Sacrilege I know - but 50mm EDF conversion to prop

[solentlife]

Lets ignore the Pusher part ... and see what would be a good combo for example to convert a 50mm EDF T45 to prop ?

High kv + small prop or larger prop on lower kv ?

Pusher or tractor prop ?

Any ideas anyone ?

Nigel

[pmullen503]

Pusher will probably look better. The tricky part could be the CG. Not only will the weight of the motor be closer to the ends (which ever end you choose), but you should be able to use a lighter battery as well.

I'd go with a high KV motor, small prop. Wattage maybe 1/2 to 3/4 of your EDF.

I've done the opposite, converted a pusher prop jet to EDF. EDF to pusher will probably give you a lighter, better flying plane.

[solentlife]

What prompted this thread was a guy on RCG who converted his T45 to tractor prop. He did it because of noise complaints.
Years ago - I had a tractor prop Mirage 2000 and same people marketed a Red Arrows Hawk.

CoG .. I would imagine would be OK ... as a pusher prop would be lighter than an EDF unit but further back. Lets say in moment arm - equal. Therefore as you say - the battery pack copuld be smaller but pushed forward ... as is now with the EDF ... balancing out. On the F16 - it would probably solve the issues that one has with too small a battery area.

If you do a tractor prop (that is prop on the nose) ... as the older ones I mention above ... the battery pack can be carried back where the EDF unit went or in the duct. Probably easier to balance than a pusher. Use of a decent spinner and in right colour - once motoring - you'd never know ...

Launching ... pusher props lend better to catapult launchers than tractor.

Final ? ... which would be faster ? Tractor or pusher ? Which is more manoeuvrable ? Which will have better control at slow speed ?

I initially answered the other guy that I didn't like the conversion ... but more I ponder it ... more it intrigues me.

Nigel

[solentlife]

The main question then remains :

For a ~400gr 50mm Mini Jet airframe, what motor, what prop ?

I think it may need a bit more oomph than initially thought. The prop size as well if pusher would need to overcome the fuselage size, even with the air from duct. If tractor - then it's usual to have larger prop anyway.

So I'm thinking maybe a 7x5 or 7x6 prop on a 1800kv motor ? Maybe more ?

Any ideas ?

Nigel