nice job Dave!

Christan

Hinges only just tacked with CA at this time

Dave

Yes ... if all is ok then you glue with epoxy

i'm installing brake valve (AIRPOWER EV1-U)

Christian

Yes, just a bead around the edge to position it. Even the CA is enough, but the epoxy helps re position the hinge should the door get knocked off

Dave

I see the vampire at FLJ2011 few seconds in youtube video...
there are another video with complete flight including take off and landing?

Pneumatic system for gear and brake done..

now i will finish radio set

link to vampire walkaround
[link]http://www.cybermodeler.com/aircraft/vampire/vampire_walk.shtml[/link]

I also have a DerJet Vampire and now have 10 flights on it, this is a good flying model, and really is becoming a fun airplane to fly now that I have it close to dialed in. First off, my Vampire came out at 31 3/4 pounds with the necessary nose weight in place. Power is a Jet Central Rabbit, 20 pounds of thrust, great combination, got off the grass field at Florida Jets with no issues, and top speed is well above that necessary for scale flight.
Thought I would pass on some flight setup info for the next guy to aide in dialing in their model quicker. I have flown it from with the Center of Gravity as measured from the rear edge of the front spar blade from 15mm aft to 30mm aft, I like it best at 15mm aft and would strongly suggest don't bother trying to fly her at 30mm aft, it rotated way to early on takeoff and left me really slow, had to do that pilot stuff to fly out. At the 30mm aft CG the use of full flaps really left the Vampire gliding at a real slow speed so I chose to land it at half flaps, it handled well, but a bit pitch sensitive during the landing flare. With the 15mm aft CG it takes some elevator to rotate on takeoff, and use of full flaps is comfortable on landing with no flap-elevator mix required, and the pitch control for final flare is very linear, makes those smooth landings pretty darn easy, this is where I have settled at for now, and it has taken 1.6 kg's of nose weight to get this CG.
Control throws, man what a surprise, this model doesn't need much control throw to be responsive. I am flying at +/- 15mm throw with only 3% expo on the elevator in low rate, and never change out of low rate for the whole flight, very smooth flying with enough control throw for a full flared landing with the flaps fully extended when landing. No flap to elevator mix has been found to be necessary. The ailerons, well, I was surprised how little throw again is necessary, I am flying at +/- 10mm at 15% expo, some people may find maximum roll rate a little slow but this setting makes for some real smooth scale type flying, I like this setup. Rudder throw is now at +/- 25mm, but I have yet to get in to any knife edge trimming yet, so when the weather breaks up here in NorthEast Ohio I will explore this and report on the mixes for best results.
One surprise with the Vampire, I ended up with an aileron to rudder mix do to adverse yaw with aileron application, I am flying the Vampire without a gyro on yaw. I have found 15% mix, or about 2mm of rudder movement in the direction of full aileron application does a good job of eliminating most of the adverse yaw. Again this issue is reduced with the forward CG, but overall I think I will be adding a gyro on the rudder as it does dance around a bit in yaw in turbulent air.
Hope this helps the next guy setting to fly their Vampire, it sure looks good in the air.
Jim Hiller

Jim

Great notes that I'm sure will help everyone getting their Vampires ready.
Have you not tried aileron differential rather than the rudder mix? Or does it roll axial with = aileron travel?
I have flown a few Vampires and with the "fat" fuselage and small fins, a rudder gyro has always been a good idea.

regards

Dave

Dave,
Didn't get a chance yet to try out additional aileron differential, looking forward to trying that path also, along with a gyro. I have only seen one full-scale Vampire fly, and the pilot told me she was a rudder airplane, so not surprised when the model is similar, usually is. What I need with this bird is more than 9 channels so I can dial in all these ideas, I would like to put the two ailerons on different channels, and a rudder gyro with programmable gain for gear up versus gear down setting. It's a long summer, so look forward to trying out some ideas when the weather breaks.
Jim

Jim

I'm running a DSX-12 so have channels for each control. Already set differential on ailerons from a hunch, I've set more than you at 16mm up and 12mm down aileron, but with 25% expo figure. I'll see when I fly it, but I normally get close on the first flights to the way I like models dialed in.

We should have better weather by the time she's ready also.

Dave

Back on the Vampire.
I managed to get 5 1/2 oz of lead in the nose void, all helps. I will also place the UP3 valve in the nose next to the nose unit 2.4oz! I knew from the start that a lot of weight would be needed but jetmodeler has made me think even more radical.
Typical DerJet door shut lines!
Nose steering servo.

why Dave?

Christian

You have lost me! Why what??
The door shut is normal on most models with gear doors.

Dave

I think he means the packers under the retract?

Gregg

yes..the wood spacers under the front gear base

chriqui:

Retracts worked perfectly at FJ. . . .UNTIL the sand and loam reached the side plates. This collection of sand prevented the gear from working correctly. Until this collected, gear worked purrfect !

Eric Clapp
DerJet USA

The packers are something I always do. They are light ply. There is no 100% guarantee that the mount is flat, it only has to be twisted a little and it loads the retract frame up. By using light ply, this will give slightly if there is more pressure from one corner than the others. This reduces any chance of binding.

Dave.

OK....thx to all

yesterday i finished to made cable servo connection...now ready to connect to emcotec
n.1 channel for n.2 rudder + steering
n.1 channel for n.4 flap with jr magicbox

Yes I did have some issues with the retract units at Florida Jets, they worked good here at home on our paved field, but then lesson learned at Florida Jets, newly machined fits don't work well when the sand kicks up and gets in the workings. I have broken the edge on the slot as the retract pin travels over the sharp edge coming off the lock position, up and down. I expect this should solve my problem, it has worked before for me when flying off grass fields. This photo shows the sharp edge, and just how little is removed to free up the travel, do both edges coming off up lock and down lock positions.

Jim

Jim

Already did that on my units, std practice for me to de burr and de-sharpen everything. This is such a sharp change in direction I spotted that early. Its in my build manual notes.
We don't get the extreme temps or dry grit like you guys though!

Dave

After a surprisingly busy week, I've finally completed the nose door. The two ribs were a little wide for the clevis provided, so I used a Dremel to thin them in the area they swing through. I had to fill in the air holes with Aeropoxy. System works well, fiddly job though

Dw

Pixs if it worked

Oh for a 36 hour day...
So, started looking at the install now the mechanics are done. The nose steering servo works the same way as the rudders, so a single channel could be used.
Tanks dropped in.
Turbine mounts are dual notched to allow for a range of turbine diameters and length.

Dw

like me... 1 ch for rudders and steering

the work proceed on flap , aile, airbrake travel adjust