A V-2 rocket with wings.

quorneng

Master member
This was my first serious attempt at a scale VTO (note no L!)
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Right at the end of WWII Von Braun wanted to extend the range of the V-2 by adding wings so it could glide an extra 120 km.
Using lightweight Depron construction I judged a single 70 mm EDF in the tail with big air inlets between the fins would have a sufficient excess thrust from an 1800 mAh 4s to take off vertically. Although drawing 46A would work the 1800 mAh battery very hard once at altitude it would need so little thrust to fly as a conventional plane it would be able to cruise around for some time. It had a 3 axis gyro not to hold the vertical but to reduce the rate of any upset.
It worked surprisingly well and made a number of flights.

However the EDF was not really rated for 4s and slamming on full power stressed the blades so eventually a couple 'let go' just as it lifted off.
It rose to about 7 m, arced over and dived in.
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The nose damage I could easily rebuild but the rear damage around the EDF was much more difficult as the structure around it was very highly stressed. It had been built first with the rest of the airframe built up from it.
After 2 years in limbo this winter I decided to try a different approach. I had flown a couple of scale airliners using racing drone motors (Emax RS2205) with 3 inch 4 blade as ducted props. Nothing like the thrust of a 70 mm EDF but then nothing like the amps or weight either.
The RS2205 can generate over 1kg of trust with a 6s for short periods so I decide to use a 4" four blade with a 5s. It only draws 12A so a much smaller battery can be used. Overall the new motor/battery/ESC combination would save of about 240 g off the original 750g ready to go.
The wrecked 70 mm EDF removed.
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The RS 2205 and 4x3.5 four blade in its duct.
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Now virtually complete with a new nose.
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It uses a tiny 450 mAh 5s battery.
It weighs exactly 555g all up.
Now we just need the Covid 19 rules to be relaxed and the right weather.
 
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quorneng

Master member
first a video of it taking off in its original EDF configuration.
No flight yet but a short test indoors using a 1000 mAh 4s to show it produces more thrust than its weight.
With the intended 850 mAh 5s it should have an even bigger reserve of thrust, provided the prop can stand it.