As long as you have a rotor you will have severe speed limitations.
  You perhaps can bump it up 20 MPH or so but the wave of the future
  IMHO is tilt rotor.

  The old tail sitter problems can be over come with modern electronics.

  http://www.rotaryeng.net/VTOL.html

  Paul Lamar

 I'll underscore what Paul says in that, if you really want to increase the
 speed of a VTVL craft helicopter or otherwise, you have to get rid of the
 classic rotor during horizontal flight. DARPA is already funding work in
 rotor retraction, high speed craft. There is already one patent filed on
 the
 retraction method with I'm sure many more duplications to come. The tilt
 rotor has already done this of course with many more examples showing up
 in
 UAV's.

 Any new design must exceed 250 kts cruise speed which are the already
 demonstrated speeds of the Sikorsky twin rotor X2 and Eurocopter's X3
 helicopters respectively.

 Look in the near future for UAV's with retractable rotors with or without
 tilting wings.

 IMHO this is where you want to put your creative energies.

 Cheers,

 Brian Feeney
 alaia design

I have put my creative energies into a tilt rotor type design
with unique novelty. Thats what I claimed anyway.
I had a provisional patent application but sadly the six
months expired before I could get (afford) the required
legal assistance and file a complete specification.
Not sure about the U.S.A. but there is no help for amateur
inventors in N.Z. or none that I could find anyway. We have
few aeronautical companies here and investigating this field.
S/VTOL designs border the impossble for someone like me
to fund or bring to production.

The tail sitter type would have to rate as one of the simplest
of the S/VTOL's, this being a good thing. Computer flight
assistance for me suggests an unstable design concept.
The two place tail sitter design that is linked below looks great.
Though it looks also like it would be hard for us older fella's to
get in and out of hehe. Also wondered, when perpendicular,
how well the engine rotors internal oil supply was managed.
I think there would possibly be enough centrifigal force to
evacuate the downhill rotor, and keep enough oil in the uphill
one when operating at near full rpm on take off and landing.
At an idle of 750 rpm the rotors would only see 250 rpm,
so warm up may present problems.
The centre housing would also have trouble draining the oil back
to the sump and a quantity would accumulate there. I assume a
dry sump would have to be applied to an engine tilted so, and
an oil scavenge provided for the centrehousing. Has anyone on
the list done any work on Wankels pointing skyward like this ?
Sam Watson


It is not something you want to do for long periods of time as one
could get extra wear on the bottom side housings.

I was thinking of landing tilt rotors in high winds today while driving
out to the hangar. A very difficult maneuver to say the least. The farmers
around here plant rows of trees along the edges of their fields. I am not
sure for what reason.

Then it came to me. Build a high block wall around your back yard to block
the wind during take off or landing or plant Italian cypress trees close
together. Cheaper than owning 40 acres for a runway. Walled in tilt rotor
airports could be built all over. Would cut the take off noise as well.

Speaking of landing a tilt rotor I found a device at the Autozone auto parts store
that you mount on your rear license plate. It starts beeping when you are
five feet away from something while backing up. As you get closer the rate of beeping
increases. When you get to one foot a steady tone is emitted. This is now
standard equipment on some cars and sport utes.

It also has a LED bar graph display with LED's at 5 feet, 4 feet, 3 feet, 2 feet
and on foot.

http://tinyurl.com/3ujt5sh

http://www.autozone.com/autozone/accessories/Peak-Dual-sensor-wireless-back-up-system?itemIdentifier=98968


I am going to install the sensors on the bottom of the RV4 wheel pants and test it
during landings.

I mounted the sensor on a long stick and mounted it in the van with the side door
open which extended it out about five feet. Worked like a charm at over 60 MPH
when it was five feet off the road.

If it is too close to something horizontally it gives a false indication so the
stick stuck out the side of the van for about five feet. It must have a very broad
sensing beam.

Paul Lamar