Originally Posted by ysolomon
jofro or anyone, how do you translate KW into lb of thrust? Is there a general rule of thumb? What other factors are you taking into consideration?
I was not aware that this model is 40lb... I'm a bit concerned too... At the same time, I will be flying an 18lb F-18 on a 4000W Dynamax fan, so my ratio is only slightly better.
To your first question, I don't think there is a rule you could translate. That's why you have efficient and lot of non-efficient EDF systems. I always upgrade my EDF models to give me aprx. 900-1100grams of thrust (2-2.5lb) per Kwatt. Your "F-18" figures don't look very good to me at 220w/lb. as most of my 90mm EDFs around 10lb AUW push over 4Kwatts. It's always good to have few spare bucks in your pocket, but then again there are some people who enjoy flying 'bricks' or cement blocks.
I only wish best of luck to "Falcon" with his model, that I find very in-efficient with the figures he showed so far. I would still like to know how much it actually pulls statically on the ground while being hooked to the digital scale. I'm aware it could fly nicely at 130m/h but you have to reach that speed first, Joe.