Hello,

Her is the spec of my next jet, what do you think about it (weight, length, wingspan ratio, etc.):

Length: 48 inches
Wingspan: 46 inches
Weight: 12 lbs (estimated)
Wing area: 550 square inches (approx)
Engine: JetCentral Rabbit (19 lbs)
Tank: 50oz

It’s a design base on the F22, it’s not a scale to minimize the complexity and the weight… It’s will be equipped with flap, retract and air brake…

Thanks for your comments.

Robin

The Rabbit seems like a lot of power for such a small light weight plane; but hey that's why there is a left stick

I known... :-) But I'm more concerned by the fact that the wing area seem to be small (in comparison with normal airplane (like Extra 300)), but as it is a jet, it might be normal, that what I don't know...

Also, the jet is design to be able to get very hi speed, so that's the reason of the little "overpowered" engine... But, having a little plane, also mean a little wing to support the same weight...

Any comments will be more then welcome... again : thanks...

Robin

That's 50 oz/sq ft. on a 46" wing span. Assuming that's the dry weight, that's about 15 lbs wet which is 63 oz/sq ft. - even worse. I would think that this jet is going to be a real handful. I would not get the wing loading up that high on that small a wing if I could help it - especially since it appears its going to be a self-design. In addition, as stated, the Rabbit is too much engine for that plane and I'd be surprised if you can actually bring it in a 12 lbs (dry). I would not want to risk a brand-new Rabbit test flying this airplane...

Yes, there are lots of jets out there that have a higher wing loading, but generally they are much bigger and bigger flys better at heavier weights (Reynolds numbers).

Bob

Hi Robin ,

You say this will be your next jet . What jet experience do you have ? What kind of airstrip will you be flying off of ? You'll be hard pressed to make a 12 lb airframe with an engine the size of the Rabbit and have all the goodies that you mentioned . Also 50 oz of fuel isn't going to be enough for the engine unless you only want 4 min flights . Just a few more things we need to know about your plans before we can give much useful advise.

Marc

Great, that the kind of posts I want ! ;-). Ok, how much wing area you think might be good ? (same engine, same weight)

And yes, it might be around 15 lbs wet (but still, the plan is under design, so things may change, that why I'm asking questions and ask the experts you are...)

Thanks,
Robin

Mark, Actually there is no completed plans (as I looking for safe value to design it), I never did any jet, but did over 10 aircrafts since the last 15 years, mostly aerobatic kind (extra300, cap231 style, etc.) mostly all of them flew well (except a biplane which was a disaster...;-))... But jet is a very new world for me, and before doing or buying anything I'm asking question...

It is not excluded that I also buy a first jet (let say ARF) in the process... But anyway, those questions remain and your help and expertise is very appreciated...

Robin

I'm going to fly mainly on grass "runway", and most of the paved runway I will use have grass strip were I will be able to land on...

Robin

Robin, if your going for your first jet then I would suggest a Boomerang (Sprint/Baby or Elan) or Reaction 54 or something along those lines.

Thanks everyone, I will go back and redo my homework, And yes I may go and buy a trainer jet first... I will keep you in the loop....

Again : Thanks to eveyone, you help and your expertise is amazing... ;-)

Robin