Autogyro with a Difference

**Bluewavestudios** · 01-08-2004

Thought I would post this one up for you, dug out of my parents shed after many years in Hibernation. (Have lived away from the area for quite some time but am now back) Getting all the old models out, refurbishing them and putting them back into service.

No prizes for guessing which Helicopter this is based on, It has had a few short hops and has actually been airbourne. As can be seen it was never finished fully with markings and weapons pods etc on the stub wings until testing was completed. Built from my own plans and powered by an Irvine .21 engine up front. 3 channel R/C. To give and idea of size, that is a 1/10th scale R/C car in the background. (under construction also)

Regards.........Mark

duncan · 01-08-2004

A realy interesting project. is that heli or Hobbit head? My tuppenceworth would be slim fuz right down(as per real one) massive reduction of engine pods. Enlarge tail fin and tailplane. Go for modern flexi delta head and 3 blades,broader chord with Clark Y section. 25 size engine. Minus 1o on blades , reduce incidence on stub wing to zero or +1o or +2o max. It would be a nice change from vintage style autogyros. I`ll be first in the queue for plans when you have got it organised. Should be a sell-able design. Delta head details from www.autogyro.com Good luck with it.

**wonwinglo** · 01-08-2004

Stunning project Bluewave,reminds me of the Jim Morley Fairey Rotodyne project,tell us a bit more about the mechanics in this ship ? would love to test fly this one ! I just love a challenge.

**Bluewavestudios** · 02-08-2004

Thanks for your comments guys. As stated this machine is only based on the Apache and was never intended as an exact copy, but I think have still captured the feel of the original machine though.

I have considered a bigger engine and maybe even a 4 stroke...so will see in due course.

Fuselage construction is just basic balsa box girder construction with ply bulkheads where necessary. Thin plywood skin all over which has resulted in a strong but very light structure. The dummy engines are nothing but balsa boxes, Tailplane, Fin and stub wings are all balsa built up constructions.

Rotor Blades are of a Clark Y type section, home made using Ramin for main centre spar, standard hard balsa leading and trailing edges and all balanced of course.

Rotor Head is also home made using two proper R/C helicopter head plates (Kalt items) which allow for flapping hinges. (yes I have 2 Heli's too...!!) (you will see in the pics above that the blades do droop under their own weight)

Blade holders are also home made items although I have redesigned the rotor head and I am now building a new one. Swash plates & linkages are dummies but work well as they rotate very freely and add to the rigidness of the rotorhead)

Undercarriage is a fully working Oleo sprung type and works very well. (home made with brass tube, piano wire, brass collets and 4 springs)...waits for well known german pun now

Rotor Diameter = 42.5 ins
Blade chord = 1.75 ins
Overall length of machine = 40.5 ins
Overall height to top of mast = 12.75 ins
Fuselage width (not including dummy engines or sponsons, if that is the right word...!!) = 4 ins at widest point

Tailplane span = 12 ins
Chord at centre = 4 ins
chord at tip = 2.25 ins

Tailfin across top = 3 ins
Tailfin at base to tip of rudder = 5 ins

Overall weight of machine 3.25 lbs

Don't ask me for metric measurements coz you know where you can shove them.

If you want to know anymore please feel free to ask.

and finally here's a top down shot for you.

Regards.............Mark

**Bluewavestudios** · 02-08-2004

ps.......

Forgot to say...blades are currently set at -5 mins degrees inc but they spin up ok, they can be reduced easily.

Tailplane is the elevator on this machine and is basically an all flying tailplane. (Full floating type)

The Rudder on the tailfin actually has a full 1" deflection either way which is ample for this machine (Probably more than most planes) Look again at the middle pic above and you will see that the actual rudder line is half way down the tailfin and not at the end of the black rudder markings, that is probably the cause of confusion)

Although you probably can't see them on the pics, all the led lights on the stub wings, behind the rotor mast, belly radar and on the tail fin are working items too...powered by square 9 volt pp3 battery

Regards.......Mark.

**wonwinglo** · 02-08-2004

She should fly fine,get the centre of gravity right and do initial trials in windy conditions,these autogyros lift off as soon as there is any angle of attack on the blades,a few test hops should tell you if she has the urge,you might need to experiment with the thrustline a bit,usually lots of downthrust is required,best of luck !

duncan · 02-08-2004

Agree that will fly. Bit too much negative on rotors I think. -5 will certainly get them spinning quickly but at some loss of lift , try to get them spinning with as little neg. angle as possible. Dont forget the flat bottom on the Clarkey isnt zero degrees. Think I`d couple the rotor tilt and rudder(left tilt=left rudder). Are you going to get some drawings ? Like Wonwing I`d have a go at one. While we are on the subject of autogyros , any interest in an autogyro only fly-in? Chance to see other nutters efforts etc etc.

**Bluewavestudios** · 04-08-2004

Well since your last postings, Blade incidence has been dropped to - 2 degrees, I forgot to say that the engine does have 2 degrees downthrust by use of washers under the engine on the mount, the beauty of this design is the semi open cowl that allows for easy engine swaps and adjustments as well as allowing plenty of cooling.

Did anyone spot the Alien in the back seat on the first pic by the way...???. Save pic and then zoom in and you will spot him looking straight at you. On first glance you will see the normal pilot but zoom in and he changes lol...!!! I noticed this the other night when I took the pics....quite spooky !!!!

Regards.....Mark

duncan · 04-08-2004

Been doing a pick-up from Area 56 ? I always believed "Greys" existed ! More downthrust needed perhaps 5 to 8 degrees even. They have terrible drag from rotor. Get it flying and give us all a thrill

**wonwinglo** · 04-08-2004

Bluewave you will get a surprising amount of lift from those stub wings,they will also assist dampening of the main rotors.
I always fancied building that Boeing Vertol or even the Osprey ! that would present some problems with those massive props,I think that I would progressively alter the angle of attack on such a machine and tread carefully on the first test runs just constantly checking the trim,the full size is a bit of an handful I understand.
These projects are not for the timid but boy are they fun !!