jetpack
Nov 15, 2002, 05:12 PM
I'm planning a building project, and it's a 1957 Berkeley Models Douglas F4D-1 Skyray delta wing.
It's a rare kit, being the first ducted fan kit produced. It was designed for FF or CL, but with todays power and lightness of equipment, a micro system will fit and be light enough to do the job, and a Cox TD.
The TD is something I have to stick with, due to it being a pusher design. Its the only motor I can find besides their reed-valve that can turn LH with Cox's crankshaft option and lack of LH impeller options.
The plane itself is a stick and tissue covered model, with the all up FF weight of 11oz, and a wingspan of 25". It is also a delta wing craft, making it suitable for just simple two-channel elevon control.
The biggest question of the project at this point is this: What impeller should I start out with? The kit impeller that was supplied with the kit is a simple six-blade soft, stamped aluminum blade, simply not up to the task of modern power or performance, and since the kit itself is completely intact and in great condition, I would like to keep it as such, and simply copy it.
Does anyone have ideas for how to go about keeping this plane a gas powered 1/2A pusher design?
I remeber Kress and Midwest USED to have a 1/2A ducted fan unit, but those are no longer produced, or easy to find used at a reasonable price, and I also think those were tractor units to start with.
I'm kinda stuck here with a good design and simple build, even though it is very close to scale. It would be a very cool plane to play around with if I can get the propusion deal straightened out.
It's a rare kit, being the first ducted fan kit produced. It was designed for FF or CL, but with todays power and lightness of equipment, a micro system will fit and be light enough to do the job, and a Cox TD.
The TD is something I have to stick with, due to it being a pusher design. Its the only motor I can find besides their reed-valve that can turn LH with Cox's crankshaft option and lack of LH impeller options.
The plane itself is a stick and tissue covered model, with the all up FF weight of 11oz, and a wingspan of 25". It is also a delta wing craft, making it suitable for just simple two-channel elevon control.
The biggest question of the project at this point is this: What impeller should I start out with? The kit impeller that was supplied with the kit is a simple six-blade soft, stamped aluminum blade, simply not up to the task of modern power or performance, and since the kit itself is completely intact and in great condition, I would like to keep it as such, and simply copy it.
Does anyone have ideas for how to go about keeping this plane a gas powered 1/2A pusher design?
I remeber Kress and Midwest USED to have a 1/2A ducted fan unit, but those are no longer produced, or easy to find used at a reasonable price, and I also think those were tractor units to start with.
I'm kinda stuck here with a good design and simple build, even though it is very close to scale. It would be a very cool plane to play around with if I can get the propusion deal straightened out.