Official Freewing 64mm Lippisch P.15 Thread

[oefranz]

Nice!

[MeyerVW]

I finally did it. Got the runcam onto the aircraft. Enjoy.

[SanExup]

AndrewF Ahh crap!

[AndrewF]

Well guys, I think I’m just not meant to fly one of these lol I put 3 batteries through it with no issues. But on the fourth one I went vertical, pulled a little power out, went to push the nose back down and it got into an unrecoverable spin. Not sure if I did something wrong, or if it was due to the extra wing loading from the xfly fan and a 4s pack. I check the CG before flying and it was right where the manufacturer suggests.

I thought for sure the battery was going to light on fire, but so far it hasn’t. Currently it’s in an ammo can in my garage until I can dispose of it.

[AndrewF]

Did you have to add weight rearward to balance it?

No, the new fan is heavier than the stock one. With the 2200 all the way back in the compartment, it was right at the suggested CG

[SanExup]

Did you have to add weight rearward to balance it?

[AndrewF]

Unfortunately I'm out of town for a few days, so I can't give you a measurement. But it's the intersection of the wing joint and the panel lines, which I think is the manual's CG if I'm remembering correctly. I balance upside down. And I do use the 4s 2200 as I stated, kind of wedged with the rear of the battery up off the ply plate and velcro at the front. I trimmed the canopy to both fit the battery and hold the front edge. It definitely ugly's up the canopy but is functional. It's so fast and small I don't notice. I'm sure I'll eventually get another lippisch and do a better job somehow to fit the 2200 and not cut the canopy. Man I wish they'd make a bigger version too! So fun!

I have some 2200 4s packs that fit without cutting the canopy. I ended up cutting mine anyway to fit my
gps speedometer.

[SanExup]

Unfortunately I'm out of town for a few days, so I can't give you a measurement. But it's the intersection of the wing joint and the panel lines, which I think is the manual's CG if I'm remembering correctly. I balance upside down. And I do use the 4s 2200 as I stated, kind of wedged with the rear of the battery up off the ply plate and velcro at the front. I trimmed the canopy to both fit the battery and hold the front edge. It definitely ugly's up the canopy but is functional. It's so fast and small I don't notice. I'm sure I'll eventually get another lippisch and do a better job somehow to fit the 2200 and not cut the canopy. Man I wish they'd make a bigger version too! So fun!

[AndrewF]

AndrewF Condolences on the nose but it looks fixable! You're using the 4s 3200kv rated Xfly fan unit?

I did follow some others and programmed a touch of up elevon on a switch for easier hand launching.

yeah, the 3200kv. I already got the nose back together, a little foam tac goes a long way. I had someone else throw it, but they threw it almost straight up so it kind of turned into an uncontrolled rocket lol
Where do you run your CG?

[SanExup]

AndrewF Condolences on the nose but it looks fixable! You're using the 4s 3200kv rated Xfly fan unit?

I did follow some others and programmed a touch of up elevon on a switch for easier hand launching.

[AndrewF]

Maidened the xfly P.15 today. First flight was fairly smooth once it got trimmed. It’s an absolute rocket with the new fan, I did one high speed pass where I went full throttle for maybe 2 seconds and it hit 105 mph, straight and level. Sadly on the second launch it got a little Wild, breaking the nose off. I was flying with a 1800 mah 4s pack with a timer set for 3:00, it came down with 50% left. Most of the flight was done with 1/4 to 1/2 throttle.

I should add, all up weight was 560 grams, I did a static thrust test and it produced 895 grams.

[SanExup]

Or you could go with 4s stock power. Modify the bottom canopy and angle the battery upwards at the rear of the pack.

[Louierc]

Alpha - what is the best go-faster option for the Lippisch ? I have found a 3S 3900 kV 11 blade fan with a claimed 1180 gms of thrust. 4S is an option, but battery space and weight must be a consideration for this model. Any suggestions ?

[AndrewF]

Hand launch is easy peasy. Here's mine, all stock except cheaters are blocked off.

That was smooth. I’ll have to give that a go. I was just reading about blocking off the cheater holes, I’m glad I did. From what I see it helps a lot.

[davecee]

Got the Xfly 4s fan fitted. It just took some carving around the inlet ring. I will hopefully maiden it today, fingers crossed.

Is there anyone here who flies with the landing gear? I’m not a fan of hand launching, but I’m worried the landing gear will hurt performance.

Hand launch is easy peasy. Here's mine, all stock except cheaters are blocked off.

[AndrewF]

Still with the stock ESC?

No, I swapped in an E Flite 40 amp

[Jake Bullit]

Got the Xfly 4s fan fitted.

Still with the stock ESC?

[AndrewF]

Got the Xfly 4s fan fitted. It just took some carving around the inlet ring. I will hopefully maiden it today, fingers crossed.

Is there anyone here who flies with the landing gear? I’m not a fan of hand launching, but I’m worried the landing gear will hurt performance.

[Jake Bullit]

Has anyone run on li-ion either 3s1p or 4s1p? Will it fit without carving ,typical dimension of 4s1p is 38x38x70mm or 36x36x70 for 3s1p.

[AndrewF]

If I still had mine, I'd do it just for the giggles and to get a change of shorts. I was in science for 20 years. It's sometimes over-rated. Yes, I have 1800, 4s LiPos that weigh about the same as my 2200, 3s (and same dimension, too).

My thoughts exactly. I’ll be sure to post some pictures/videos once I get it done.