Need for speed, best prop for OS 46

[AirbusPilot]

Hi,

I am building a jet, so I want to have a jet trainer so I am going to use a Great Planes Patriot with and OS 46, I want to know what Prop will be the best for speed???, do not need static thrust just final speed because I want it to be like ducted fun or jet.

Thanks for your help ;)

[fhhuber506771]

That actually depends on how heavy the model turns out and how clean the areodynamics are. Start with a 10X7. The aircraft design will limit your top speed possible.

Patriots LOOK fast and can fly at a pretty good speed, but they are far from the fastest thing out there for a .40/.46

[GregG]

At the club I belong to, the Diablo Valley Radio Controllers (http://www.dvrc.org) we race stock class T-34's made by World Models. The engine being used is an unmodified OS .46. Most of the racers have gone to a 9.5 X 7 Bolly prop to get the RPM up to max HP level in flight. However the T-34 is a fairley draggy airframe and needs that large of a diameter prop to get enough thrust to pull it through the air.

If the Patriot is a smoother airframe you might get by with a slightly smaller diameter and higher pitch. Perhaps a 9 X 8 would work for you. APC makes props all the way to 10" pitch in 7", 8", and 9" diameters so you do have a bit of a choice.

[Italian Flyer]

put a OS .90 Ducted fan engine with a 10x10 prop if you want speed.
buy a 12x10 and cut it down to 10x10 and rebalance. Speed will exceed 200mph if the airframe can take it. With some mods to the airframe it might.

[Z06kal]

Hah I've seen the GP patriot. Its a balsa built up plane with huge control surfaces. And a very floppy construction. Once you add rear weight to counter balance the 24oz engine up front along with its 16oz fuel tank (which is probably as big as will fit and probably last all of 2-3 Minutes) your looking at a pretty heavy plane. With that much HP and speed I'm sure the wing and control surfaces will quickly flutter not to mention the first time you pull back with any force at all the heavy AUW and floppy construction will probably break the wings real fast. If you get the XL version made for a .90 your looking at more drag so I'm not sure how close it will come to prop pitch but I would question that wing/airframe too at speeds much above 130.

[blizzardwarrior7]

Id say go for a 9x8 or even a 10x8 for max speed. However, like people mentioned, I dont think this plane is realy meant for all out speed.

[buzzingb]

Your right the Patriot is draggy and slow but the plane is built like a tank. It won't fly apart unless there is flutter and that will be opperator error if that happens. I have been flying this plane for about a year with OS 50 and 9X9. The 46 will need a little less like a 9X8 maybe. This puppy needs the fuse and the wing thinned down a little to get the speed up. The fuse looks as large a 60 size plane.

[daven]

If it is an O.S. .46AX stick with the 10x7, if it is the O.S. .46FX try the APC 9 1/2x7 1/2 NN.

[MrPropJet]

if you go the route that italian flyer suggests be very carful of prop selection as a ducted fan engine would unload to somewhere about 20,000 in the air while it might be ok, the rating for an apc 10" is about 19,000 when using ducted fan engines it is strongly recommended that you use a carbon fibre prop... better still CF 10 x 10 cut down to 9 x 10 you should get about 22,000 rpm..thats plenty of speed pending air frame but a patriot would need beefing up to sustain that.

all in all not the best reccomendation as the others have mentioned it's not an all out speed frame, run your .46 and probably the 9X8 would be a good speed prop

[AirbusPilot]

I am flying my patriot with OS46FX with APC 9x9 getting 13,200 rpm. I have to say that the plane is the fastest in the field even faster than a Skymaster F-15. The airframe is very strong and will get a lot of G`s and speed with easy. We made some modes, we do not use the air intake because is just add drag and we add big flaps for landing. I will install a GPS soon to meassure the speed also I will try an APC 9x8.

[Turbo442]

I shortened the header on my OS .46 AX with a Mac 8.5 pipe today. Saw 18,000 rpm static with an APC 8X9 sport prop on 30% heli fuel. vertical is awesome, hand launch no problem, good top speed. Airframe is a Weston Magnum.