jedda747

hollywood alsky

SMBJets

On you Marty...
maiden tomorrow?

M3Baker

Wow, this thing must have a lot of power. How do you like it?

blakeketcham

My Feedback: (61)

Hi, has anyone tried to change the thrust angle to correct the problems with gen 1 versions that do the cobra when you slow down too much? I have made a 5 degree down thrust mount to help push the tail up as you come in? is my idea stupid or do you think this might help. I have flown this three times and managed to save it 2 times in flight when slowing down, it shot up while setting flaps.(stayed high) While landing it did it twice and was flown with a very experienced pilot and he did it also. is there any balance changes that could also help. it is set to the front pin as in the threads. I want fly this but the wait for new booms to make a gen 2 is forever. plus they want 500 dollars. Any insight would help. a Friend said the down thrust is to keep it from climbing at full thro. Mine does not have that problem. I was wondering if the same issue is why the bobcat has a down thrust on it. thanks for you help. Blake

lightningmcnulty

My Feedback: (11)

I don't think changing the thrust angle will help with low speed issues, I flew mine a little nose heavy and that slowed the problem down but the best fix is to get the longer booms, they change the jet completely and its totally worth it

blakeketcham

My Feedback: (61)

thanks for your thoughts on it. guess I wait til next year when they will have them ready.

Dr Honda

My Feedback: (4)

Blake... I was talking with Rich about this... and he said to extend them yourself. It could be done in a couple days, and only cost a few $$$ for glass, and resin.

1) Cut

2) Make an internal "Box" out of lite-ply, that will slide in, and hold them straight.

3) Over glass.

4) Fly without issues.

Peter Koleff

Hi, do you have some details of this procedure, like where to cut and how long to extend the booms ?
Thanks.
Peter.

M3Baker

Peter
The G2 booms are 44 1/2" when measured from the leading edge to the tip of the rudder. This would be the measurement along the bottom of the boom. They are about 15% longer than the first version of the Velox. I promise you with longer booms the jet will not cobra. I've tried and it just won't do it.
Paul

Peter Koleff

Thanks for your information Paul.
I now know that it's necessary to increase the lenght of the G1 booms by 6". But, what would be the best place to cut them ? I guess about 5" behind the wing-tube hole ?

Peter.

blakeketcham

My Feedback: (61)

Thanks all I will do this as this Jet is too squirrely to be my first jet and it is still in one piece. Blake

M3Baker

I don't think it really matters where you cut and lengthen. One thing that you may want to consider is that the boom might be slightly wider along the cut since you will be glassing the seam. With that said, you might consider cutting the booms behind the trailing edge of the fuselage. That way you will still have a tight fit for the booms against the fuselage and wings. Just my opinion.
Paul

blakeketcham

My Feedback: (61)

Well I took everyone's advice and built longer booms. here are some pics of the work and finished aircraft. getting ready to balance the jet. I am guessing there will be at least 6 to 8 oz more up front. the pics of the work show the box I built out of 1/16 ply with a 5/8 basswood inside the sandwich to make it 3/4 thick. there is 1.5 inches overlap inside the booms and I added 8 total inches. I tried to match the angle where I cut the booms by cutting a dart out in the front part to lower the angle to blend to the back. I should have dropped it more as there is a hump. oh well. glassed the outside and did my best to blend but this is my first real project with glassing other than joining a wing. thanks all. hope the weather is good this weekend. Blake

blakeketcham

My Feedback: (61)

here is a couple pics of the work.

blakeketcham

My Feedback: (61)

well did the balance and it needs 14 extra ounces up front. that really sucks. I see in the gen 2 models it looks like the nose is longer, that makes sense.

Dr Honda

My Feedback: (4)

Adding an extra pound to the nose is better than crushing it because of a cobra.

Can't wait to see how it flys.

4ptroll

My Feedback: (35)

Can anyone tell me where the CG location is on the Velox. I just acquired a G1 with the G2 booms on it. I'm also wondering what you guys use for throws on the control surfaces. Any info is appreciated.

Thanks in advance

blakeketcham

My Feedback: (61)

well I balanced mine a 1/8 before the anti rotation pin. as for throws 1/2 flaps 7/8 down 3/8 up elevator. full flaps 1.1/2 down with another 1/8 up elevator. ailerons were 3/4 low rate and 1'" high rate. as you get comfortable you could increase these. rudder all you can get. I fly with 35% expo also. make sure you are well powered, mine weighted 24 lbs dry. and a 18 lb engine is to low in my opinion.

tjrhodes01

wow are you talking about the little one or xl we were flying a k80 on a freind with plenty of umfff my im running a k100 on my g2 and its balistic 200 plus usually most flight is under 40 percent throttle and my dry weight is about 17 1/2 dry

Dr Honda

My Feedback: (4)

Yep... it's the small one.

His is heavy because of an older engine, and some minor repairs. Then... when he lengthened the booms, he had to add a pound or two, to the nose to balance it.

18 Lbs is plenty to fly it... but he fly's off grass, and with how heavy his is... it becomes marginal on hot days.

tjrhodes01

That would be marginal then wow is probably about 26 lbs at take off buddys k80 was also putting out 20 plus lbs even at them numbers it probably still flys great once it gets on pace mine is so clean it dont take much power to keep speed up and it flies on railes

4ptroll

My Feedback: (35)

Thanks for the information. I'm powering mine with a Kingtech K100. I balanced mine at the same location and only had to add 1/2 pound of weight in the nose. All the batteries are in the nose as well. Waiting for a new rudder servo to come in and the it's maiden time.

Peter Koleff

After all your information I finally decided to cut the booms and make the extension. I have cut them as originally planned 5" after the wing-tube hole and made a 6" long extension.
The booms of my Velox are made of composite material with an internal ply wall ending near the point where I cut them. Because of this I had to make an ply reinforcement on the rear side of the cut before making the actual extension. I used hard balsa and 5 layer ply for the extension structure, covered with balsa sheeting and followed by glassing. The whole thing seem to be very strong.I hope the pictures explain it better.
Now i'm waiting for my turbine which is on maintenance.
Blake, where you satisfied with the result of the extension ?
Peter.

blakeketcham

My Feedback: (61)

yes I was satisfied with the extensions I wasn't satisfied with the extra weight. the takeoff conditions that day including temperature and high humidity. the grass was tall there, had the flaps at half and made it pop up. There was 3/8 up elevator mixed in. before I could stay in ground effect is when it got away from me. so with a 27 or 28 pounds plane flying on a 18 pound engine on a hot day made for a bad take off but I'm sure it will work. I am sure it was all me. Needed a clean air frame, gaining speed being underpowered.....

blakeketcham

My Feedback: (61)

Yours looks very nice....