Double Knockoff - Grifflyer GrunJet/ Ben Harber BDF.

[chris398mx]

I wanted to try a BDF, but they are not released yet, so I thought I would try my hand at making my own with a little inspiration from other forum members.

So here is my first attempt at a BDF style power plant ready for maiden hopefully tomorrow morning.

 

[chris398mx]

Reserved for Maiden

 

[Grifflyer]

Can't wait to see it fly!!

 

[evranch]

I like it, it looks pretty beefy on there. Looking forward to seeing it in the air!

 

[chris398mx]

It Lives. I flew it this morning. Cruises at about 40% throttle Should have about 7 minute flight time cruising with short bursts of full throttle. Sorry no video. I didn't have anyone to film and it was a last minute decision to take it up before I left for work. It was pretty windy to get a feel for the stability, but it did slow down pretty nicely for landing. I will try to get some video next time I take it up.

 

[whackflyer]

I wanted to try a BDF, but they are not released yet, so I thought I would try my hand at making my own with a little inspiration from other forum members.

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So here is my first attempt at a BDF style power plant ready for maiden hopefully tomorrow morning.
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What's your prop and motor specs?

 

[chris398mx]

1. 4052 3 blade props. https://www.amazon.com/gp/product/B0796S5YLM/?tag=lstir-20
2. EMAX RSII2207 2300KV Brushless Motor CW Thread 3S 4S for 210 220 250 FPV Racing RC Drone Quadcopter Frame (RSII 2207 2300KV) https://www.amazon.com/gp/product/B07LCYWZ7J/?tag=lstir-20
3. 1300 4S 45C battery.

 

[The Hangar]

It Lives. I flew it this morning. Cruises at about 40% throttle Should have about 7 minute flight time cruising with short bursts of full throttle. Sorry no video. I didn't have anyone to film and it was a last minute decision to take it up before I left for work. It was pretty windy to get a feel for the stability, but it did slow down pretty nicely for landing. I will try to get some video next time I take it up.

Sweeet! What size is the fan - 50 mm??

 

[chris398mx]

The props are 4 inches so about 102mm

 

[The Hangar]

The props are 4 inches so about 102mm

Ok, I see - thanks!

 

[chris398mx]

@Grifflyer Here is some video of your GrunJet with my version of the BDF.
Flew for about 3 minutes total and had 51% battery left. It really slows down nicely for landing.

Video1 take off

Video 2

Video 3. My son caught the plane for me during landing so it didn't even see any snow.

 

[Grifflyer]

@Grifflyer Here is some video of your GrunJet with my version of the BDF.
Flew for about 3 minutes total and had 51% battery left. It really slows down nicely for landing.

Video1 take off

Video 2

Video 3. My son caught the plane for me during landing so it didn't even see any snow.

Wow, that was flying really nice! It looked like it had tons of power!!

 

[The Hangar]

Wow, that was flying really nice! It looked like it had tons of power!!

You think I could put one of these in an X-29?

 

[Grifflyer]

You think I could put one of these in an X-29?

I don't know the Grunjet is a pretty small plane compared to the X-29...
What's wrong with running it as a pusher setup?

 

[The Hangar]

I don't know the Grunjet is a pretty small plane compared to the X-29...
What's wrong with running it as a pusher setup?

True. There’s a ton of torque roll...

 

[chris398mx]

I think I am going to put my BDF in a Viggen and see how she does. I will have to do some scaling to get it to fit, but let see if she has enough power to be a good flyer. Does anybody see why it shouldn't work?

 

[The Hangar]

I think I am going to put my BDF in a Viggen and see how she does. I will have to do some scaling to get it to fit, but let see if she has enough power to be a good flyer. Does anybody see why it shouldn't work?

That'll be cool!