> > Steve, Are you going to design and build
> > your own helicopter rotor head?
> >
> > What do you think of this one?
> >
> > Paul Lamar ...No rotor no motor.
>
> Gee I don't see why helicopter maintenance is so pricey :)
>
> John
>
> Here is almost a complete articulated counter rotating rotor head.
> I can see why counter rotating rotor head helicopters are so
rare. I still
> haven't figured out how to move the forward swash plate yet. I
am thinking
> Blue Tooth radio controlled :) Four high speed, computer radio
controlled,> angular electric servos, one on each blade, would do
the trick.
> It would vastly simplify this and make fly by radio control a
real
> reality.
> It could also be done with a infra red optical link.
>
> Another possibility is control the swash plates with three
servos each.
> The servos would not have to be as fast.
>
> Perhaps the control rods can go into the inner shaft for the front
> rotor. About the only company in the world that could build this
is Kamov.
>
> It is also still laking the lagging and flapping hinges.
>
> I am not dumb enough to try to build one of these :)
>
> Paul Lamar
I think I read that the control input to the rotor has to lead by
about90 degrees? The top and bottom rotor then have to lead from
opposite directions.
-Jeff Martin
All,
The biggest drivers of the cost of helicopters are lawyers and the
government. One of the simplest, toughest, and most maintainable
rotorheadsis the Hiller U-12 with the servo paddles. This thing
can be maintained in
the middle of nowhere. With modern materials, this thing would be
bulletproof. You can see model helicopters flying with these
things every
day because it works and it's very cost effective. Certified
helicoptersmust be maintained by an A&P and most helicopters are
not designed to be
maintained by owner/operators and they have timed out components
that must
be replaced on an FAA approved schedule. For example the Bell Jet
Rangerhas these dog-bone looking tension straps in the hub that
must be replaced
at (I think) 800 hours and they cost around $1200 each (there are
two) and
this is NOT an afternoon job.
By the way, the control inputs to the rotor lead the rotor by 90
degreesbecause what you are doing is precessing a gyroscope. The
reality of what
you're doing when you make a control input is that you are tilting
the rotor
disc and the fuselage just follows the disc.
Steve Brazil
And by tilting the plane of rotation, you tilt the lift vector in from pure
Vert, so it
has a horizontal component.
It doesn't really matter what you fly, if it's certified then it's
expensive. I just found
out yestarday that the nose gear Hyd. cylinder needs to be replaced on the
414 I fly.
It started leaking on my last trip to Cali. It doesn't have field
maintainable seals and
is basically impossible to get fixed. Price new... $20k from cessna.. price
for a
rebuilt? $14k.. Price for a salvaged unit? $5600... for a ^%#$^ ~1" bore,
12" strk cylinder..!!
It's totally nuts regardless if the wings spin or not.. [now I'm guessing
that the fling wings
have a few more expensive components than a fixed wing.. I'm not trying to
compete
but it's all still crazy no matter how you slice it.. :-)]
Jarrett
Jarrett,
Send me a pic of your cylinder.... I was an aircraft hydraulic mechanic for
10 years. No such thing as we can't do it.
Larry
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