Greetings Bill:> Here's a couple of questions from a non-pilot...
These are good questions, and I'm not sure that most pilots know the answers either. While reading your questions, I was fascinated that you've covered many of the related issues.
> Why the Left hand seat for the PIC ? Is it tradition - or was it a
> manufacturers choice to start with ?
As far as I know the left seat for PIC originated when multiengine aircraft came about. You may recall that most single engine aircraft had tandem configurations. When the side-by-side configuration came about, it was when larger multiengine aircraft came about although you could probably find exceptions. Your question about engine rotation direction played a part in the left seat selection.
Prop-driven aircraft in the US have a left turning tendency due to four factors and I won't get into each, but one of the bigger reasons is engine/prop rotation produces asymmetrical thrust if there's any AOA (better known as "asymmetrical disc loading"--a rotating prop behaves like a solid disc). In a multiengine aircraft without counter rotating props, the critical engine (the engine that produces the most thrust on the side furthest from the centerline) creates the largest yawing force if the other engine goes out. One of the techniques used to counter engine out yaw is to bank into the engine producing power (good engine). With props that turn clockwise when viewed from the cockpit, the critical engine is the starboard engine. So if you lost the port engine, a bank to the right would be the steeper than if the engines were reversed. Having the PIC on the left side allows the him/her to have a better view outside when the aircraft is banked to the right.
Once PIC was designated as the left seat, other issues such as left traffic became standardized (again for better visibility outside to see the airport). Then why right turns for holding patterns? The story goes that you're less likely to become disoriented in right turns from the left seat and vice versa and the natural tendency is to bank towards the hand holding the yoke when pulling back on it.
> Why is the configuration reversed in heli's ?
I suppose only Igor Sikorsky (or perhaps CopterDr too) can answer this for sure, but I was always told that it was easier to have the collective lever linkage in the middle (less parts). The cyclic linkages need to be offset from the engine. But I don't know how true it is as I've never really peered into the inner workings of a heli with mechanical linkages.
> Is it also true that helis manufactured in the US rotate in the opposite
> direction to those of European origin ?
I don't know about all of Europe, but I know Russian prop planes are opposite the US standard, and some German WWII fighters were like that as well. I don't know why. It makes sense to me to have it the way the US has it (right rudder is required to counter left turning tendencies--and most folks are right legged/right handed, so their right leg is stronger).
Hope this helps!
Ben
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