I have a twin engine Bronco that shows a flying weight of 4.4. lbs. without fuel or engines. It calls for .15 engines but I have two .25 engines --question is do you think that will be alright to use versus the .15's??
.15 sounded small to me so I did a quick look for a general thrust of a .15 motor. I saw that a .15 is about 804g (1.77 lbs) thrust with an 8.4 prop. By those numbers I think that would be a struggle getting a 4.4lb plane off the ground. But this is not my expertise. Need actual thrust tests of your motors vs the wing loading and all that stuff that requires maths to understand.
I am sure others can point you at actual numbers you need to know for sure.
Thanks for the info- I think I can fly it- not real good but not a beginner and I thought the .15 seemed a bit small plus I only have 1 .15 but 2 .25’s I will try to post before and after flight pics.....landed plane or rubble lol
id say that actually it doesn't matter what your engine type is unless your worried about the weight or flight time of your aircraft. just remember if its sensitive decrease the throttle and stay calm!!!