VTOL Gyrocopter Quiz

Rotor Rooter

Dave Jackson
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[RotaryForum.com] - VTOL Gyrocopter Quiz


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The following is a half-serious, half-quiz, and perhaps half-assed, concept for providing a gyrocopter with vertical takeoff and landing abilities.

It is half-serious because it will conceptually work. It is half-quiz because this seems like a fun way to present it. The half-assed applies to the author of this post. This quiz consists of 1/ an opening statement; 2/ a daily hint and 3/ a daily request for guesses as to the essence of the concept.

Opening Statement: One theoretical means of providing jump-takeoff is to convert energy from gasoline to rotational inertia in the rotor. However, this creates two problems. One being the ability of the rotor to handle an extremely high centrifugal effect and the second being the ability of the craft to not counter-rotate when it is located on surface with low friction, such as a wet surface or grass.

Today's hint:
Carbon filament is a strong and lightweight material when subjected to tension.

Any initial guesses?

:)
 
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fly wheel

fly wheel

build a fly wheel out of carbon that stores the energy from the engine and releases it to the rotor at JTO?

Luc
 
Luc,
Part way there. ;)

2nd hint:
The craft requires more energy when taking off then when landing. The craft has more fuel when taking off then when landing.
 
3rd hint;

Carbon filament winding is used to produce very strong and light cylindrical containers. A couple of teardrop shaped containers would have minimal aerodynamic drag.
 
Cylinders are for storing air pressure, which is then used to spin up rotors.
Am already designing something similar as a trial project.:D
 
tip cylinders

tip cylinders

or the cylinders are placed at the tips of the blades - at take-off they are filled with fuel resulting in a rotor with lots of inertia - the rotor is overrotated and the inertial energy is used for vertical take-off - then the fuel is consumed during flight (can you pump the fuel out of the tip cylinders towards the central engine against so much centrifugal force?) - at landing, the rotor has enough inertia with the cylinders empty (but much much less so than at take-off) to do a zero-roll landing.

Luc
 
Luc;
More of of the way there.

5th hint;
The rotor is to be designed to handle 1/3 of the additional inertial that will be required for a fully functional jump takeoff.
 
Just stick a pair of OS 1.20 four-strokes out at the rotor tips. Or line the leading edges with 100 Cox .049 engines.
 
two rotors

two rotors

You have two co-axial counterrotating rotors: a regular one with blades (and collective) and one with just the cylinders at each end. In preparation of the jump take-off you pre-rotate the blades and pre-rotate the cylinders; for JTO you pull collective and to keep the blades rotating you let the higher inertial energy of the cylinder rotor drive the blade rotor (using reverse rotation gears) until the energy is depleted or stable pure autogyro flight is obtained; at cruising speed the cylinder rotor is slowed and stopped in the least draggy position. There is no more centrifugal force to be conquered to siphon out the fuel from the cylinders. In preparation for landing you let the cylinder rotor pickup the speed of the blade rotor and you lock both rotors together. This allows more inertial energy for a good flair at landing.

Luc
 
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Contra-rotating concept with one rotor on top and the second under the pilot,close to the ground.
The aero dynamic shaped cylinders on the lower rotor build up pressure due to centrifugal load and have a hollow section inside which act's as a ramjet.

Cita
 
fuel for thought

fuel for thought

Luc; You got it, exactly.
[RotaryForum.com] - VTOL Gyrocopter Quiz


The idea is to triple the available rotational inertia of the craft so that it can do a complete jump takeoff, at gross weight, with a margin of safety.

To achieve this, the rotor's 1/3 of total rotational inertia is offset by half of the counter-rotating inertia of 'supplemental fuel tanks'. The other half of the 'supplemental fuel tanks' inertia; (1/3 of the total inertia) is transmitted to the friction between the skids and the ground, which is no more rotational force than the rotor would impart without any 'supplemental fuel tanks'.
 
Why not just keep it simple and build a helicopter?
 
Cobra Doc. OK a helicopter it will be.

I am looking into the ability of combining; the idea on this thread, the single-bladed electric rotor idea, another previous idea, and the following new idea.

The objective is to come up with a coaxial, all-electric, single-bladed rotor, helicopter, with no teetering and no pitch control. :eek:

The new idea is to cyclically vary the velocity of the rotor blade as it rotates about the disk, This is an alternative to the conventional method of varying the pitch of the rotor blade as it rotates about the disk. In other words, to vary the blade's thrust, the air speed will be changed instead of the pitch.

The trick is going to be how to change the blade's velocity at 0.75 R from 439 fps to 674 fps and back in a single revolution.

It will be posted on a new thread entitled 'KISS', if it looks at all promising. :)
Dave
 
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