0578

Item 0578

OTHER: Helicopter - Inside - Side-by-Side - Electric Ultralight & UAV

Drawing:

For a larger view, click on the drawing; then click on the magnifying mouse pointer.

General Notes:

The side-by-side configuration is the most efficient (lift to horsepower) there is. This is particularly important when considering the large weight of today's electrical storage devices.

See the many Focke-Wulf Fw 61 and Fa 223 pictures of the spar arrangement in the thin German book entitled Die deutschen Hubschrauber - 1928-1945. Also see my notes on this subject.

Safety:

Motor failure will result in an automatic entry into autorotation, plus a slow descent rate and soft landing. A device to recover the rotors' inertia or a device to apply short duration torque could be incorporated. This default pitch of this device is set to that which is required for autorotation.

If the blades are good enough to take bullets in a UAV then they should be good enough to handle manned flight.

Ballistic parachute can be located on central mast above pilot.

A Thought:

If the blades and two-position elastomeric collective are factory produced, then homebuilders can purchase and build all the rest.

Fuselage:

Much of the tubing could be carbon, if there is a need to keep the weight down.

There could be a tail boom and a nose boom and cables from the two booms hold the rotor side arms and place.

There could be cables to a central mast and to the undercarriage, if necessary.

Rotor Disk and Power Specifications:

Gross Weight: 550 lbs Or less if possible.

Rotor Speed: 555 rpm.

Blade: VR-7, 8'-8" radius, 5.25" chord.

Collective Angle: 10.7º.

Total Power: 20 horsepower ~ Momentum theory; 26 horsepower ~ Blade element theory. Why the large difference?

Disk Loading: 1.16 lb / sq-ft.

For comparative power requirements between configurations see; DESIGN: UniCopter ~ Electrotor ~ Rotor

Landing Gear:

A pair of skids will probably be preferable to the tripod arraignment.

Transportability:

Rotor supporting arms would swing forward and inward. Both 2-blade rotors would have their blades pointing forward and aft; or perhaps the blade grips might be modified so that all four blades point aft.

The tail boom is detachable.

Bowden cables between the mixer box and the rotor will simplify the swinging of the rotor spars.

This gives a very collapsed configuration for storage and ground transportation.

Weight and Balance:

Was SynchroLite I ~ REPORT: Weight and Balance. Being modified for this craft

There maybe additional ideas on Weight And Balance

--------

Item:	Full Name:	Wt. Ea.	Qty	X	Y	Z	*Wt. X**
0451	Control - Flight - Assembly - Final	14.0	1	-12.0	0.0	10.0	-168.0
0581	Control - Power Train - Assembly - Final	8.0	1	7.0	0.0	15.0	56.0
0515	Electrical - Assembly - Final	10.0	1	0.0	0.0	0.0	0.0
1520?	Motor - Assembly - Final	4.2	2	0.0	x.0	xx.0	xx.0
0523	Reducer - Assembly - Final	19.8	2	0.0	0.0	x.0	x.0
0583	Equipment - Assembly - Final	1.0	1	-12.0	0.0	20.0	-12.0
0500	Fuselage - Assembly - Final	25.0	1	0.0	0.0	9.6	0.0
0375	Instrument - Assembly - Final	3.0	1	-34.0	0.0	12.0	-102.0
0521	Landing Gear - Rear - Composite Legs	3.0	2	13.0	0.0	-6.0	78.0
0692	Rotor - Assembly - Final - VR-7b - 5.25"	38.0	2	0.0	0.0	60.0	76.0
	Net Weight:	202.0
0389	Weight & Balance - Batteries ⁽¹⁾	xx.0	x	x.0	x.0	x.0	x.0
0265	Weight & Balance - Load - Pilot	230.0	1	-12.0	0.0	14.0	-2013.0
	Payload:	xx.0					-xx.0
	Total Weight:	xx.0		Total Moment:			-xx.0
				CofG from masts:			-x.xx

(1) xxx.

	Dimensions are in inches and weights are in pounds.
	Total weight is item quantity times item weight

Ultralight Category:

The weight of this craft should be below 254 lbs. In addition, with the use of independent speed control on each motor, and gyrocopter cyclic control this rotorcraft may become nearly as simple and as safer as a gyrocopter. Since the gyrocopter is excepted into Sport Plane/Pilot then there is no reason why a larger version of this helicopter cannot be eventually accepted.

Unmanned Air Vehicle (UAV):

A UAV craft provides a safe way to develop and test the craft.

Low vibration: For a camera mount this configuration should provide the least vibration. This is because there is no rotor to rotor interaction, the downwash is on a fuselage of thin tubing and there is no tail-rotor.

Sophisticated remote controls, if required, could be developed by another company.

Design:

The spine and tailboom may be horizontal and slightly higher if the ELECTROTOR ~ SloMo or the 3-blade CVJ w/ Hub Spring were implemented at some later date.

The battery packs will be separate items that will be attached at the rotors.

The in-flight mission equipment will be a separate module(s) that will attach to the spline.

Thoughts:

Lateral Static stability: Point the two disks slightly inward.

Consider using weight shifting for flight control. See musings below.

A ruddervator could be mechanically linked to the action of weight shifting.

Potential Concerns:

Motor: A failure of torque to one rotor must be matched by an immediate matched by the removal of torque to the other rotor. .

Control - Flight: The opposing torque of driving both rotors will increase the friction in the pitch and roll control bearings. This might result in high cyclical control forces.

Vibration: The thrust (Collective) is by the rpm of the rotors. This means that the fuselage etc will have to be 'tuned' so that it does not have a frequency within the operational frequency of the rotors.

Motor: Will the two motors be strong enough for any prolonged flying. They may require special cooling. Dry Ice :). What about spraying a fine mist into the motor and cool by evaporation????

There is the possibility of an asymmetrical settling with power (vortex ring state) during an autorotation.

Gyrocopter Fuselage Plans:

Plans for the Gyrobee gyrocopter less head and blades

Plans for a Hornet gyrocopter less head and blades.

Additional Information:

OTHER: Aerodynamic - Rotor Disk - Dual Configuration - Side-by-Side

OTHER: Helicopter - Inside - Side-by-Side - Electric Ultralight & UAV

Relevant Fuselage Information: SynchroLite - Fuselage

Latest revision; November 8, 2008