I tried flying my Spacewalker again the othe day in the dead calm. I had the tilt back angle set at about 3*, I think I'll change it to about 8* It looked like it was just about to lift when I ran out of runway, which BTW was over a hill almost out of sight, just the rotor visible and tore the landing gear out. I'm taking this opportunity to change to wider track landing gear. The old set was 16" wide, the new set is 24" wide and slightly taller. Bigger wheels also may help so I put on 4.5" up from 4.0", the new ones are Dave Brown Lites.

Now the question that's bothered me for a while now. Why does everyone claim you need a breeze to takeoff?

In Florida I saw Phil takeoff down wind with his twin rotor, and on my second attempt at taking off the cross wind got me and turned the gyro downwind, before I could throttle back I and one other guy thought it had taken off.

Hi Rich,

The reason that I can takeoff down wind is to due to the blade design. However, if you have the SG6042 blade profile you can also take off without any wind. I do it all the time with that profile. I learned this from Hal deBolt. Put a prop spinner on the top of the rotor and use a variable speed electric drill and pre spin the rotor. I would not set the rotor head incidence more than 5 or 6 degrees as when those blades comes up to speed it could flip you over back-wards. I start spinning slow and then increase up to the maximum speed of the drill and give full throttle. It's best for the first few times to have someone else pre-spin the blades and then you can concentrate on flying. I suspect you will be off the ground in less than 20 feet. Good luck.

Phil

Hi Rich,

>>>...Why does everyone claim you need a breeze to takeoff?...<<<

Most of us flying toy autogyros say we need "autorotational rpm" before takeoff. Like Phil says, you can generate autorotational rpm using some form of pre-rotation device. Or, you can utilize the oncoming breeze and a very slow forward taxi speed to facilitate the acceleration into full auto.

The big mistake most of us make is trying to "force a takeoff" by taxiing way too fast almost like a "starch wing" takeoff, erroneously thinking (in the case of a gyro with little or no negative blade pitch) that we can increase rotor rpm by "going faster". (How many smoking holes in the desert have I dug proving the foolishness of this thinking! <G>)

In the case of the toy autogyro--especially large ones, we must find patience to allow the mass of those blades to "fly" into full autorotational rpm. On all our designs--especially noticeable with the Kellett--if you'll hold half to full "down" elevator while you are patiently waiting for the breeze to spin you up, the tail will rise when autorotative lift is finally generated. This is the signal to the pilot that it is finally "OK" to smoothly advance the throttle. Cool!

Steve

I agree with Steve, and that part of the pleasure from flying gyros is actually watching the rotor come up to speed, the tail left, and up it goes. Our flying field has only an East/West runway and many times we have a light breeze from the North/South which makes it necessary for a quick launch across a grass strip, the reason for using the pre-spin rotor. Another trick that I have used for dual rotors, is to wind about 20 ft of string attached to a spool on the rotor hubs and stake the strings to the ground. Go full throttle and the gyro almost hops off the ground. I though I was the originator of that idea but I have since found others have done the same. It's still neat to watch.

Phil

I recall reading that the idea of using a cable to pre spin the rotor was tried on a full size autogyro! It seems the cable was staked to the ground and the gyro taxied away smartly. Worked pretty good except when the cable released from the rotor it had so much tension it snaked back and sliced off the rudder and vertical fin! Must have made for an interesting short flight!

Juan de la Cierva, as early as 1923, used a rope tied to a real live horse to pre-rotate a "C.4" autogyro. (The autogyro remained stationary and the horse pulled the rope hooked to a spindle atop the rotor...or was it the other way around...?)

Steve T.

Hi Guys,

I like the idea of the horse. I was successful in getting the dual rotor to pre-spin using lines staked to the ground, but not on the first try. Because of the incidence in the rotor head I had to run the lines through an eye hook mounted on the horizontal stab so it wouldn't get tangled in the rotor blades. However, when the line came off the spool it sometimes wrap around the eye hook and everything came to a very quick halt. Thanks for the info. I didn't realize others had similar problems.

Phil

Hi Rich.
Seems you are learning, even if a bit the hard way!
Persistance is the key, each leson learned is a step forward.
We all can help but first you must find the need. OK?
You can take an airplane off with any reasonable wind direction
but experince has taught into wind best.
Wind velocity can be deducted from needed air speed.
Into a wind, that wind is same as the airstream in flight, thus it is
passing the wing and creating some lift.
Have you noted with a plane that in a strong wind the craft takes
off with no run, leaps into the air? The wind-airstream is creating the lift the calm air take off run to needed speed does.
Giros are no different from airplanes take off wise. The rotor is
simply rotating wings instead of a fixed wing.
Both an airplane and an autogiro can take off up wind or down wind. The need is to get to take off speed with a plane, rotor rpm
with a Giro. Obvious that going down wind the craft must reach
a speed that when minus the wind speed number is the speed
required in calm air. Take of speed must be higher than the other
two ways.
Giros have a short coming which is not as serious with airplanes.
When a Giro is moving in a cross wind the wind gets under the
rotor tending to force the windward side up.At lift off this is usually a major problem,. At lift off the forces are in equalibrium
any outside force (cross wind) easily overcomes them.
Thus the word is NEVER take a Giro off except into the wind,
can be up or down, NOT from a side.
A smart operation is it is OK to taxi a plane to the runway and go
but not a Giro. You take the Giro to the runway, check wind direction with a hanky and point the Giro directly into the wind.
That simple trick saves a zillion rotor blades!
Full scale Autogiros and now Giroplanes all saw the worth of the
pre-spin ability. After several aborted take offs(read busted blades)I realized the worth also and gave it thought.
It seemed to me that a rotor is much like a large propeller. If we
can wind up a engine prop with a starter and a prop spinner why
not a rotor? Simplixity is most often the solution to evils.
My size rotor seems to autirotate at about 450 rpm, your larger one probably a bit slower. Check RPM in a wind with a tach.
I found my engine starter would only bring rotor to about 250 rpm. Solution was a B&D drill motor rated at 700 rpm. The rotor
loads it pretty heavily so I only get 400 rotor rpm but that is close
enough to produce a short take off run. Understand, the shorter
the run the less oportunity for a tip over and abort.
Can say this, since using prespin I have not had an abort, probably over a hundred take offs.
Reaching the spinner may be a problem with your rotor. At one time I had a similiar one, answer was academic. I lashed an extension onto the drill handle
Hope this answers some of your questions.
Above all don't give up the ship, you have the potential for great
times and fun!

Hal deBolt

me again Rich,
Should have said: you are concerned with settings, it's called
force arrangement with airplanes.
Know this: My Giro V craft has performed flawlessly for over 3
years now, many. many flights. wish could say same for the pilot!
To do that it must be a DGA, damn good aircraft in Benny Howard's
words.
Point is the Giro V was reported in detail in the 2/2000 RCM. All
needed facts and ranifications were given.
Bet here is if you used those exact parameters and way of doing
your Giro would be a ***** cat to use.
OK?

Hal deBolt questions? [email protected]