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Another Robinson crash

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Another Robinson crash

Old 8th Oct 2017, 21:46
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Copied nearly verbatim from my post on this in another thread back in July 2017...

For all you Robinson bashers, a quick search of the NTSB database shows that, for 2017 through the end of July (the last time I looked at the stat's), the following breakdown of accidents by manufacturer occurred:

Sikorsky - 2 (11 fatalities total)
Schweizer - 3
All other types - 6 (2 fatalities total)
Hughes/MD - 8 (6 fatalities total)
Airbus/Eurocopter - 9 (1 fatality total)
Bell - 25 (20 fatalities total)
Robinson - 34 (17 fatalities total)

Bell seems to be holding its own with Robinson in the accident and fatality departments, at least in the US (can't speak to worldwide). I did this sort of quick study for 2016 and Bells actually had more accidents and fatalities than Robinsons in the US. And yet they are one of the most respected makes. Should we not be flying Bell helicopters, either? Of course not.

I'm unable to find any data showing hours flown by each make, but it's easy to suspect that both Robinson and Bell are the busiest. Given that Robinsons do the bulk of the training in the US, that's a lot of hours doing high risk stuff. Similarly, it's easy to visualize that Bells are doing the bulk of other types of high risk work (long line, etc.) Busy + risky = more opportunity for accidents.

If anyone had any rate based (hour normalized) statistics for the US, by make, for a recent year (modern Robinsons with modern training, and all the latest AD's and SB's complied with, and definitely not pre-SFAR 73), I'd be very interested to see them.
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Old 9th Oct 2017, 08:23
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Originally Posted by aa777888
Copied nearly verbatim from my post on this in another thread back in July 2017...

For all you Robinson bashers, a quick search of the NTSB database shows that, for 2017 through the end of July (the last time I looked at the stat's), the following breakdown of accidents by manufacturer occurred:

Sikorsky - 2 (11 fatalities total)
Schweizer - 3
All other types - 6 (2 fatalities total)
Hughes/MD - 8 (6 fatalities total)
Airbus/Eurocopter - 9 (1 fatality total)
Bell - 25 (20 fatalities total)
Robinson - 34 (17 fatalities total)
Let's unpack this a bit.
Both Bell and Robinson had 11 Fatal accidents totalling 27 fatalities for Bell and 20 for Robbie up until 1 October.
These are global stats.

Now the Bell's have higher seating capacity with 1 accident taking 9 lives in a 412, as an example. This does skew the "facts" a little.
What is more relevant are that the Bell accidents are generally commercial in nature including rescue services and photography, a number of these are CFIT.

The Robbie accidents are more recreational or light commercial work. The majority are described as impacting terrain in VMC. The impact being a result of an unplanned/unexpected loss of altitude.

CFIT accidents you'd expect during high risk ops. Falling out the sky for no apparent reason during relatively mundane ops is something wholly different.

Robinson would always have you believe it's pilot error, that just seems a bit of a cop out. You can sing the praises of that little tin-can deathtrap but the reality is that it continues to cull pilots and and often good-ones at that.
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Old 9th Oct 2017, 08:59
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Bell ringer - it is ALL about context, simple numbers don't give the true picture as you have shown.
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Old 9th Oct 2017, 11:27
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Originally Posted by Bell_ringer
What is more relevant are that the Bell accidents are generally commercial in nature including rescue services and photography, a number of these are CFIT.

The Robbie accidents are more recreational or light commercial work. The majority are described as impacting terrain in VMC. The impact being a result of an unplanned/unexpected loss of altitude.
Bell_ringer: where can I read about the details of each one of these incidents to that I can come to these same conclusions? Is there a single database that I can enter into for this information?
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Old 9th Oct 2017, 15:07
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Bell_ringer unpacked it pretty good. The B412 prang mentioned I think was in Indonesia, pilot flew into a mountain in bad weather. A completely different scenario to Robinson helicopters falling out of 8/8ths of blue sky. I'm not sure what sort of conclusions @aa777888 might come to from closer examination of accident data, or the purpose in doing this. From my perspective, I'm perfectly happy to fly a B206, B212, B412 or any other Bell helicopter. No way would you get me in any flavour of Robinson helicopter.
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Old 9th Oct 2017, 15:08
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I fly a 44 because its all I can afford. I've been in some awfully rough air, and just slowed down. I have, however, been pretty damn scared a couple of times when a passenger has bumped the cyclic, trying to take a picture, or get to their cell phone or whatever. If I'd had a little looser grip on the pole I think I'd be dead. I wonder how many of the inexplicable smooth clear air disintegrations are due to that?
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Old 9th Oct 2017, 15:15
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Given the dual controls in Robinson helicopters are so easy to remove, why not remove them when flying said cyclic bumping passengers?
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Old 9th Oct 2017, 16:16
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They are always removed when I fly. Passengers still bump the cyclic. They also drop their damn cell phones on the emergency beacon switch.


But the question is, do people think cyclic bumping may be leading to mast bumping?
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Old 9th Oct 2017, 18:20
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Bellringer has added a useful synopsis to this ongoing debate, but I would need to see the raw data and his analytical methodology before agreeing or disagreeing

All that matters is the number of fatal accidents - the number of deaths is due to aircraft capacity and multiple other factors, but a fatal accident is an accident with an impact speed that can kill

I am not sure I care if I die in a commercial or a 'light commercial' accident. I am still dead. The important issue is was it pilot error or aircraft malfunction.

So how many fatal accidents were clearly NOT pilot error? That is all that matters, for that determines the safety or otherwise of the aircraft, not the pilot

I feel safer in a turbine, and safer still in a twin, but I cant afford more than a Robbie for much of my flying. I sit on the fence - there does seem to be an issue with mast bumping BUT is it due to failure to slow down...... in other words if I am a careful driver am I more at risk in a Robbie?

I dont think we have the evidence one way or the other
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Old 9th Oct 2017, 18:48
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Cyclic bumping

Gator,

Yes, I strongly suspect that many of the mast bumping incidents in Robinson are related to the cyclic being knocked out of the pilots hands by a passenger knocking the centre post.

It's only happened to me once, by a friends wife sat beside me trying to point a scenery... we were in the mountains on a beautiful sunny evening, so you can imagine how the accident report would have read...

Despite the common doctrine for a two finger grip for fine control movements these days the cyclic gets a somewhat firmer grip from me.

CRAN
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Old 9th Oct 2017, 19:09
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At some point in the risk/reward spectrum things start to get a little silly. Hell, why leave the ground at all?

For me it's fly what I can (barely) afford, or not fly. For most people that choice is going to come down on the side of flying.

I will be the first to agree that pistons are not as reliable as turbines, that 3 blades are better than 2, that high inertia is better than low inertia, and that bladder tanks are better than no bladder tanks. And I agree that the list of Robinson AD's and SB's tells a story. But that story is now well evolved, and other than the recent uptick in apparent, overly fast, turbulence penetrations in lightly loaded R66's, modern stat's don't seem to say that there is a dramatic problem with flying these machines if they are flown within their specified limits to any greater extent than other machines.

That said, I'd still really like to take a look at the raw data the Bell_ringer alludes to, if someone can point me at it. The FAA data I see does not cause me to draw conclusions that Robinsons "simply fall out of the sky" at any greater rate than other makes, i.e. other makes "simply fall out of the sky" as well.
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Old 9th Oct 2017, 20:14
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Cran: yep. I was in the snake river canyon with a guy who did it three times trying to take pictures. After the second time, I decided if he did it again I'd give him a ride. He didn't do it the fourth.


As you point out, the accident report would have said "loss of control due to turbulence in mountainous area".


I think there is a psychological tic at work here. We believe we can avoid CFIT, wires, clouds, and survive EOL. Just like when a guy dies of lung cancer, we all think "whew, he was a smoker, I'm not, I'll be ok"


But nobody thinks they can survive the 44 falling out of the sky for no reason. So that puts a whole different light on flying one of the things.


I think as long as you slow down in bad turbulence, they fall out of the sky because somebody bumps the damn center post. Its a lot more vulnerable than a joystick. And I feel better about flying them through that bit of psychological trickery.
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Old 10th Oct 2017, 13:29
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R66

The SFAR and associated SB and ADs have raised awareness for sure.

I’ve got to say, I hate flying our R66 one-up and low fuel. I dropped some pax the other month and headed off 15mins each way for fuel. It was a hot day, a bit thermally and I found myself pulling about 35% and flying at 90kts. I’ve spoken to blokes pulling max continuous one-up and being near VNE, but I just don’t think it’s good airmanship in that machine.

Like some others on here, RHC has allowed a cost effective introduction to rotary flight, and especially so into turbines. I love the machine and think it’s real capable. But the mast bumping issue isn’t a myth, so why take any chances?

Think I’m gonna duct tape my passengers’ arms to their sides from now on!

FF
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Old 10th Oct 2017, 13:46
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If a machine has a Vne then you should be able to operate it (with due allowance for the Density Altitude on the day using the RFM) up to that figure, without having to take special care or avoid light turbulence in case it falls apart.

If the helo is unsafe at those speeds then the certification was wrong and the Vne and Vno should be revised downwards accordingly.

Of course that doesn't make Robinsons as competitive or attractive as the opposition so doubtless much pressure was exerted on the FAA to accommodate the certification - perhaps like SAC and the S-92's very remote likelihood of oil loss from the MRGB.
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Old 10th Oct 2017, 17:48
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Originally Posted by [email protected]
If a machine has a Vne then you should be able to operate it (with due allowance for the Density Altitude on the day using the RFM) up to that figure, without having to take special care or avoid light turbulence in case it falls apart.

If the helo is unsafe at those speeds then the certification was wrong and the Vne and Vno should be revised downwards accordingly.

Of course that doesn't make Robinsons as competitive or attractive as the opposition so doubtless much pressure was exerted on the FAA to accommodate the certification - perhaps like SAC and the S-92's very remote likelihood of oil loss from the MRGB.
Yellow arc now added to ASI with mandatory reduction in VNE in turbulent conditions, but I take your point.

I hope to be in something more substantial before long, but I will steadfastly refrain from badmouthing the Robbies.

I think when first certified the inherently more pronounced risk of mast bumping in the lighter and more powerful R66 was not necessarily a known quantity.
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Old 10th Oct 2017, 18:40
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Originally Posted by FlimsyFan
I hope to be in something more substantial before long, but I will steadfastly refrain from badmouthing the Robbies.
While I am occasionally a bit trite about the Robinsons, I endeavour to be constructive.
Ultimately what you find yourself flying is not within your control and a matter of circumstance, so the debate is largely academic.
Just remain aware, and ahead, of the foibles of whichever machine you find yourself in.
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Old 10th Oct 2017, 19:07
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I have a couple of thousand hours in the R22 and maybe 700 in the R44. Recently I have found myself becoming very uncomfortable flying either of them. Not sure why.
I feel they don't help themselves by putting blade fixes on Youtube. I simply have no idea how any corporate lawyer approved that and then the latest VNE restriction placard doesn't really do anything other than give Robinson an out in a lawsuit."Oh, it must have been too windy and the pilot exceeded VNE. Prove otherwise. Thanks."
Mickey mouse fixes and nothing else.
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Old 10th Oct 2017, 19:31
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The accident rate doesnt scare me in the Robbies, it is the specific examples of high time Robbie pilots having inflight break-ups that scares the crap out of me. It is always blamed on the pilot, but when a design feature causes a great deal of pilot error, then it is the designs fault and not the pilots fault. Look at the Guimbal and compare accident rates to the Robbies. The difference for the same role is astounding.
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Old 10th Oct 2017, 20:22
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I think when first certified the inherently more pronounced risk of mast bumping in the lighter and more powerful R66 was not necessarily a known quantity.
why the hell not? It makes a laughing stock of the certification process which is supposed to ensure the aircraft is airworthy.
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Old 10th Oct 2017, 22:19
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Originally Posted by CappyJax
Look at the Guimbal and compare accident rates to the Robbies. The difference for the same role is astounding.
Where can that data be found for inspection? I'm interested in looking at it.
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