Telemetry from a 60 size mustang
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Telemetry from a 60 size mustang
Hi everybody,
I too have purchased a telemetry unit. It yields altitude, rpm and real time airspeed via a pitot tube. I purchased a 60 size mustang (from ebay-believe it or not) and eliminated all but 1/2 inch of the belly scoop. This plane is purple, yellow and black, wingspan about 65 inches and fully sheeted. Flying weight is 8.25 lbs. For $150.00, it is a good deal. I powered the bird with an OS vrdf 91 using ab 11x10 apc prop. The engine also utilizes a full wave muffled pipe with manifold pressure to the tank and 15% omega fuel.
I tested the speed indicator by mounting the wing on top of my van about 18 inches above the roof and brought her up to 60 mph. The reading of the telem unit was 60 mph and the van's speedometer read 60.4mph. This was reproducible. I also tried it at 70 mph later on and the result was the same.
Coming down at a shallow dive from 400 feet, the plane did 164 mph top end. I later downloaded the data and found that the engine was turning 21,200 rpm. The data recorder transmits real time and then also stores data for later download.
My friend Jerry is going to help me put retracts on it, clean up the cowling and pipe area and other drag inducing areas. Possibly the use of an 11x9 or a cut down 11x10 or 11x11 might yield even more speed. We hope to push her nearer to 200.
I would welcome any ideas on how to accomplish this goal.
I too have purchased a telemetry unit. It yields altitude, rpm and real time airspeed via a pitot tube. I purchased a 60 size mustang (from ebay-believe it or not) and eliminated all but 1/2 inch of the belly scoop. This plane is purple, yellow and black, wingspan about 65 inches and fully sheeted. Flying weight is 8.25 lbs. For $150.00, it is a good deal. I powered the bird with an OS vrdf 91 using ab 11x10 apc prop. The engine also utilizes a full wave muffled pipe with manifold pressure to the tank and 15% omega fuel.
I tested the speed indicator by mounting the wing on top of my van about 18 inches above the roof and brought her up to 60 mph. The reading of the telem unit was 60 mph and the van's speedometer read 60.4mph. This was reproducible. I also tried it at 70 mph later on and the result was the same.
Coming down at a shallow dive from 400 feet, the plane did 164 mph top end. I later downloaded the data and found that the engine was turning 21,200 rpm. The data recorder transmits real time and then also stores data for later download.
My friend Jerry is going to help me put retracts on it, clean up the cowling and pipe area and other drag inducing areas. Possibly the use of an 11x9 or a cut down 11x10 or 11x11 might yield even more speed. We hope to push her nearer to 200.
I would welcome any ideas on how to accomplish this goal.
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RE: Telemetry from a 60 size mustang
rc-guy
I have collect two 90 vrdf units intending to create something of the same thing. The German speed guys have these things down pat. Recommended prop to me was a 10 X 10 carbon fibre prop or if not available, a apc cut down to that size. Watch the prop, the rpm's you are turning are past the recommendation limits. ENJOY Keep us posted.
I have collect two 90 vrdf units intending to create something of the same thing. The German speed guys have these things down pat. Recommended prop to me was a 10 X 10 carbon fibre prop or if not available, a apc cut down to that size. Watch the prop, the rpm's you are turning are past the recommendation limits. ENJOY Keep us posted.
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RE: Telemetry from a 60 size mustang
Rc-guy:
Sorry, forgot to tell you, don't use more than 5% nitro in that thing or the life span will be squat. The 10 X 10 should be good for 22-22500 Engine will turn 24 but is asking for trouble. See ya
Sorry, forgot to tell you, don't use more than 5% nitro in that thing or the life span will be squat. The 10 X 10 should be good for 22-22500 Engine will turn 24 but is asking for trouble. See ya
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RE: Telemetry from a 60 size mustang
Update on telemetry ...
By cleaning up the airframe a bit and changing spinners, we are now up to 173 mph. Still using 11x10 apc with 15% omega.
RPM was 21,450 ish
Does anyone think a 10x11 might work better?
By cleaning up the airframe a bit and changing spinners, we are now up to 173 mph. Still using 11x10 apc with 15% omega.
RPM was 21,450 ish
Does anyone think a 10x11 might work better?
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RE: Telemetry from a 60 size mustang
ORIGINAL: r-c-guy
Hi again....The picture I uploaded was a stock picture. I could upload actual photos if anyone is interested.....
Hi again....The picture I uploaded was a stock picture. I could upload actual photos if anyone is interested.....
I'd like to see it since I have the same plane. Flew it alllast year and rebuilt it better. Have a G2300 on it and put a solid front end. Moves along about 120mph. at most.
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RE: Telemetry from a 60 size mustang
Your prop tip speed well exceeds critical mach and is close to the speed of sound. I suspect a lot of prop noise. If your airframe is clean enough maybe a 10" prop with a very high pitch would work better. You would still exceed critical mach though. It would take a 10x14 to equal the load factor of the 11x10.
While O.S. rates the engine at 4.8 hp at 22,000 rpm, Thrusthp shows over 10 hp to turn a 11" prop at 21,450. Not disputing your #'s but wonder whats going on.
The O.S. site says this about fuel for your engine --
Fuel with 20% MINIMUM lubricant content and 20%-50% Nitromethane
Wildcat Ducted Fan fuel exceed these requirements
Interesting thread, keep us informed.
While O.S. rates the engine at 4.8 hp at 22,000 rpm, Thrusthp shows over 10 hp to turn a 11" prop at 21,450. Not disputing your #'s but wonder whats going on.
The O.S. site says this about fuel for your engine --
Fuel with 20% MINIMUM lubricant content and 20%-50% Nitromethane
Wildcat Ducted Fan fuel exceed these requirements
Interesting thread, keep us informed.
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RE: Telemetry from a 60 size mustang
I have this exact plane I bought on Ebay a year ago as a junker. I installed a G2300 and a Jettstream muffler. It also weighs in a hair over 8lbs. I stripped it over the winter and rebuilt it and installed new retracts and a solid front end instead of a cowl. This turned into one of my better flying planes at a speed of around 110mph. This being a 5000ft. Now at sea level i would expect maybe 125 for this thing.
I hate to poop on your parade here but your boasting speeds of 165mph going for 200 on a 90VRDF with this airframe and this weight. Now I have seen a 165mph Diamond Dust or a Magnum. I'm sorry here but I just don't buy any of this. I know the power a 90VRDF but this whole thing just does not wash with me. I know you tested ithe pitot tube on your truck and compared with the speedometer. I simply don't beleive it these speeds on this plane
I hate to poop on your parade here but your boasting speeds of 165mph going for 200 on a 90VRDF with this airframe and this weight. Now I have seen a 165mph Diamond Dust or a Magnum. I'm sorry here but I just don't buy any of this. I know the power a 90VRDF but this whole thing just does not wash with me. I know you tested ithe pitot tube on your truck and compared with the speedometer. I simply don't beleive it these speeds on this plane
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RE: Telemetry from a 60 size mustang
I can only tell you what the Eagletree readout states. We checked it against my van at 60 mph and it was within one mph of the states speed of the speedometer of the van. I cannot calibrate it at 150 or any other value over 70 or 80 mph since it is illegal to go that fast.
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RE: Telemetry from a 60 size mustang
The thing is a G2300, not a VRDF Mine is a 110mph plane. At sea level, maybe 125mph. Plus I am at 5000ft, With the engine you have up front, There is no doubt you could take this plane easy but 165mph? Not to start a qualm here but thats seems a bit much for this type plane at that weight. Was this out of a 1000ft dive? Maybe then, but I would like a more realistic number from level flight.
To get off track here, about a year and a half ago, we had a "radar gun"day. I knew their were going to be alot of disappointed pilots out there. Everyone was alway looking at other planes guessing speeds much higher than they actually were for years.. Propjets were going 130mph, Giant scale gassers at 120 plus and the whole thing. It was like catching a bigggggg fish. The speeds increase each time the subject came up.
So on this day, one guys big gas warbird average 98mph out of a high speed dive. He was very disappointed. My red Ultra Sport with a Jett 90 made it to 115 mph but its a 8lb plane and my DC F20 with a Jett 50 made it to 120mph. Now take in consideration our altitude here, these speeds are about as good as we are going to get. Jett gets 14500 on a 90 and 12something apc in Texas but i run the same thing and 12,500 rpm is tops up here.
To get off track here, about a year and a half ago, we had a "radar gun"day. I knew their were going to be alot of disappointed pilots out there. Everyone was alway looking at other planes guessing speeds much higher than they actually were for years.. Propjets were going 130mph, Giant scale gassers at 120 plus and the whole thing. It was like catching a bigggggg fish. The speeds increase each time the subject came up.
So on this day, one guys big gas warbird average 98mph out of a high speed dive. He was very disappointed. My red Ultra Sport with a Jett 90 made it to 115 mph but its a 8lb plane and my DC F20 with a Jett 50 made it to 120mph. Now take in consideration our altitude here, these speeds are about as good as we are going to get. Jett gets 14500 on a 90 and 12something apc in Texas but i run the same thing and 12,500 rpm is tops up here.
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RE: Telemetry from a 60 size mustang
I can only tell you what the readouts were. And yes, they were out of a shallow 400-500-- foot dive. Maybe we can get a video.....