rotor drive shaft, a Civil Aviation Authority (CAA) investigation has concluded.

Philip Heney, 52, a father of nine, was killed when his privately owned two-seater Robinson R22 helicopter ZK-HVN crashed just 100m from his Shenandoah home, 23km southwest of Murchison last August 25.

A passenger in the helicopter, Hamish Teddy, of Wakefield, near Nelson, survived the crash with serious leg injuries.

In a CAA report released today investigators found the crash was caused by the failure of a tail rotor drive shaft that had been incorrectly assembled.
"One or more of the unsupervised and unlicensed maintenance personnel had incorrectly bolted the aft flange of the tail rotor drive shaft directly to the input yoke of the tail rotor gearbox which resulted in failure of the tail rotor drive shaft," the report said.
"The risk taking behaviour exhibited during the maintenance of ZK-HVN allowed a critical defect to be built in to the helicopter's tail rotor drive system and then allowed it to remain undetected."

Compliance with civil aviation rules and an associated advisory circular would have prevented the accident, the CAA inspector found.

Two Nelson men, aged 55 and 58, have been charged with manslaughter over the crash.
They are scheduled to appear in Nelson District Court on Thursday.

Bushbandit
13th Sep 2006, 05:48
Phillip Heney was a good man who was very respected in his district who is sadly missed by his wife and kids.
It's always the way the good guys die before there time.
Just hope the NZ justice system works better in this case than others in previous years.
RIP PHILLIP .

Gomer Pylot
13th Sep 2006, 14:44
Well, that's the sort of thing that often happens when one tries to be cheap on maintenance. He didn't know those guys were unsupervised and unlicensed?

EMS R22
14th Sep 2006, 05:29
Gomer,

Not all the personal at the company were unlicensed.Being unlicensed doesn't mean you are a crap engineer.

Do you know for a fact he was going there for mantainance because it was cheap ?

Grainger
14th Sep 2006, 08:57
. . . incorrectly bolted the aft flange of the tail rotor drive shaft directly to the input yoke of the tail rotor gearbox . . .Am I correct in understanding that this means they omitted the four-pronged flex coupling plate ?

Would this have been visible through the sight window at the back of the tailboom ?

Bronx
14th Sep 2006, 10:09
"Well, that's the sort of thing that often happens when one tries to be cheap on maintenance."

It can happen - period.

Look at the A109 crash in England when they thought it was pilot error until a second one crashed (EMS or Police?) and they found out the main UK Agusta agent fitted the scissors link the wrong way round. Back to the first one and hey - scissors link fitted the wrong way round.

rotornut
14th Sep 2006, 11:36
A terrible mistake and these guys were licensed:
http://www.tsb.gc.ca/en/reports/air/2000/a00p0077/a00p0077.asp

Grainger
14th Sep 2006, 12:12
That's a different incident, isn't it rn ?

rotornut
14th Sep 2006, 16:45
Yes, but it's part of the same theme - human error. Having been in one near catastophic incident due to negligence on the part of a licensed engineer these cases are all very relevant to me.

Grainger
14th Sep 2006, 17:00
Fair enough, rn.

Here's the link I was looking for:

http://www.caa.govt.nz/fulltext/Fatal_accidents/ZK-HVN_Fatal.pdf

Crucial part is pages 7-9. Looks like it was a bit more subtle than just missing out the flexplate. Seems the bolts were assembled incorrectly, negating the effect of the flexplate, but from the look of the diagram this would be really difficult - if not impossible - to spot during the normal Check 'A'.

noooby
15th Sep 2006, 19:54
Rotornut, that TSB accident is a very good example of 4 people missing a basic item, and it leading to a fatal accident. Why I especially applaude this report, is that it always mentions the 4 people involved that could have prevented the situation from getting worse.
Usually, if a pilot a causal factor we get: Awww pilot error accident. Poor fellah. Lets learn from this and train better for it.
Or, if a mechanic is a causal factor we get: Holy :mad: you idiot. Hang him he's costing me money!!!
Always amazes me that after 10,000 hours training a licenced mechanic, they don't get any recurring training through their careers, unless they are lucky enough to get a type course.
Would be nice if companies invested the same amount of time and effort into keeping their mechanics proficient as they spend on their pilots.
Unfortunately while the number of maintenance induced accidents stays as low as it is, this probably won't happen.
Companies only see a mchine on the ground as losing money. They don't see that a good mechanic could halve the amount of time it spends on the ground, thereby improving profit.
Back to this accident. It took me a wee while to see the difference in the drawing. Haven't worked on Robbies before. LAE should have inspected that rear coupling. As an LAE, I sure would have. They also should have queried Robinson about replacing a -1 driveshaft with a -3. If the part numbers don't match, and it isn't in the parts book, warning bells should start ringing!!!
Apologies for the long post. Accidents, and preventing them, get me wound up!!!! :}

TukTuk BoomBoom
15th Sep 2006, 20:47
I agree with Nooby, once you get an AME licence you are out of the system and left to your own devices (unless youre in a 145 organisation) . If your procedures drift off from the Rules or the MM its left to your peers to point it out.
Part 43 maintenance was a joke right from the start and so were the audits by CAA.
I will always believe it is another way to reduce the minimum requirements for aircraft maintenance and supports a lot of operators who shouldnt be in business in the first place.
There should be one standard for helicopter maintenance.

Bushbandit
16th Sep 2006, 07:55
This site always amazes me as to how many F*&KWits on here jump to conclusions without knowing the full facts whether its mechanical or pilot error .
ZK-HVN had just had new main blades, new tail rotor blades ,tail rotor gearbox and pitch links and other joints .
So before people start jumping to conclusions, how about knowing the full facts.:=

TukTuk BoomBoom
16th Sep 2006, 08:59
Bushbandit.... WTF??


Did you read the CAA report?
Werent the facts above clear enough?
When the driveshaft breaks beacause it was assembled wrong I dont think you call it pilot error.
And the developing trend, certainly in Australia, in these sort of cases is prosecution and jail time for the people responsible.
Big lesson...If youre a supervising LAME youd better have your **** together.

Helijo
16th Sep 2006, 22:28
Phil was a good bloke. hope they are hard as hell on those engineers

Bushbandit
17th Sep 2006, 00:02
Tuk Tuk
Yes i read the report about 3 months ago. And yes it was before it was released . When you get people like Gomer Pilot going on about cheap maintence that is why i have my reasons to have my say .
Yes the report was clear and hope they get there fear justice .
Bushbandit

TukTuk BoomBoom
17th Sep 2006, 03:48
I see your point Bushbandit.
The problem is anyone can set up under part 43 and sign for maintenance and unfortunately youd never know if they were any good.
The checks on the part 43 outfits are minimal, you dont even have to have a full time employee rated on the aircraft you work on..just get some guy in.
Maintenance-wise Robinsons are almost bullet proof but not fool-proof.

Why are there not more strict guidelines on staff and experience and audits for part 43 ????

sox6
17th Sep 2006, 09:52
I see that the NZ CAA investigated this fatal accident rather than TAIC. Surely not very independent? Though there is a statement:

A CAA field safety adviser had visited the maintenance organisation during the time that the maintenance was being carried out on ZK-HVN. The CAA officer discussed the issue of the absence of a full time certifying LAME with the CEO and gave him advice on the requirements in respect of direct supervision of the unlicensed personnel by the certifying LAME.


Advice seems to be at the limit of their authority as the report also explains that:

Prior to 1992, legislation required that all maintenance organisations be approved by the Director of Civil Aviation, and because of this the CAA had an active inspectorial role for. Maintenance organisations were regularly visited by the CAA inspectors to check performance against standards set out in both the company procedures manual and the existing regulations.

The legislative amendments of 1992 brought about by the ‘Swedavia McGregor report’ changed the way aircraft maintenance was regulated.

The smaller general aviation maintenance companies performing maintenance on aircraft under 5700kg, or of 9 seats or less were, and still are, no longer required to be approved. The CAA does not currently conduct scheduled inspections to measure the performance of these organisations, but has in the past conducted unscheduled ‘spot checks’.

Followed by a number of internal CAA recommendations.

noooby
19th Sep 2006, 06:50
sox6, TAIC always have the first option of conducting an investigation. Sometimes, if the accident/incident doesn't fall into their guidelines, they will decline to investigate, and pass it onto the CAA.
You'll note in the report, that it states that TAIC declined to investigate. Just because CAA are investigating, doesn't mean it won't be impartial. If the investigator takes his/her job seriously, they'll be impartial alright!!

Helijo. Pilots kill people everyday by making errors of judgement, or by blatantly breaking the rules. Coming down hard on people often has a negative affect on future investigations, as things may try to be hidden. We don't come down hard on pilots when they make mistakes that kill people, so why the engineers?? (having said that, police will try their darndest to make manslaughter charges stick. Remember Ansett Dash 8??) If dodgy parts had been knowingly used, that would be different. This seems to be a case of lack of supervision, and lack of knowledge about the aircraft type (incorrect dash number drive shaft installed, and flexplate incorrectly installed). How many hours had the engineers worked in the past week?? How many had they worked that day?? How about some duty time limitations, so that fatigue doesn't cloud their better judgement?? Oh yeah, can't do that, that would affect aircraft availability. The lax state of affairs with Part 43 rules doesn't help either.

Tuk Tuk, if you want supervising LAME's to have their sh:mad: t together, you better be prepared to pay them better money for the responsibilities that nobody seems to be willing to acknowledge they have. The situation is only going to get worse as less and less engineers take on more and more work. Have you noticed how the average age of engineers is steadily increasing??

Te_Kahu
11th Oct 2006, 03:46
Accused in Murchison helicopter-death case named

3.00pm Wednesday October 11, 2006


Name suppression has lapsed for two men facing manslaughter charges after a fatal helicopter crash near Nelson.

Ronald David Potts and John Arthur Horrell were charged after the crash at Murchison in August last year.

Police said after their arrest that the charges related to maintenance on the helicopter.

A Civil Aviation Authority report found a wrongly assembled tail rotor drive shaft caused the crash which killed pilot, Philip Heney and seriously injured his passenger.

It said one or more unsupervised and unlicensed maintenance personnel had incorrectly bolted the drive shaft.

The two men have been remanded for a pre-depositions hearing on November 13.
NEWSTALK ZB, NZHERALD STAFF