Tony Nijhuis Vampire Build

[David Brown]

Both planes are up to the fitting of booms stage, Wren supplied the jet pipe quickly which is now fitted on Johns plane. We have jigged up my vamp first and fitted the booms which was a testing job with the wires for the elevator plus the closed loop to feed through but all went to plan in the end. Johns will get the same treatment tomorrow and hopefully get them both ready for turbine test by the weekend if I can keep on top of my machine work.

Dave

[David Brown]

Well as before the time just flies by but the models have not to date. Both are now almost ready to test fly ( turbines to run up) but the weather has dampened our enthusiasm as both our flying sites have been too wet to get on. They have both come out at 22.5lb which is due to the additional 2.5lb ballast weight up front to balance them as per drawing. As you can see from the build thread we have mounted all heavy items as far forward as possible, even moved the turbine & tanks 12 mm towards the front. Comparing the installation with the Sterner Vampire the only main difference is that the Turbine & tanks were mounted further forward putting the C of G behind the fuel tank, due to this no ballast was needed. As for flying I had to adjust elevator trim during flight to compensate for fuel being burned off, this should not be needed with Tony's method of installation where the Tank is basically on the C of G.

All the best for the New Year
Dave

[David Brown]

Test run my wren 70 today, sounds great and seems to have plenty of power for the model, we will run Johns tomorrow all being well. Its amazing how a few days of good weather picks you up.

Dave

[DAVE JOHNSON]

Hi Dave--just seen your post about your site conditions---if you get stuck--the offer of tarmac is still there if you want to come and visit to test fly---DAVE

[David Brown]

Still no further forward on the Vamp what with work and the wonderful weather we have been getting, thanks for the offer Dave just not had time to take you up on it.
Dave

[graham trever]

Hello David

I am also building this model and my build is on the winterton forum, I would like to know if you are fitting wheel brakes and what type would they be as there is not alot of room depending on what wheels you have.My Build is at wmfcflyers.freeforum.org. Look forward to any comments and helpful advice.Engine run is on youtube at gtrever78.

Regards

Graham

[David Brown]

I have ordered some sample tires and will be producing my own wheels & brakes to suit if they ever arrive, otherwise I will make brake hubs for the wheels I already have. For grass I do not think it will need brakes.The wheels I have are quite thin and fit the wells easily, only problem is they have nylon hubs and the tires are foam filled with a rubber skin. Have you balanced & weighed yours yet ?.

Dave

[David Brown]

Hi Graham, took a look at your build and its all looking good. I see you have gone for the wren 75 in the end, that should be well powered. What colour scheme are you going for ?. You say you are looking at around 6 kg ready to fly, I thought that with ours but the ballast killed it and we put everything including the kitchen sink up front, ours are 23lb ready to test fly with the bubble trap full & about 1/2 pint of fuel in the tanks.

Dave

[graham trever]

Hi David

I have done it in a plain silver finish for now while I get it tested.I will now fit it out and do a balance and weight. Tony N did not have brakes ,he just tightened up the free wheeling effect of his wheels.I was at wren last week and the wren jubilee is to become the jubilee 80 as it has 8kg thrust so I think I have plenty in reserve.I think I would prefer having brakes but will look into that when I refit all parts again for final fix.Will put some more picies on forum when I get it put together.Lets hope there is enough lead supplies in the county for a balance.I will keep you posted.

best Regards

Graham

[Vince Raia]

Hi Guys, little tip that may be of use to you, instead of putting lead in the front, use batteries which can power your lights, if you are putting them on, you can also get different sized gel-cell which are a good source of weight, then you are making use of the dead weight.

HTH, Vince.

[David Brown]

I agree but lead fits where batteries do not. with the vamp the nose is so small you can't get any batteries up there and as all us men know inches count . being serious I have 2 batteries as far forward as they can go and pump and valves and still the beast needs ballast, its down to turbine location against fuel cell location. Tony has chosen the tanks on the c of g where as Kerry chose a compromise with the tanks in front of the c of g. I have built both but as yet not flown Tony's. Kerry's needed trim adjustment as the fuel burnt off, Tony's should not need this, I test run the turbine in the air frame again today readying for a test flight as soon as the weather / strip allows me.

Dave

[graham trever]

Hello David

Added some photos to forum after fitting U/C.Did a quick weight and with 3.5 lbs to balance on wheels ready for all other bits it was showing about 15lbs.Just weighed turbine with all it bits and 3 packs of batteries 4.5lbs.I think it will be inside of 20lbs so should be ok.Will let you know when all fitted.Hope you have tested yours soon so I can have a report.

Regards

Graham

[David Brown]

Hi Graham, can't get onto your site, struggled last time but no go now. keeps coming up as downloads then nothing. Can you post them on here.

Dave

[graham trever]

Vampire 047.JPG (122.42 KiB) Viewed 15908 times

Hello david

Just going add a couple of the latest Photos as it get ready for fitting out and more testing.

[David Brown]

Thanks Graham, gives me a boost to get mine flown. Looking great, keep up the good work.

Dave

[Tony Nijhuis 2280]

Hi Dave and all,

Good to know the models are nearing completion and great to see your getting under the target weight too. Just a reminder that the C of G is critical on this type of model as the booms provide very little in the form pitch stability, so please make sure you are on it or better still (for the test flight) just in front of the stated Cof G. It will need nose weight so please don't skimp on this.
I mention this because when testing mine with Colin Hammond, we tried moving the balance point back to save on ballast.....she got very twitchy and we nearly lost her. Needless to say we added it all back and she back to being an absolute peach to fly...... Even managed a tail slide when my stall turn went wrong

[graham trever]

Hello All

This is the youtube link to a quick startup and I hope to make test flights this coming weekend at Winterton if the weather is right.The balance point is right on with no fuel so should be ok. Finishing will take place later. Weight with ballast and no fuel was about 22Lbs.

http://www.youtube.com/watch?v=BD6dS_zw ... TQ&index=1

Cheers

Graham Trever 4875

[David Brown]

Looks and sounds the part, I see you have the tank well forward. Ours are almost ready to go, just need some decent weather to give us the enthusiasm to finish them. Good luck with the test flight.

dave

[David Brown]

Hi Graham, did you manage to test fly yet. Mine is still as before but will be taking to the Wren open day on Sunday for static display, John has made a casting for nose weight to fit in the cowl of ours 1.5lb in weight.

Dave

[graham trever]

Hi Dave
The sad news is that on the test flight which was going well when it suddenly took a right turn and dive which I seemed to have no control of.It just spiraled into the ground and was no more.I managed to shut engine down and there was no fire but one big pile of bits.On inspection all servos but one still good, but the one was one half of the elevator and it was seized solid.It must seized during flight and when it hit it bent the control horn.All moving surfaces were still hinged and in working order apart from that half of the elevator.Turbine has some dents on it but is spinning ok.Will have to send back to wren when I am ready. I did want to go to Sundays open day but prior arrangements got in the way.A bit of a loss at the moment but just serviced the boomerang and maule for next weekend so onward and up we go.

Best Regards

Graham