Aero L-39 Albatros V2 - EDF Jet

[Oldrover TJ]

Well I have some sad news. My L39 Mk I is no more. I think it got to hot on the way to the field and all the glue joints failed. I could fix it but I'm thinking Mk II with the rudder and more battery tray support needs to be sped up. However I'm going to use gorilla glue so it's definitely not an evenings worth of work.

 

[jfaleo1]

Awesome, sounds good! Also, roughly how long is the flight time for the EDF version (50mm and 70mm)?

Depends on the battery. 3000MaH 4s 45C got me about 4-4.5 min at mixed setting on the 70mm about 3 at mostly high throttle.

 

[Matthew Sanders]

@Grifflyer Could you please send me the 70mm plans to this airplane? I have a spare EDF that needs a home...

 

[Grifflyer]

Check your inbox

 

[Matthew Sanders]

Check your inbox

Thank you very much!

 

[Matthew Sanders]

By the way, what battery is suggested for use in the 70mm one? And how much flight time do you get?

 

[Oldrover TJ]

I use a 3000 and 3600 mah 50c 4s with an FMS 12 blade fan. I get about 3 and 3.5 minutes respectively.

 

[Matthew Sanders]

I use a 3000 and 3600 mah 50c 4s with an FMS 12 blade fan. I get about 3 and 3.5 minutes respectively.

So a 3300 4s 80C will work for about 3 minutes and 10 seconds-ish. Was there much difference in battery placement between your 3000 and 3600?

 

[Jordan3367]

Yo, I'd love to try the 70mm version, if someone could send the plans my way (or post them here) that would be amazing.
This plane looks incredible.

 

[jfaleo1]

Yo, I'd love to try the 70mm version, if someone could send the plans my way (or post them here) that would be amazing.
This plane looks incredible.

Send a message to @Grifflyer and I am sure he would share. I am not comfortable sending them without his approval. It is awesome.

 

[Grifflyer]

Send a message to @Grifflyer and I am sure he would share. I am not comfortable sending them without his approval. It is awesome.

I've already sent them, and for the future I'm perfectly fine with you sending the plans to people.

 

[Guy S.]

This is a uneducated guess but I think having the EDF toward the middle of the airframe, with a relatively long thrust tube helps it sound that way. I View attachment 169755
I just put a similar setup in a FT Viggen and it doesn’t sound nearly as cool. The fan on the Viggen is the higher pitched version, and it’s mounted much farther back, with a short thrust tube. It has more electric motor sound, and a lot less whoosh.

I’m pretty sure now that the sound of my printed EDF is due to insufficient flow straightening. I put a more aggressive pitch fan, and changed from a 2206 to a 2408.5 with similar kv. Now it’s little more than a really slow sound machine. It’s drawing plenty of amps, and making a lot of noise but not really moving the air out the back. Pretty sure it’s just swirling around inside the duct and thrust tube. On to version 4.

 

[jfaleo1]

I've already sent them, and for the future I'm perfectly fine with you sending the plans to people.

Thanks

 

[Jordan3367]

Two videos featuring this beautiful plane:

The first one has some audio and HD glitches, the second has some weird keyframe mistimings on the zoom effects, I'll likely be reuploading them soon but I figured I'd share them anyway.

 

[Grifflyer]

Two videos featuring this beautiful plane:

The first one has some audio and HD glitches, the second has some weird keyframe mistimings on the zoom effects, I'll likely be reuploading them soon but I figured I'd share them anyway.

Wow!! That's some AMAZING footage you got!!!

 

[Jordan3367]

Thanks!

The plane flies really well and looks fantastic, my brother's feedback is this - the nose and the wing are both fairly fragile when unexpectedly encountering the ground, (as with most foamboard planes), so a better spar (we used a thin metal one) and some internal supports on the nose through the midsection helped a lot with the durability. I dunno if you caught this, but in that first video the spar actually broke midair, it was "softened" a little earlier in a few crashes, but after adding a better spar it was never a problem again. Great plane, we will definitely be fixing this one up and flying it again.

 

[Grifflyer]

Thanks!

The plane flies really well and looks fantastic, my brother's feedback is this - the nose and the wing are both fairly fragile when unexpectedly encountering the ground, (as with most foamboard planes), so a better spar (we used a thin metal one) and some internal supports on the nose through the midsection helped a lot with the durability. I dunno if you caught this, but in that first video the spar actually broke midair, it was "softened" a little earlier in a few crashes, but after adding a better spar it was never a problem again. Great plane, we will definitely be fixing this one up and flying it again.

Yeah I saw that, did it fly better with the dihedral? I'm very happy to hear you're enjoying this plane!!

 

[Jordan3367]

Yeah I saw that, did it fly better with the dihedral? I'm very happy to hear you're enjoying this plane!!

Heh, I don't think so, it was loosing too much aileron control and lift. I noticed from the quad before he did haha, I was like, "uhhhh hey your wing's about to come off... you should probably land as soon as possible." It took remarkably little damage on that landing.

 

[Cycle Pilot]

I’m almost finished with this build but I’m at a loss on the turtle deck. I’ve read all 17 pages and I read the description on about page 7. Does anybody have any pictures of the process they can share? What I don’t understand is the turtle deck piece seems too big especially towards the aft. All the pics of planes I see looks like the turtle deck comes to a point and is way shorter than the printed piece I have. For the life of me, I can’t figure it out.

 

[Grifflyer]

I’m almost finished with this build but I’m at a loss on the turtle deck. I’ve read all 17 pages and I read the description on about page 7. Does anybody have any pictures of the process they can share? What I don’t understand is the turtle deck piece seems too big especially towards the aft. All the pics of planes I see looks like the turtle deck comes to a point and is way shorter than the printed piece I have. For the life of me, I can’t figure it out.

Do you have a picture of your issue? That might help us figure it out.