Budget EDF jets for 2016

Started by deltawing, January 18, 2016, 01:01:15 PM

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RogMason

Yes, a very low pass!! 
Did you notice white vapour during the roll(s)?  Don't know what that is?
'Roger That...'

deltawing

If the white vapor is behind the wing tips, it should be the moisture caused by high pressure vortex. Usually it happens and visible on sharp turns like a roll.

RogMason

It appeared to me to be coming from the engine tailpipe during the roll? It happened 3-4 times in the video. See attached captures.

BTW, I agree with you - 15-20 feet on the low pass!! Yikes!
'Roger That...'

deltawing

Those are contails (condensation tails) from hot jet engines.
Carbon dioxides, unburned fuel, all sort of fuel components etc and hot humid vapor came out from jet exhausts around the cold surrounding causing quick condensation and forming cloud like white tails.

Similar to white smoke from car exhausts in winter.
For jets usually only be seen up high as temperature is cold there.



Wingnutz

Philip,
Really enjoyed the videos of the full size and yours and Loi's Durafly Vampires! Thanks for posting!
I'm fascinated by the launch dolly. How do you ensure the model stays on long enough to pick up flying speed and then separates from the dolly?
All three runways at my local field are grass and the small wheels on my Durafly Vampire make take-offs cardiac events! Have set up the Vamp for bungee launch (yet to test) but your launch dolly is a really interesting alternative!
Bobcaygeon Bill
DOWN WITH GRAVITY! UP WITH LEVITY!

deltawing

Hi Bill,
In fact I never thought about that. Since the jet is just sitting on the dolly and the front part is higher than the back by design, as long as the air speed get enough lift it will starts moving faster and separate from the dolly.

This dolly idea is from Loi, his initial design was four wheels, because of much play on wheels & shaft it never go straight on run way.  I advised him to remove the two back wheels and add a third wheels as far as he could. That is how this tri-wheels dolly come up.  The key is the third wheels has to be far enough to go straight.

If your field is all grass, suggest using 'BIG' wheels to get around. the dimension of the dolly is not critical, mine is 12"x11.5", Loi is smaller.   My front support is 1" higher than the back support that the jet sit on. I just hand cut a curve as support surface, Loi use 4 support points.

If your aim is for Vampire, sure it will works on most designs as it needs little air speed to lift up.

By the way I used my bungee launch on the Vampire for others, IMO this dolly is easier.

deltawing

If you are wondering how the BAE hawk flying, one mentioned here, here's my latest T-45 video at Rogo.
It is another floater like the Vampire, even more durable/repairable. If you see mine closely you'll see all the ugly repairs.  ;D

https://youtu.be/Kk-gPh5kIkk


deltawing