L Edge
Master member
This is going to be an interesting project. I decided to find out if I build with 64's and it doesn't work, insert 70's sometime in the future. Some of the other problems are the long fuse it has, address the negative thrust line, long ducting, and I am going to move the EDF's so in the future you can add the nose cone(propellar cone?) and put cheater holes in the bottom to make it looks scale.
Goals:
1) Build super light to see if 64's will fly it.( How about Mach .0001)
2) Address wing and nose stress(especially battery location) problems.
3) Getting angles in 3d correct so there is very little twist, warp or whatever.
4) Use my 64 combo(already built, tore apart an old model) and TV to cover a bunch of issues.
5) Find out if short ducting changes has any effect.
History:
Designing past models of exploring ducting, "thrusters", using 2D thrust vectoring nozzles, leading edge devices have yielded tons of info that I am going to use. Will it work?, don't know, but I am going to try.
One- Decided to scale my SR-71 and move EDF's aft from CG (present is area of the neck) so it can be move the battery closer to reduce stresses on neck.
Two- Thrust angles are going to be very important for this plane so I added the TV gimbal in which I am going to tape and explore what is the best angle to use if needed.
When I built my Viggen in the user group, I used the TV nozzle to trim the nose down condition from the canard's +10 degrees to an end product of no angle of incedence to make it fly enen faster. Good way to handle the SR-71. Does it need 2-3 degrees down according to drawings?
Three- When I saw (kilroys07) pringle cans stacked, wow the length for 70's, does it loose power and how much? So I decided that my EDF,thrust tube,and gimbal setup will be 13" long.
This gives me 2 choices-- I now can add the inlet length (6" to cover the front, nose cone and cheater holes) after it flies to see if it looses too much power or now install a pair of 70's by enlarge slot and install new circular tube. No need to build another.
Four- like all experimental planes, it's nickname is bluebird due to the FFF.
I wish to thank kilroy07 for the scale model of the SR-71 which I picked off the ratio and angles and the pringle can picture that got me to move the position of the EDF's.
View attachment 149691
Here is the front and back end on my 13" setup in which I now go to scale it. Being old school, will have to do this project on paper so the size and scale looks good.
Goals:
1) Build super light to see if 64's will fly it.( How about Mach .0001)
2) Address wing and nose stress(especially battery location) problems.
3) Getting angles in 3d correct so there is very little twist, warp or whatever.
4) Use my 64 combo(already built, tore apart an old model) and TV to cover a bunch of issues.
5) Find out if short ducting changes has any effect.
History:
Designing past models of exploring ducting, "thrusters", using 2D thrust vectoring nozzles, leading edge devices have yielded tons of info that I am going to use. Will it work?, don't know, but I am going to try.
One- Decided to scale my SR-71 and move EDF's aft from CG (present is area of the neck) so it can be move the battery closer to reduce stresses on neck.
Two- Thrust angles are going to be very important for this plane so I added the TV gimbal in which I am going to tape and explore what is the best angle to use if needed.
When I built my Viggen in the user group, I used the TV nozzle to trim the nose down condition from the canard's +10 degrees to an end product of no angle of incedence to make it fly enen faster. Good way to handle the SR-71. Does it need 2-3 degrees down according to drawings?
Three- When I saw (kilroys07) pringle cans stacked, wow the length for 70's, does it loose power and how much? So I decided that my EDF,thrust tube,and gimbal setup will be 13" long.
This gives me 2 choices-- I now can add the inlet length (6" to cover the front, nose cone and cheater holes) after it flies to see if it looses too much power or now install a pair of 70's by enlarge slot and install new circular tube. No need to build another.
Four- like all experimental planes, it's nickname is bluebird due to the FFF.
I wish to thank kilroy07 for the scale model of the SR-71 which I picked off the ratio and angles and the pringle can picture that got me to move the position of the EDF's.
View attachment 149691
Here is the front and back end on my 13" setup in which I now go to scale it. Being old school, will have to do this project on paper so the size and scale looks good.
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