Cactus999
Posts: 16
Joined: 8/5/2003
From: Vilnius,
Status: offline
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Once i was thinking about using arine engine. thing is, that most marine engines are heavier than aircraft ones, mostly becouse worse situation with cooling. Altho water cooled head works efectively, but whole engine cranccase must be heavier, to withstand thermal shocks at hi rpm. So thats heavier engine part. Next goes cooling system. youll probably need quite big surface radiator (much bigger than surface of regular air engine, due to indirect cooling). next isue coolant pump, tank, batery. I beleive this will ad aditional few pounds, to few pounds of gearbox, cardan shaft etc. Its not that dificult to cool engine inside enclosed fuse. With help of simple duct made from cardboard or balsa, you can guide loads of air thru fins with help of fan, whitch can be belt, or direct driven with engine itself. Electric cooler seems more realible, as wont face probs when taxing, but its failure will mean that engine will oveheat, so i would go fan driven from engine, as most early hellis had, and such as now used on some rc cars.
I think ist not worth to play with water cooling, as more critical parts ur system includes, more chances something fails. Theres some plans avialible with planes that have engines inside fuses (pusher planes). I think you might suceed instaling engine in center fuse, but this will make you put all hte rest stuff in nose to keep plane light. TF aircobra is just bit to small to fit more advanced things like liwquid cooling, gearboxes etc. It would make it either too complex, either too unrialible, and in any case very heavy.
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All Forums >> RC Airplanes >> RC Warbirds and Warplanes >> "Mid-Engine" P39 
"Mid-Engine" P39 - 
there's the universal joint to go between motor (or engine) and the shaft... a brass bearing tube and the threads on the shaft (and a hole for a stop pin) al pre-done for you. 
