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Old 11th March 2010 | 22:36
  #7 (permalink)  
61 Lafite
 
Joined: Nov 2008
Posts: 90
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From: UK
So 61 Lafite, do you have experience of what Rotorway owners "have to worry about" or was that just a jibe ?
I'm surprised that it took 10 hours for that backlash!

But what the hell, I'll bite as it's more fun than ignoring it.

Worrying is a normal reaction to a level of risk. As risks go up, normal people worry more.

Risk is not an imminent failure or an inherent fault or by any definition an absolute measure of unsafety. It's simply a quantifiable potential future outcome on a given set of circumstances. For the avoidance of doubt, I have no doubt that Rotorways are safe and fun to fly. However, they present a higher risk.

In a Rotorway (which I haven't flown) there is low rotor inertia, like an R22 (which I have flown). With a human in the loop and less time to react to an engine failure, the risk of a bad outcome is higher if the engine fails. We all train for it, and (as here) skill and experience together can give a good outcome. Unfortunately there have been incidents where the outcome was not good and investigation showed probable cause was due to pilots allowing RPM to go too low. This risk in a Rotorway is probably comparable to an R22, but higher than an R44, Jetranger etc.

In a Rotorway, there is a potential for the aircraft to be built by one or more individuals who have not built a Rotorway before and are not necessarily LAMEs. Most other helicopters are factory built with embedded quality control by trained staff who build lots of them. The risk of a build-error in a Rotorway is higher. They *may* all be built perfectly, but the risk remains higher that an individual one isn't.

In a Rotorway, the aircraft is built to a cost, as are all aircraft. However, at a low cost, the ability to over-engineer for safety is lower than the ability to do so in a more expensive aircraft. Rotorway undoubtedly put huge efforts into making the aircraft as safe as possible, but they do not have the budget to create solutions which are as over-engineered as in larger aircraft. Thus the risk of a failure must be higher. It's arguable that higher complexity in bigger aircraft means there's more risk there, but I don't subscribe to that view. In my view, even though I'm sure every component is completely adequate for its purpose, and most aircraft will reach TBO with no problems, the risk of a failure in a Rotorway is higher.

Finally, it's a numbers risk: there are less Rotorways in the air flying less hours than many other types. As shown in this failure, !!!! happens, but the more hours flown in that type by all pilots across all the type's aircraft before you step into it, the lower the risk of the !!!! happening to you because it probably happened to someone else first and been fixed. The failed drive cog is a very good example of this risk.

Any normal person considering themselves exposed to a higher risk situation (but not an *unsafe* aircraft) will worry more. Well, I would, anyway. Doesn't mean you don't fly, you just make sure you understand the risks and worry about mitigating them (good checks and training, probably).

Does that answer your question?

Lafite?
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