maybe C/N could comment on that he has flown both

The sapac viper jet's problem is the wings are built wrong, they have no washout and no vert winglets. It's not a very stable aircraft at slow speeds, especially with the flaps down at all. Also, it's pretty big for a 70 mm size jet.

this one looked stable on landings ,i built some washout into it ,i did not use a lot of incedence as i went for less drag at speed but it seemed to fly nice ...i wish brent would pipe in with his thoughts.

to be honest, i really like the way the sapac VJ flies, both of gary's fly freakin sweet. we use about 40 deg of flap for landing, and it really comes in nice i think. last couple flights i made with garys i got off the power a little soon resulting in a not so soft landing, but overall i really like the VJ. the F-20 is a very smooth flyer, you must use flaps (about 30 deg max) for landing, and you have to land it like a real jet. power on, nose high. there isnt much glide with the gear and flaps out, you have to stay in the power as the flaps are quite big. the model tracks really well though, and there is no tip stall, just mush. its especially smooth in pitch, unlike many full flying stab models which seem to hunt in pitch. i just realized i never tried to knife edge the F-20, but im willing to put money down that it does it quite well. we'll have to try that the next time out. the model needs to be setup with the nose high on the ground to help it rotate, since the gear are in the scale location and well behind the cg. it flies really nicely, you can see by the maiden video that after a couple clicks of trim, i felt instantly at home with it. those who buy it just need to realize its not a sport jet with a huge wing. the wing loading is a little high, so you just need to be prepared for landings a little on the warm side. id really like to try the model on a light weigh 800W setup, i think that will make the landing much much nicer, and it should still do every bit of 115-120 on 850w. it did before, no reason it still wouldnt. overall, i was very happy with the F-20, it flies much like the many F-5 family models ive built and flown. honest, fast, and smooth. i certainly wouldnt get crazy on the power systems, i think once you get over 5.25 lbs, the model starts loosing the fun factor as the WL starts getting out of hand. we were flying it at just over 5 lbs, and it was great, but i wouldnt want to get it much heavier than that, its a scale model, and the wing area just isnt there for anything more than that. i think anybody who has successfully flown a habu 32 or a sapac viper or L-39 would have no problem flying this model.

Gary do you have any more vid? did you ever do a doppler ?

Originally Posted by AIR SALLY

Gary do you have any more vid? did you ever do a doppler ?

No Doppler jet. . I've been swamped since Vegas.

Just got in from Best in the West. I'm beat.

Yeah I got more video.

i know the feeling

Originally Posted by efflux RC

No Doppler jet. . I've been swamped since Vegas.

Just got in from Best in the West. I'm beat.

Yeah I got more video.

The F-20 make an appearance at Best in the West as well?

Originally Posted by jayb1rdz

The F-20 make an appearance at Best in the West as well?

No. A.S. has the jet, and he and CN were unable to attend.
The F-20 will fly next at "The Big Jolt" in two weeks.

Here's some pics from the BITW event. More coming.
http://www.rcgroups.com/forums/showt...4#post23062720

Rodger,

I get 107mph on 4s @72*F for the L-R pass at 0:57
As shown in my Habu video there was vitrually no wind (maybe 1-2 mph)during the flight.

efflux RC / Air Sally......F-20 raw video (3 min 33 sec)

Gary, ive got a 70mm power system that can do 3-4000 watts. but in this f-5 will start with 4 cell, so 1500-1800 watts maybe. When is it out? Im selling of planes to raise funds. Lee

this will fly real nice on just 1500-1800 watts ,trying to keep the weight at or below 5lbs. hope to start on the beta airframe and to get the wood parts lazer cut.

Hi Lee,
We still have the wood parts and control arms to get made. I believe Rodger stated that the first ones will be available after the first of the year.
There are 7 units spoken for, and a few on the waiting list ahead of you.

EDIT:
........
You beat me to it Rodger.


Hey I got the carbon fiber mains doors you made me from my pattern installed on the 10s Habu.
No finish...just bolted them on natural. They seal against the wing real nice. I'll post some pics tomorrow.

Originally Posted by efflux RC

Hi Lee,
We still have the wood parts and control arms to get made. I believe Rodger stated that the first ones will be available after the first of the year.
There are 7 units spoken for, and a few on the waiting list ahead of you.

EDIT:
........
You beat me to it Rodger.


Hey I got the carbon fiber mains doors you made me from my pattern installed on the 10s Habu.
No finish...just bolted them on natural. They seal against the wing real nice. I'll post some pics tomorrow.

Hi Gary & Rodger,

You may want to inquire with the people supplying you struts and retracts, they used to do laser cutting as well.

- Birger

Thanks Birger, I will.