Yes - I was going to ask the same question as Xair - what are to going to put it in?

I guess there's two main things to consider right up front:

1 - the weight of the aircraft you are trying to push. An all-up Weight/Thrust ratio of 1:1 is more than plenty of power for some flyers. e.g. A 10kg aircraft (including the weight of the Turbine + Fuel etc) should fly ok on a 10kg Thrust Turbine.

2 - what dimensions do you need to work within? There's a fair bit of physical size difference between an 1800 and a 3000. Go to the JetJoe site and check the total length, diameter and weight of the various thrust Turbines and maybe work backwards from there.

And don't forget, a JJ3000 producing 13+ kg of thrust is going to drink fuel like a fish when comapred to a 8kg thrust JJ1800. So you would need to decide on what sort of flying time you are looking for and then work out what amount of fuel you'll need to achieve that time. If you use 0.8 kg/litre of fuel, you won't be too far out. For example, a JJ3000 drinks about 16oz of fuel per minute on full noise. Thats about 473ml per minute. Call it 500ml = 1/2 litre of fuel per minute. A 5 minute flight would therefore require somewhere around 2 1/2 litres of fuel - make sure you calclulate enough left over to land with, or you'll be dead-sticking it in all the time LoL And don't cut the calculation too fine - you might need to abort a landing and go around again - you'll need fuel for that. Better to land with left over fuel rather than crash due to no fuel...

Continuing with this example, apart from 2 1/2 litres of fuel adding around 2 kilograms of weight at take off, you also need somewhere to put it. Try to visualize what amount of space 2 x 1lt coke bottles will take up in your airframe.

A JJ1800, on the other hand only consumes around 9oz of fuel per minute - roughly half the power for half the fuel consumption.

What kind of craft are you looking at powering?

BJ