Redline7000

My Feedback: (2)

What's a good power / weight ratio for turbine models?

KC36330

depends on the model in question.

pilott28

My Feedback: (27)

I agree with KC. What a lot of guys do is post the specific plane and engine combo here they are considering and look for practical feedback. The manufacturer of the kit should also tell you what makes sense.

A couple of other thoughts, though ....

Don't always beleive the weight figures quoted on kits. Get some real world data, or wait to make an engine decision until you have the kit, have weighed all the parts, and have a pretty good idea yourself.

Personally, I try to keep most kits in the range of .85-1 to 1. In practical terms across a large range of kits, this has always worked well for me. The lower you go, the more throttle range you will give up and the less power you will have if you get yourself into trouble.

If you are someone who loves speed and the kit is engineered well enough to handle it, 1+ to 1 works too.

jclittle

My Feedback: (99)

The others nailed it, it all depends on what model. My Kingcat has 36 pounds of thrust and weighs 28 pounds empty, while my MB339 weighs 39 pounds empty and has only 30 pounds of thrust. Yes the KC is faster (much ) then the MB but the MB still flies very nice with only 30. Check the mfgs specs - I would personally lean more towards the high end and dial it down then not have enough thrust.

Redline7000

My Feedback: (2)

The project I have in mind is a 4M sailplane. Either a Salto or a Lunak. Flying weight as a glider for both models is 12 Lbs. Empty weight is 9 Lbs. Both have wing areas exceeding 1000 square inches. With a Wren 44, fuel and all other ancillaries I estimate the flying weight at around 13 + Lbs. Will the 44 provide enough thrust? I"m not looking for speed, just some awesome fun. Since this is dark territory for me, anybody want to contribute with their knowledge? Thanks in advance.

KC36330

a 44 would be more then enough. fuel load on a sail plane is only intended for minimal engine on time, not sure if you took that into consideration when you figured the fuel capacity or not, the 44 is very economical on fuel.

Redline7000

My Feedback: (2)

I considered a 32 oz. fuel tank plus a UAT. I intend flying it as power sailplane ... maybe I'll slope it one day! LOL!

erbroens

I would guess that the 44 will be close to ideal, as there is a full sized glider flying with twin 45 lbs powered AMT´s!

The Salto with the V-tail and acrobatic capabilities is a fine choice for this project, IMO.



Saludos, Enrique

KC36330

i think you'll be right surprised at how often you're at idle while in flight and how long of a flight you can get with that quantity of fuel, sounds like a fun project, good luck with it and keep us posted.