1764

Item 1764

OTHER: Helicopter - Outside - MicroLite - Backpack & Foot landing

A collection of microlite helicopters, such as backpack helicopters.

Notes:

A backpack helicopter is a helicopter strapped to the back of the pilot which could allow the pilot to walk around with the craft.

The pilot may sit on a bicycle seat or hang from the rotorhead in a harness.

The craft may have a 'flip-up' seat, which will provide more comfort during flight, while still allowing for an unencumbered foot landing.

The upper porting of the harness, if the harness has a very strong back, will loosely overwrap the pilots shoulders so that the rotorhead cannot make contact with the pilot's head.

The pilot's harness maybe a molded composite shell comprising; seat, back and, over-the-shoulder straps etc.

The battery pack(s) may attach to the sides or back of the pilot's harness.

The battery pack(s) may hang from cables attached to the pilot's harness; for landing, flight and/or take-off.

The battery pack(s) may be dropped shortly before landing and a remaining capacitor or very small battery pack provide the electrical power for a short duration during an autorotative landing.

Would the landing without the usual weight of the batteries present a problem for the pilot, who is already showing some anxiety over the act of an emergency landing?

Some or all of the three or four posts might be rigidly connected to the rotorhead and move with it

Alternatively, some or all of the three or four posts might be rigidly connected to the pilot's seatback and move with it.

Weight Ratio: (payload to craft)

Helicopter:	Maximum:	Payload:	:	Empty:	Ratio:	Disk Loading:	Notes:
Sikorsky S-76A	10,300 lb	4,754 lb	:	5,546 lb	0.86:1
Robinson R22	1,370 lb	540 lb	:	830 lb	0.65:1	Disc loading: 2.61 lb/ft²
Mosquito	500 lb	296 lb	:	254 lb	1.16:1	Disk loading 2.16 lb/ft²
Ultrasport - 254	525 lb	273 lb	:	252 lb	1.08:1
Schoeffmann	260 lb	183 lb ⁽¹⁾	:	77 lb	2.38:1	Disk loading: 4.72 lb/ft² ⁽³⁾

(1) Includes Franz's weight of 80 Kg plus 7 lbs of fuel.

(1) Franz said that the craft weighs 34 - 35 kilograms.

(3) Based upon 36 sq-ft at a GW of 77 lb [EW] + 176 lb [pilot] + 7 lb [misc.] = 258 lbs, which is a disk loading of 260 / 55 = 4.7 lb/sq-ft².
The rotor's radius MIGHT be as large as 51.3" = 8.55 ft. This will be a disk area of 57.4 sq-ft. and this will give a disk loading of 250 / 51.3 = 4.87 lb/sq-ft².

Thoughts:

What defines 'Backpack'?

An 'absolutely' rigid rotor (such as a propeller) will not have a teetering hinge. But it does have a gimbaled rotorhead.

Propellers:

IVOPROP

Ultralight Model Quick Adjustable Prop, Two-blade, 48"-72" diameter, 6 lbs. This may be the one used by Franz Schoeffmann.

Medium Propeller, Quick Ground Adjustable Medium Propeller, Two blade, 52"-74" diameter, 11.4 lbs, Too heavy.

Related Material:

OTHER: Helicopter - Inside - Single Rotor - All Electric Backpack (PAV) (UAV), See picture and Rotary Wing Forum thread in 'Miscellaneous Stuff:'

OTHER: Aircraft - Gyro/Heli - Non-powered ~ Just an idea by me.

AUTOGIRO AS HANG GLIDER ? ~ An outside non-powered autogyro.

http://www.rotaryforum.com/forum/attachment.php?attachmentid=61105&stc=1&thumb=1&d=1253439215

Sablier:

Sarasota Herald-Tribune ~ Sept. 29, 1954

"HELICOPTER DEMONSTRATED - French inventor George Sablier demonstrates his one-man helicopter at the International Meeting of Individual Helicopters in St. Etienne, France. Propelled by a six-horsepower engine, the device weighs 60 pounds and is said to fly about 31 miles per hour for ten hours. A special apparatus prevents the pilot from gyrating with the propeller."

More Information:

http://www.aqpl43.dsl.pipex.com/MUSEUM/TRANSPORT/personalheli/personalheli.htm

Baumgartl:

All of these had large rotors and limited power. This probably resulted in slow responses to cyclic and collective input.

Baumgartl Heliofly I
Baumgartl Heliofly III-57
Baumgartl Heliofly III-59 This is not a backpack, which brings up the question of what defines the backpack helicopter

GEN-H4:

http://www.worldrecordsacademy.org/technology/smallest_Helicopter-world_record_set_by_GEN_H-4_80288.htm

http://www.youtube.com/watch?v=Lf3YOLQUU6o&eurl=http://www.worldrecordsacademy.org/technology/smallest_Helicopter-world_record_set_by_GEN_H-4_80288.htm

http://www.youtube.com/watch?v=sDC8Cs5gmqc

http://www.youtube.com/watch?v=Hgn1Psq0V24 It states 100 k/h

http://www.youtube.com/watch?v=aTcNcA_zViw&NR=1

Franz Schoeffmann:

The front posts appear to be rigidly attached to the rotor assembly.

The rear post appears to have a flexible mounting to the principle assembly.

There is a cord between the feet of the from posts, possibly to stop them getting to far apart.

He sits on a seat and it appears that he may have strap that holds his butt in the seat, and perhaps his upper body back.

The feet of the three posts are about 10" of of the ground when he is standing erect.

It appears that the blade grips are flat plates and their length puts the blade attachment bolts at about a 10" radius.

http://www.flycastelluccio.at/cms/up....04.05_512.wmv

http://www.youtube.com/watch?v=aWG-rq8X1Mg&feature=player_embedded#t=26

http://www.youtube.com/watch?v=BmuXTzU8-jM&feature=player_embedded

http://www.youtube.com/watch?v=1S0w1yYSwiI&feature=related

http://www.youtube.com/watch?v=WHA8PlieHIg&NR=1

http://www.flixxy.com/personal-helicopter.htm

http://www.youtube.com/watch?v=f09_yvcASLM

http://www.youtube.com/watch?v=2W3gamijezc

http://www.youtube.com/watch?v=7RZOiEryX0c&feature=related

Additional Information:

Thread on Rotary Wing Forum about Franz Schoeffmann's coaxial helicopter.

http://uk.groups.yahoo.com/group/Back-Pack-Helicopter/message/1893

"His coaxial rotor backpack helo is powered by a 27 hp liquid-cooled go-cart engine. The rotors are two sets of composite Ivoprops (one set reversed pitch). These are OEM items Bob. The prop/rotor hubs are custom-made."

_________________________

Posting on a Forum:

>I can start by giveing you some general info and let the others correct
>me where I am wrong <Grin> as my memory is sketchy at times!
____________________________

> The "tripod" landing gear is made out of two short steel pipe sections
> welded together to form a "V",into which aluminum tubes are slid to
> give the desired lenght.Between the leggs of the steel tube "V" is a
> steel eye welded at the apex of the "V".The third steel legg of the
> tripod has a steel hook welded onto which can be clipped in the steel
> eye and has the ability to move freely in all directions.This third
> steel tube also receives an aluminum tube matched to the lenght of
> the "V" leggs.This third legg has a bycicle saddle mounted for the
> pilot so when the craft is in the air,the pilot can move the "V" leggs
> in front of him to stear the craft.
> A simple pin connection makes the aluminum tubes removable in a matter
> of seconds so to speak.
>
> The steel "V" structure is the base for the "lifting component" which carry the engine-steady shaft-transmission etc.
> The single cylinder engine has a centrifugal clutch (go-kart) with a small sprocket and a chain drives a (custom made) large sprocket to match the engine RPM to the needed rotor RPM (around 1000 rotor rpm). On top of the large sprocket is an aluminum spacer block-the lower rotor hub strap-bearing block-upper rotor hub strap-steel plate with one conical gear. A high grade steel bolt, holds the two "satelite" gears, which goes straight through the steady shaft. On top of the two satelite gears is a "reversed" copy of the lower rotor assembly:steel plate with conical gear-lower rotor hub strap- bearing block-top rotor hub strap,and of course no large sprocket up there (grin-grin).
>
> This is the basic concept of the Schoeffmann helicopter.
>
> The "yaw" rudder or vane is a simple 3 mm plywood flat sheet formed more or less into an "aircraft shape" (whatever that may be) which slid and fastened into a cut-out slip in the rotating tube. This tube is slid over a thinwall steel tube which is welded as an aft facing extension of the steel "V".
> A very simple but effective two-cable system secures the rudder tube into the "bearing" tube and via a small lever,actuated by your index finger and thumb,the vane provides adequate torque force to move the > helo around it's vertical axis.
>
> Well guys,if after this explanation the confusion is not complete I will give it another try next time hahahahah !!!!
>
> Gilbert

_____________________

From Yahoo:

Mr.Schöffman's heli-pack weighs roughly 35 kg! [77 lbs total] I've seen this machine and I can assure you that there is not one single part which is not needed.

_____________________

He has a tuned exhaust on his craft. This implies that he is probably running the engine at close to it's maximum power. It should be noted that the tuned exhaust reduced the range of RPM for maximum power output.

_____________________

For more information related to Schoeffmann's craft see; DESIGN: Electrotor-MicroLite - Rotor - Disk - General

Information from H.G. conversation with Franz Schoeffmann on January 18, 2011:

The engine is a Rotax that has been modified for go-cart racing. It delivers 28 hp and weighs 22 kilograms. It is reliable for 15 to 30 minuites.
It is too expensive for him to keep buying the engine. And, without authoritative capability the flying is risky.
The craft weighs 34 - 35 kilograms.
It is extremely vibration-free, however he has not flown it at meaningful forward speeds.
The vertical fin works well for yaw control. The thumb on his non-throttle hand positions the fin.
The weight-shifting requires the same force as that of piloting a hang-glider and at 75 years of age he had no problem piloting the craft.
He believes that electric is the future way to go.
He mentioned an electric motor that delivers greater than 20 HP and weighs 2 or 3 kilograms but Hans forgot the name of it.
He was told that my project was intermeshing. He agreed with the configuration and spoke very highly of Flettner.
He now flies a gyro.

Information from H.G. conversation with Franz Schoeffmann on February 20, 2011:

There is no suitable engine for his application. The one he used is like a racehorse. Use it and then throw it out.
Franz weights 80 Kg.
The original rotor diameter was 2 meters [6.56 ft]. He then increased it to 2.1 meters [6.89 ft]. He did not notice any improvement by going to the larger diameter.
He mentioned the 18hp, 4.7 kilo motor that is used for backpack parasails. He said the battery was 10-15 lbs.
Franz is 75 years old and has no intention of building another rotorcraft.
He said that his craft was extremely dangerous because of its inability to autorotate. But, he could not find an appropriate larger engine or larger blades.
His engine had a very high RPM and he could not go to a larger ratio reduction.
When ask what his biggest limitation was he said it was the engine.
After a while the fun wears off so he went back to gyrocopters
There is no engine for a 90 K pilot. He mentioned a Belgium engine that is; 4-cylinder boxer, weighs 47K, 80 HP, 2,00 RPM, liquid cooled. But he said that it is too big for an extremely light helicopter.
He said that he has been interested in gyrocopters since 1952.
He mentioned a gyrocopter and the name [Corielus?]. He said that it has absolutely no vibration. It uses motorcycle steering dampeners for fore&aft dampening.
Hans mentioned his long time search for the 'perfect helicopter' and Franz mentioned his preference for electric if it were not for the weight of the batteries. Franz likes the quietness of electric flight.

_______________________

Disk Loading:

72" Ivo diameter + 2x10" radius hub plate = 92" dia. = 46' radius = 3.85' radius = 46.6 sq-ft area for one rotor.
Assume that the effective disk area for rotors at a 6' gap is 55 sq-ft.
At a GW of 77 lb [EW] + 176 lb [pilot] + 7 lb [misc.] = 260 lbs, which is a disk loading of 260 / 55 = 4.72 lb/sq-ft.

Information from H.G. conversation with Franz Schoeffmann on October, 17, 2011:

Schoeffmann's IVO blades are the 72" long ones and are the Ultralight. I forgot to ask which pitch range he bought.
From the above picture, which has the curtain with vertical line, it appears that the hub-bar adds 500mm to the diameter.

From Yahoo:

It has counter rotating props that were specially made for him to his specs.
The single cylinder engine has a centrifugal clutch (go-kart) with a small sprocket and a chain drives a (custom made) large sprocket to match the engine RPM to the needed rotor RPM (around 1000 rotor rpm)

Safety Harness:

Consists of two straps from the rear mast at waist level, or perhaps higher. One strap is brought from his right side and attached to the nose of the bicycle seat at his crotch. The other strap comes from the left side.

From Cita on Rotary Wing Forum November 5, 2009:

I think the rotorcraft in the picture belongs to Hugh, one of the guys on the back-pack helicopter forum who's building a Schoeffmann.

They are indeed IVO blades, you can contact Hugh for exact numbers.

October 17, 2011

Franz mentioned in a conversation with Hans today that he has just about completed an electric backpack helicopter. He has been hopping with it on one motor, while waiting for delivery of the second motor.
He said that it should be on You Tube in a few days.

November 6, 2011

Franz is still waiting for the motor manufacture to finish building the second motor.
It weighs 4.75 Kilo [19 lbs] and delivers 18 HP.
He was not asked what the make was.

Links to the electric motors that Franz is using:

Electrotor-SloMo ~ Motor ~ Geiger

Greek Backpack:

SWING-AVI

COAXIAL HELICOPTER KITS

FACTORY: INDUSTRIAL ZONE PATRAS GREECE

PO BOX : 1223 PATRAS - GREECE 26001

TEL/FAX: +30 2610 432597

E-MAIL:swingavi@gmail.com

Making dreams come true

Dear Sir,

Swing - avi constructs since 2003 the personal coaxial helicopter Kits SA4H. The kit is simple to use and easily assemled in (8) eight hours. Its operation is very easy throughout the flying.

The helicopter can be easily transported and weighs 35kg. The cost of the kit is so low so you can now fly for fun whilst flying for less.

For more information you can obtain the SWING SA4H information pack at the cost of 30 Euros or 40 US Dollars payable by cheque and posted at Postal Address: . EVLIATIS APOSTOLOS . PO BOX :1223 PATRAS - GREECE 26001

The SA4H information pack includes:

1x DVD with the full flight video- photos- specification- kit price list for dealers

-With Regards

Evliatis Apostolos

Swingavi Manager

swingavi@gmail.com

From the pictures its appears that the two forward posts are firmly attached to the rotorhead assembly. On one picture it shows these posts only coming down far enough for hand grips while on another picture it show froward posts that will come all the way down to the ground.

Ti appears that the round tube model of rear post is mounted to the rotorhead assembly by a rubber type of joint that will allow longitudinal rotation and possibly some lateral rotation. Both of the two models of rear posts go to the ground.

In the round tube supporting the pilot is strapped to the back post by a shoulder strap., that may also attach to the seat.

It looks like he went from the square tubing to the round tubing, and the rount tubing araingment looks possibly to that of Franz Schoeffmann's.

Cita ~ Rotary Wing Forum:

Backpack helicopter testing. http://www.youtube.com/watch?gl=NL&hl=nl&v=YXBxCyaYj_I

From HobbyCAD ~ Rotary Wing Forum:

http://www.rotaryforum.com/forum/showpost.php?p=270002&postcount=1

Pentecost E-III Hoppicopter:

http://www.shanaberger.com/hoppicoper.htm

http://www.pimaair.org/collection-detail.php?cid=220&pn=1

Main Rotor Diameter 12 ft Weight 88 lbs Engines Two-cylinder piston engine with 20 horsepower Crew 1

SportHelo:

http://www.sporthelo.com/

From Jens ~ Rotary Wing Forum:

French Backpack Pictures:

Backpack_French_1.jpg

Backpack_French_2.jpg

Fanman 550E

Raphael Celier:

A portable helicopter designed confidentially for the French Army. It catches the imagination, still was a dangerous prototype to operate. Serial version where to get shrouded propellers turbines like. The machine is in exact shape as per my last flight with it, even the mannequin is wearing my flight suit.

Chancellor Aviation FANMAN 550E

Freewing - Prototype:

Weight 115 lbs

16 hp total from 2 engines

Uses Ivo props. Unlike Franz Schoeffmann's these blades do not have root end extensions (hub-bar) to give a larger disk area.

Reduction is 4:1 planetary gearheads to 3:1 spiral bevel.

Does not have sufficient thrust to lift off.

Unknown - from Jetman:

Notes.

Related Threads on Forums:

Rotary Wing Forum ~ Another attempt, back-pack helicopter

Related Information on This Web Site:

Last Revised: December 18, 2011