It looks like the aft tail cone separated cleanly. Is there a production break at that point? Is the damper bearing located in this area?

I don't know much about the R-44, but I was wondering what would cause such a clean break in the tail boom structure as shown in the ATSB Preliminary Report.

Regards,
Grog

Some helicopters are prone to dynamic rollover, some helicopters have low inertia rotors that are unforgiving to slow reaction to engine failure, some helicopters are prone to mast-bumping, some helicopters find it easy to chop off the tail, some helicopters are very vulnerable in turbulence and some helicopters have extra speed limitations placed on them by manufacturers safety notices.

But I wonder which make manages to encompass all these flaws..............

And yet those helicopters don't crash or kill people any more often than Bell helicopters. Got the numbers to prove it. Shared them here in the link above.

I don't enjoy fighting with you...gents, but I think its important for the facts to come out so that some, poor, unsuspecting reader of these forums doesn't automatically think that Robinson helicopters are death traps, at least not without rejecting the objective evidence first, like some people do.

I'm with VF on this one. Crab summed it up quite well without actually saying what many of us here are thinking. You'll never see me in one of those flimsycopters.

Well that's highly debatable as the following graphic from this article illustrates. The graphic shows that the Robinson R44 led all major models with the highest fatal accident rate per flight flight hours for the period from 2006 to 2016 based on NTSB and FAA data.


Death rate (Fatal accidents per 100,000 flight hours)

https://cimg6.ibsrv.net/gimg/pprune....03e057da16.png

Now, there could be a variety of factors other than the helicopter itself that skews the data against the Robbies. However, given that the R44 has a nearly 60 per cent worse fatality rate than the average of the next five non-Robinson helicopters it certainly looks like the helicopter itself is a factor.

For balance, there's this article by John Zimmerman that makes a counter-argument based on fatal accidents per fleet size (as opposed to hours flown). When you look at ATSB and CASA data for Australia you see a not dissimilar outcome for fatal accidents per fleet size when comparing Robinsons with Bells; the number of fatal accidents per number of helicopters is comparable.

What is immediately apparent, however, once you dive below the headline numbers is that you do not see 'loss of control' and/or 'in-flight break-up' in the Bell column; those causes are almost uniquely attributable to Robinsons. That is surely telling.

You provided two links above - one was to a page that doesn't exist and the other was to a 206 accident investigation.

If it was a cake, you'd have changed the recipe by now.

The link worked when I posted. How it became broken I can't say. It's fixed now. The LA Times article is debatable. The fatal accident totals are accurate (they are US-only numbers). But the hours by make/model are questionable. As an owner, I've never returned a FAA flight hours survey, much like a lot of other folks, and there is no way those hours are correct. I'm impressed they were able to get the hours. I tried hard and couldn't get them from the FAA broken down by make/model. Assuming they actually got real numbers and it's not all BS. Zimmerman's article is much more realistic.

As for cake recipes, the R44 is rapidly becoming the most popular helicopter of all time. Over 6300 built to date and poised to eclipse the 7300 206's that have been built. Pretty tasty to a lot of people. That it takes more care to fly it safely I'll be the first to admit. But it's not the train wreck that everyone makes it out to be. If you fly it by the book. There are far too many who don't.

I will leave you to enjoy it. I won't be straying downwards from a 206.

If we are talking about this particular crash, the one in the thread title.
The AC gave a clear warning. The flight manual was ignored. The maintenance engineer was ignored. The helicopter eventually failed. (In a way I haven’t heard of before)

Or we can “Robinson bash/defend”, which is basically just everyone reinforcing their current view. Pretty boring stuff.

:D:D:D

Not sure that any make / model machine would treat you different, given the sequence above.

It's not the sequence that is the issue, it is the operational and safety culture that seems to be disproportionately aligned against lower-cost operators associated with this specific brand, particularly where the quality of components leaves something to be desired.

Bell Ringer

Classic thread drift. Better to post those views on the Robbie page, this one is about the crash at Broom.

The tail separating wasn't the cause of the accident, that just defined the outcome.
The accident started on the ground some time before.
While incomplete, the report doesn't paint a great picture of the operator, so it's not so much drift as a subtle yaw.

Will be interesting to know if the T/R D/S bolts were checked at the G/B flex plate. The T/R shaft has a number of rotational scores/scratches just forward for the flex plate mount as does the interior of tailcone bulkhead at the upper inspection hole. While I don't agree it was given a "clean bill of health" due to the requirement of a check flight, there are still a number of questions left unanswered at this point. And just as discussed in the Bahama Cline 139 accident, yet again we have another pilot who defies logic, plus the actions of the previous pilot, and loads his family up for a maintenance check flight. As the rotor turns....

FYI: The "clean break" is where the ATSB more than likely removed the tailcone. The accident photos show the tailcone still on the aircraft.

I find it incredulous there was no maintenance assessment flight after the maintenance was conducted. Only a ground run was performed.

Link to photo for convenience: https://www.abc.net.au/cm/rimage/124...xlarge.jpg?v=3


https://cimg7.ibsrv.net/gimg/pprune....f759f117be.jpg

Regarding Robinson statistics, one thing to keep in mind is the vast majority of private helicopter owners own a R44, with most of the remainder owning a R22. The others, especially all of the turbines, are almost entirely owned and operated commercially.

Thanks for that photograph: it certainly gives a bit more information on the crash than just photos of various bits. It looks like the helicopter hit on its right side while yawing to the left, yet the Robinson rotor system as viewed from above rotates counter-clockwise (as do most American designs), which upon loss of tail rotor authority would induce a yaw to the right. Or am I missing something again? Was the tail rotor drive train damage pre or post impact?

Regards,
Grog

Have you read the report? It clearly states the afte tail cone, TGB and empennage detached during departure, the aircraft descended yawing rapidly to the right, and impacted on its right side.