She's finished and test flown. This one carries more fidelity to scale and is powered by a Super Tiger 75-2 stroke. Total weight, with the shroud will be under 17 lbs and was flown without the shroud initially. Wing loading falls around 20 ounces. Test flight was nearly perfect, only needing a slight amount of down elevator and about 2 clicks of right aileron. Engine quit during the flight, resulting in a bent nose gear as she ended up in rough terrain and tall weeds. No flight pictures yet but check back later. Now that I have built 3 models of the Stratos I have a high confidence level on the design criteria. It is an absolutely brilliant and efficient design with an unbelievable 20:1 glide ratio and very gentle flying characteristics. I now know exactly what I did wrong with my second model that was a little touchy in flight. I calculated the balance point incorrectly and it was on the verge of being tail heavy. On the right is what I saw in my mind as I built each model. This is the real one with the late Charles Ligeti at the controls. It was featured once on the Discovery Channel and is in their video .... Planes,Trains and Automobiles .... believe that picture came out of the EAA magazine. As I recall the real one was powered by a 40 hp. Konig sailplane engine .... cruised at about 110mph ..... nose gear was shrouded and when properly deployed the craft would fly sideways without banking. Or if you preferred you could deploy up flap and up elevator (on the canard wing) and it would come down like on an elevator. Was about 8 foot long with a span a little over 17 feet and a smidge over 3 foot tall. ...... George Sauer and I spent many a day trying to think this whole project out. Basically it is a box construction so is solid, but if you are off by 1/16 of an inch on anything then nothing fits together. Making a canopy like that was too big for my oven so got the people at Lanier to make 3 or 4 after I sent them my plug. Our Alien pilot has a sign around his neck that says ....... "take me to Monica". Wing Span 80 inches .... Fuselage length 39 1/4 inches ..... balance point 16% forward of Neutral Point for the test flight. Distance between average quarter chord points is 14 3/8 inches (26 5/8 inches at the root). (see the Design Link for finding the Neutral Point) In the near future I will add exact dimensions of my model. If you want my estimates of dimensions on the real airplane then click here Get the May 1990 Model Aviation magazine article as it tells most of the story. In addition if you check out my design info from my home web page there is a little section on canards and pushers and plan to add more as I get smarter. It tells simple ways to find balance points and all. Design The main point with the Stratos is that it has to be built very accurately. Initially I wouldn't add the shroud until the proper thrust line is determined by flying the model a few times. On my current model the thrust line appears to cross right at the top of the canard. If the shroud is attached before hand and you have to tilt the engine a little differently, then the entire shroud has to be re-mounted and will not mount to the wing the same way, so the slot in the wing will have to be modified. Another delicate problem is cutting the sweep angle of the canard. If it is 1/64 th of an inch off at the center it translates into a huge problem out at the tip where the vertical fins mount. One last item if you do build the model, you really do not need the movable rudder on the vertical fins. If you do want to do the rudders, then you should understand that the rudders should only move outboard and never inboard. For example if you input a left rudder turn, then the left rudder should move outwards and the right rudder needs to move only to neutral otherwise the right rudder ends up canceling out the left rudder as it would be adding the same amount of drag to the right side of the craft. Clear as mud, huh? The one I have just test flown does not have rudder control, just ailerons and elevator on the canard. Of course the elevators being up front move exactly opposite as on a tractor model. An upward deflection gives down elevator and an downward deflection gives up elevator. The canard needs to be mounted at no more than 1 1/2 degrees positive to the main aft wing. In addition I mounted the fuel tank right on the balance point and am drawing fuel to a 4 stroke 90 about 15 inches away from the engine and about 3 inches under the center line of the tank on the original model and the same distance on the current 2 stroke model. I have never had a fuel draw problem with the 4 stroke however the 2 stroke prefers a 2 bladed prop instead of a 4 blade prop. Initially I had a pumper on the engine and a header tank right behind the firewall but found they were unnecessary. Just use exhaust pressure to the tank. The front of the tank faces forward with the clunk aft. ........ That is about all I can think of and are the main points.......... Design Info on Canards My First Stratos Spec's on the Real Stratos Home Index Page Marv Reese copy write 11/1999-update 5/29/06
Making a canopy like that was too big for my oven so got the people at Lanier to make 3 or 4 after I sent them my plug. Our Alien pilot has a sign around his neck that says ....... "take me to Monica".
Wing Span 80 inches .... Fuselage length 39 1/4 inches ..... balance point 16% forward of Neutral Point for the test flight. Distance between average quarter chord points is 14 3/8 inches (26 5/8 inches at the root). (see the Design Link for finding the Neutral Point) In the near future I will add exact dimensions of my model. If you want my estimates of dimensions on the real airplane then click here Get the May 1990 Model Aviation magazine article as it tells most of the story. In addition if you check out my design info from my home web page there is a little section on canards and pushers and plan to add more as I get smarter. It tells simple ways to find balance points and all. Design The main point with the Stratos is that it has to be built very accurately. Initially I wouldn't add the shroud until the proper thrust line is determined by flying the model a few times. On my current model the thrust line appears to cross right at the top of the canard. If the shroud is attached before hand and you have to tilt the engine a little differently, then the entire shroud has to be re-mounted and will not mount to the wing the same way, so the slot in the wing will have to be modified. Another delicate problem is cutting the sweep angle of the canard. If it is 1/64 th of an inch off at the center it translates into a huge problem out at the tip where the vertical fins mount. One last item if you do build the model, you really do not need the movable rudder on the vertical fins. If you do want to do the rudders, then you should understand that the rudders should only move outboard and never inboard. For example if you input a left rudder turn, then the left rudder should move outwards and the right rudder needs to move only to neutral otherwise the right rudder ends up canceling out the left rudder as it would be adding the same amount of drag to the right side of the craft. Clear as mud, huh? The one I have just test flown does not have rudder control, just ailerons and elevator on the canard.
Of course the elevators being up front move exactly opposite as on a tractor model. An upward deflection gives down elevator and an downward deflection gives up elevator. The canard needs to be mounted at no more than 1 1/2 degrees positive to the main aft wing. In addition I mounted the fuel tank right on the balance point and am drawing fuel to a 4 stroke 90 about 15 inches away from the engine and about 3 inches under the center line of the tank on the original model and the same distance on the current 2 stroke model. I have never had a fuel draw problem with the 4 stroke however the 2 stroke prefers a 2 bladed prop instead of a 4 blade prop. Initially I had a pumper on the engine and a header tank right behind the firewall but found they were unnecessary. Just use exhaust pressure to the tank. The front of the tank faces forward with the clunk aft. ........ That is about all I can think of and are the main points..........
Design Info on Canards My First Stratos Spec's on the Real Stratos Home Index Page
Marv Reese copy write 11/1999-update 5/29/06