Light weight EDFs
03-10-2025 | 02:23 AM
#1
Thread Starter
Light weight EDFs
If you build in foam and it do means build your "jet" can be a lot lighter. This poses the question if the full size uses a huge turbo fans does it actually need an EDF?
I was this problem when I considered building an Depron Airbus A350.
At the scale I intended the nacelles would allow a 76mm (3") fan. A commercial EDF at that size would be far more powerful and more to the point heavy than I needed so would a ducted prop provide a solution?
Multiblade quad props of the the required size are cheap and available in left and right hand. As another advantage props at lower power are far more efficient at converting Watts into thrust.
To cut a long development short this is what I ended up with.
1.5m span. The nacelles and pylons are 3D printed including suitable mounts for the Emax 2805 quad motors that drive four blade 3x4.5 quad props.
Only the flying surfaces have any reinforcement and its just balsa flanges to the spar.
No undercarriage as it is hand launched and belly lands. It weighs 585g (21oz) ready to go.
The relative efficiency of using ducted props is show the it uses just a single 1000mAh 4s LiPo.
It flies nicely as too. A short edited video.
Not a simple build but the result was worth the effort and I still have it 5 years later!
I was this problem when I considered building an Depron Airbus A350.
At the scale I intended the nacelles would allow a 76mm (3") fan. A commercial EDF at that size would be far more powerful and more to the point heavy than I needed so would a ducted prop provide a solution?
Multiblade quad props of the the required size are cheap and available in left and right hand. As another advantage props at lower power are far more efficient at converting Watts into thrust.
To cut a long development short this is what I ended up with.
1.5m span. The nacelles and pylons are 3D printed including suitable mounts for the Emax 2805 quad motors that drive four blade 3x4.5 quad props.
Only the flying surfaces have any reinforcement and its just balsa flanges to the spar.
No undercarriage as it is hand launched and belly lands. It weighs 585g (21oz) ready to go.
The relative efficiency of using ducted props is show the it uses just a single 1000mAh 4s LiPo.
It flies nicely as too. A short edited video.
Last edited by Quorneng; 03-10-2025 at 02:26 AM.
03-14-2025 | 12:42 PM
#2
Thread Starter
Taking lightweight EDFs to the extreme is a VTO.
Right at the end of WWII Von Braun added wings to a V-2 so it could glide and extend its range. Tw owere actually built and flown in late 1944.
Could I make an RC EDF version take of vertically?
It took a bit of development but ended up with.
All made of 3mm Depron sheet..A 70 mm EDF in the tail with 4 big cheat holes between the fins with a 4s LiPo right in the nose for balance.
It has a gyro but set to rate only so no "hands off" stability to allow it to convert to normal RC flight and a belly landing.
.
The torque of the EDF is such that it spirals in the climb. Un expected but at least it keeps it pointing more or less straight.up.
It flies om much reduced power so can cruise for a reasonable time..
Right at the end of WWII Von Braun added wings to a V-2 so it could glide and extend its range. Tw owere actually built and flown in late 1944.
Could I make an RC EDF version take of vertically?
It took a bit of development but ended up with.
All made of 3mm Depron sheet..A 70 mm EDF in the tail with 4 big cheat holes between the fins with a 4s LiPo right in the nose for balance.
It has a gyro but set to rate only so no "hands off" stability to allow it to convert to normal RC flight and a belly landing.
The torque of the EDF is such that it spirals in the climb. Un expected but at least it keeps it pointing more or less straight.up.
It flies om much reduced power so can cruise for a reasonable time..
03-14-2025 | 01:22 PM
#3
Thread Starter
Taking lightweight EDFs to the extreme is a VTO.
Right at the end of WWII Von Braun added wings to a V-2 so it could glide and extend its range. Tw owere actually built and flown in late 1944.
Could I make an RC EDF version take of vertically?
It took a bit of development but ended up with.
All made of 3mm Depron sheet..A 70 mm EDF in the tail with 4 big cheat holes between the fins with a 4s LiPo right in the nose for balance.
It has a gyro but set to rate only so no "hands off" stability to allow it to convert to normal RC flight and a belly landing.
.
The torque of the EDF is such that it spirals in the climb. Un expected but at least it keeps it pointing more or less straight.up.
It flies om much reduced power so can cruise for a reasonable time..
Right at the end of WWII Von Braun added wings to a V-2 so it could glide and extend its range. Tw owere actually built and flown in late 1944.
Could I make an RC EDF version take of vertically?
It took a bit of development but ended up with.
All made of 3mm Depron sheet..A 70 mm EDF in the tail with 4 big cheat holes between the fins with a 4s LiPo right in the nose for balance.
It has a gyro but set to rate only so no "hands off" stability to allow it to convert to normal RC flight and a belly landing.
The torque of the EDF is such that it spirals in the climb. Un expected but at least it keeps it pointing more or less straight.up.
It flies om much reduced power so can cruise for a reasonable time..
