Dave Bugz

See you there, must remember to "yank harder"

Dave Wilshere

Colin's just dropped in with the 99% complete Viper, 1980grams, just needs the tail pipe!

i3dm

My Feedback: (51)

looking awesome ! cant wait to see this one fly... ive been fantasizing about this combo for some time..
When is the maiden schedualed ?

bigplumbs

That is going to be an eye tester

Dennis

Dave Wilshere

If we get the tail pipes we will try it this weekend...between the storms!

Dave

Didier

Wow, that Viperjet looks awesome. That P-20 seems to be fit perfectly in to to that airframe.

Dave,
Do you have any information concerned the tailpipes for P-20's?
What brand, material used, diameter, weight and ofcourse the price?
Thanks.

Dave Wilshere

Motors & Rotors 0.2 steel 48mm dia, can't remember weight and out of stock till more arrive to weigh.
Can email you lengths and prices if you email me...don't want Dennis getting stressed

Colin Gontier

Heres a pic of the front end of the install. Not much to see really - it was a bit like performing keyhole surgery in there but it all fits, including on board gas. Ive put the ECU and RX pack either side of the tank and CofG is towards the forward end of the recommended range. Once the pipe is in it should be towards the rearward end and with fuel on board spot on I hope.

Have stuck silver tape on the wing LE's to aid visibility but mainly because I left the plane on the living room floor whilst my son's rabbit was in the house and he appears to have developed a taste for balsa. Luckily I caught him as he took the first munch out of the leading edge! There are some things you just cant account for in a build eh [X(]

Dave Wilshere

Bring on the dry weather... Pipes here

Colin Gontier

Pipe now in so obviously the engine had to be started ! It would have flown today but the winds were extremely high and it rained all day []

Hopefully Saturday for the maiden. In the meantime heres a video showing the first start of the little P20. Worked like clockwork.

[youtube]http://www.youtube.com/watch?v=gXkavTVN6YU[/youtube]

Jamie C

Anything wrong with a brush to sweep away the leave's? cheaper too Will be very interested to hear how the test flight went, hope the weather improves.

Pat Barnes

VVVery Nice! I want the blue Hawk!

Colin Gontier

Jamie - Dave claims he was checking for air bubbles - yeah right! You need to get yours built in time for a p20 fest at classic jets in Dec

Pat - all the models in this range should be really good with the P20. We'll soon find out how this one handles. Plane is ready, camera is ready, just need a break in the weather! I reckon it will fly great, just need to see if it lands well.

simonmiller

Very nice!

simon

Dave Wilshere

Colin

Can you bring the 3K leaf blower back today, there is a pile outside the door again

Everything looks good so far, the tail pipe set-up kept the fuselage very cool, I guess the only thing we need other than good weather is short grass!

Dave

bigplumbs

I am cool now just had a beer

bigplumbs

Of the 3 models from top gun I think this is the smaller of them so to get all that lot in I think you did very well indeed and to get on board gas as well was quite a feat. In my view if there were a range of models like this but a bit bigger they would be a real winner for the P20

Dennis

Jamie C

Bobcat 25 arrived this week, going to be modifying it a bit for turbine ops. Will get the P20 up in the air quickly though before it is fitted to the L39.

Colin,
Greatly anticipating your test flight results, will hopefully have the L39 ready by Classic jets.

Dave Wilshere

Ok, the Viperjet has flown, proving the basic concept...

Our grass strip has not been cut in a few weeks and the grass is very long and wet from several days rain. Colin tried taxi tests yesterday in longish grass and found that the oleo leg connection pins (2.5mm dia) were made from toffee and bent really easy, you can bend them straight with little effort. We decided to change the Oleo set up for the wire legs supplied with the kit, partly to give the gear mounts a chance.
The first take-off attempt showed good ground speed, but the wire legs bent back and the Viper showed no attempt to rotate, a late shut down had the VJ off the end of our strip-proving the gear mounts are good! and scuffing the underside.
At this time I noticed the wheel position is a long way behind the balance point-like 1 3/4"-2".
For the second attempt I tried to find the shortest grass and longest run with the legs pre set forward a little...still no rotation, but I shut down early enough to stop and taxi back...legs were already set back a few degrees, seems the wire legs are toffee also!
Further pre set forward and tried again...still no rotation. The VJ sits pretty flat, so in an attempt to get air under her and the wheels near the balance point, I bent them well forward, this had the affect of shorterning them and got them near the balance point...
This time it got off, but in one of those "flicky" yank moments! gear away and only one main went, but a little trimming had the VJ flying fine. It felt good, didn't feel heavy in the air and was happy flying at half power. Nothing fancy was tried as fuel would be getting low now, but a few camera passes that hopefully Paul got then [X(] I put the gear down ready to try full flaps before landing. This was done going up wind over the strip, then all hell broke out! The VJ seemed to flick and fly side ways! We are still not sure what moved but it became a handfull, gyrated around the sky, I got it sorted but flying side ways, then it flicked again and kissed dirt!

Damage was less than I expected, but would still need a new fuselage. The VJ undercarriage obviously needs moving forward, so we are going to look at the other two models-or possibly something else. The wings are wood so maybe we can move the gear mounts forward on another VJ as it looked good in the air and seemed to be OK.
The wing loading is higher than the Baby Cougar, which I flew again today, this larger airframe copes well with grass, so maybe the VJ of a hard surface only.

Dw

Dave Wilshere

Pixs from Paul Baker

Paul0088

Flying shots Pheonix

TUMBLER

My Feedback: (13)

Dave,

Looks like the fuel tank is pretty far forward of the CG. With it fully loaded with fuel, you think that might be why it had trouble rotating?

Brian

Dave Wilshere

Brian

No, balance was set with header full and some fuel in main tank. Defo main wheel position, no been told the EDF needs good ground speed and "leaps" into the air. Gear needs moving forward.

Dave

Colin Gontier

Well it looked good in the air......

Kinda glad I gave it to Dave to do the maiden honours so we can eliminate pilot error (mostly )

I have spent the last few hours giving everything a thorough examination and still no further clues as to why things went wrong. Although the fus is damaged beyond repair everything was still connected and functional. All servos have been checked, all surfaces and linkages still all in one piece even after the impact. No issues with turbine / pipe or mountings. Nothing had moved inside the airframe. To be honest there wasn't any room for anything to move anywhere! Also double checked radio in all switch positions for any rogue mixes and nothing found.

I'm not sure if Dave had full flap in as that is the only flight condition that hadn't been tested yet. We had programmed in a healthy amount of full flap as we felt it would need some good drag to slow it down.

Pat Barnes

Sorry to hear about the jet. Hope you figure out what went wrong and get another back in the air soon. Maybe some crow on the ailerons with flap to help with tip stall characteristics?