OTHER: Helicopter - Inside - Single Rotor - Tip-Jet (pinwheel) and Enhanced Flight-Control

• To provide enhanced flight-control authority.
• To eliminate the tail-rotor.

• No tail-rotor because the torque is produced and consumed within the main rotor assembly.
• The craft has significantly greater controllability due to the addition of a moment at the rotor; see below;

Principal Assemblies:

• Rotor:
• Information related to Gyrobee rotor: All Electric Backpack (PAV) ~ Gyrobee
• Diameter = 25 ft.; Speed = 325 RRPM; Circumference = 78.6 ft; Tip speed = 425 ft/sec.
• Mach1 = 1,087 ft/sec. Use for calculations Mach0.95 = 1,033 ft/sec

• Reference: SynchroLite ~ Rotor - Hub - 2-blade Teetering
• Reference: All Electric Backpack (PAV)
• Have Delta3?

• Power (Tip-jet) (pinwheel):
• Tip-jet (Preasure Jet)
• Pegasus helicopters, Video
• PPRuNe Thread ~ 'No tail rotor, no tail boom, no H-V worries...Pegasus helicopter'
• Rotary Wing Thread ~ 'Tip Jet Helicopters', ' Nice tip jets helicopter' Nice tip jets helicopter
• Starting the Device:
• Solid fuel plugs c/w oxidant that blocks the inlet on each nozzle. As the solid propellants burn the pinwheel will get up to speed while at the same time the inlet port will be becoming free and normal combustion can take place. I wonder.

• Reducer:
• Planetary: 3-stage, approximately 30:1 ratio.
• The gearbox must be anchored to the stationary mast.

• Gyroscopic Precession Control:
• Reference: Electrotor - Plus

• Control - Flight:
• A/ Control rods inside mast:
• Dennis L Fetters US patent 5163815
• Agusto U Cicare US patent 5165854
• Rehm N Rehm US patent 5826822
• The inner tube control system also has variants used by Enstrom, as well as Cessna/Seibel.
• B/ Overhead Spider Control:
• Could the gimbal be located at the same elevation as the gearbox thereby allowing the sun gear(s) to have a smaller diameter?

• Fuel Tank:
• Located in fuselage or backpack
• In an emergency the tank could be dropped, thereby reducing the mass of the craft and removing the risk of fire.

• Configuration:

• To provide additional cyclic control in an tip-jet powered rotorcraft that has 2-blade teetering rotor(s).
• The primary source of the additional control power comes from the inclusion of Hub Springs, (or the alternatively Offset Teetering Hinges), in the rotorhub. Each of these two devices creates a sinusoidal two-per-rev moment (vibration).
• To minimize the vibration a second device, the tip-jet rotor with short arms, is also included. It consists of a Control Moment Gyroscope, which incorporates the pair of tip-jets that drives the craft's main rotor through an internal gearbox.
• The Control Moment Gyroscope also creates a sinusoidal two-per-rev moments. However, it's moments are nearly 90º offset from the two-per-rev moments created by the Hub Springs, (or the alternative Offset Teetering Hinges). [How the 90º offset in phase is achieved.]
• The four sinusoidal moments per rotor revolution combine to reduce vibration when off-center cyclic is applied; while at the same time providing greater control of a rotorcraft with teetering rotor(s), particularly during a condition of zero-gravity.

• At a tip-jet rotational speed of 16,500 RPM, and a tip-jet speed of M1 (65,250 fpm) the tip-jet arm will be 7.5"
• Now what will the rotational inertia's of the main rotor and of the tip-jet rotor be? Note that the gears will add to the inertia.
• This tip-jet rotor will have to look more like a disk of approximately 14" OD and 1" thick, with exhaust vents around the circumference.
• This gives a phase differential of 3º off of normal to the span of the blades.
• If a 6º differential was acceptable, the rotational speed of the tip-jet could be slower, and/or the tip-jet arm could be longer, and/or the mass could be changed..

• The flight controls are located inside the mast to not interfere with the tip-jet rotor.
• During forward flight; consider the possibility reducing the thrust of the pinwheel vents on the retreating side and increasing the thrust of the vents on the advancing side. This should improve the efficiency by not have a thrust that opposes the craft's direction of travel. There will likely be a problem if the thrust of the vents has a vertical component.

• The operation of this rotor is based on the same principals as the ElectrotorPlus.
• Tip-Jet Rotor Helicopters
• Tip-jet Rotorcraft

• US patents;
• 7,198,223 ~ Ultralight coaxial rotor aircraft ~ Totally irrelevant.

• Pulse-jet ~ compression is low therefore propulsion is low.
• Ram-jet is more efficient than Pulse-jet.
• 2:1. Thrust to tip-speed
• Free piston motors ~ Moteurs a pistons liberes.mht on E-drive (stick)
• Efficiency ~ TipJetHelicopter.xls

• How to transmit torque from the high rpm pinwheel to the low rpm rotor without creating a yaw in the fuselage and/or an excessive efficiency loss. 1/ Do it aerodynamically or electrically? 2/ An adjustable device, if one exists, in opposition to the basick planetary gears might be applicable to yaw control. A change in collective or power may require an adjustment to the 'brake'. Not very good.
• How does one; find, design and build a jet-pinwheel?
• How does one start the jet-pinwheel?

• By Nick Lappos:
• Nothing new here, guys. The tip jet loses lots of power, and makes lots of noise. The inertia is up because the blades are very heavy, due to the hot gases they have to transmit.
• Tip jets typically need 30 or 40% more power than a conventional helo, this one is no exception - note the engine it needs for a 1700 lb machine.
• Hiller HJ-1 Hornet tip-jet helicopter ~ While the machine did have its drawbacks, including a noisy interior and short range,...
• Though the concepts pioneered by Hiller in the US and Sud-Ouest in Europe offered promise in simplifying helicopter design, they never proved to be very successful. In addition to autorotation problems, the tip-jet design required rotor blades to be made stronger and heavier than conventional blades in order to support the heavy engines mounted on the tips. Both the hot-cycle and cold-jet techniques also proved to be less efficient than more typical helicopter designs. As a result, tip-jets have not resulted in good enough performance to justify replacing the tail rotor, so the idea has never become a truly commercial success in production helicopters. Note that the autorotation and the need for stronger and heavier blades are not concerns for the idea on this page.
• Fuel Consumption may not be a serious concern since the craft is intended for recreational use.
• Noise is a concern. Is it possible to put a high-temperature multi blade(vane) fan in the path of the discharge that will

• It appears that the tip-jet configuration has a slow forward speed. Perhaps reducing the thrust from the retreating thrusters will overcome this potential concern.
• Limitation on the speed of the thruster. 2:1 Thrust : Tip-speed

• Patent ~ US 3,930,625 ~ Steam-powered aircraft (rotorcraft
• http://www.uh.edu/engines/epi1884.htm
• FLYING STEAM ENGINES
• Potential features:
• Reduce noise?
• Less fire hazard etc.
• Will take a few minutes to 'warm up' but this should not be an obstacle for recreational flight.
• The additional weight of the water will be a disadvantage. However the water, like the fuel, is an ever-decreasing weight as the flight progresses. In addition the efficiency may result is less fuel being requires. Also, in the event of an autorotation, the water (and the fuel) could be discharged before the landing.
• Consider having only advancing jets provide thrust during forward flight.
• Configuration:
• Consider a type of helicopter-gyrocopter where the steam is used solely to drive the rotor for takeoff and landing. The steam is then directed to the propeller lobe-motor and after it some goes to partially power the rotor while most is condensed and recycled.
• Words:
• "flash steam powered" Probably not the way to go.
• Read the last few posts in this thread. http://www.pprune.org/rotorheads/269799-sikorsky-xv-2-stop-rotor.html
• See Rotary Wing [High Performance Steam Engine]

• OTHER: Miscellaneous - Thoughtless Ideas - Root Jet Rotor The root jets deliver high volume - low velocity thrust.
• Ramjet-powered helicopter NHI H-3 Kolibrie
• Fairey Rotordyne
• Pulse-Jets
• Rotor-Craft RH-1 "Pinwheel"
• US 5313784 Solid fuel pinwheel power plant and method Maybe not.
• US 7337606 Rotary ramjet engine Maybe not.

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