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Message
Rusty,
the shortest way to all the know-how is via Perry
Mick's webpage!
A motherload of info!
Best is to contact him - this will put you a
lightyear or two ahead of the game, so you can continue where everyone else gets
tired of ducts! :))
A gyro would be a good application, as there are
only two speed-regimes:
acceleration to flight speed, flightspeed,
decceleration to land.
The gyros generally available for the
ultralight/experimental market do not have a collective control. So there is
only one trimmed speed/rpm.
You want to go faster - you climb; Go slower
- you sink.
To my knowledge there are only 2 gyros with a full
collective control - Air&Space 2 seater and the Groen (brothers)
Hawk.
Both are certified expensive
machines....
I am thinking of some way to incorporate a
collective control with the rather simple head design of the experimental gyros
- something like a Robinson helicopters tailrotor pitch change
mechanism....
It would allow to change your speed/rpm trim and it
would allow jump-take offs - pre-rotate the rotor to about 150% nominal
cruise rpm - disengage pre-rotator - raise collective to cruise position (or
even higher) - vertical take-off - inertia keeps the rotor running, but slowing
down - at about 50ft apply throttle and go flying (adjust collective for cruise
rpm).
The other way around for landing! The only thing
you could not do is hovering, like a helo!
Thomas J.
----- Original Message -----
Sent: Sunday, September 17, 2006 8:12
PM
Subject: [FlyRotary] Re: ducted fan
questions
All the GenAv duct attempts I could dig
up wound up
ditching the duct and going back to a prop, some after
significant time and
expense.
Hi
Donald,
Thanks for the
comments. I've also noticed an huge lack of examples of GA ducted fans,
and that usually tells you something important :-)
I've been led to
believe that ducted fans had some thrust advantages at
low airspeeds, but that they generally wouldn't work well at normal GA
type cruise speeds. Since a gyrocopter is a slow aircraft, that lives
for thrust, it just seems like it would possible work. On the other
hand, it's probably worth noting that there aren't any fan units out there for
Rotax engines on gyros, or pusher ultralights for that
matter.
Cheers,
Rusty
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