what would be better for about 1kg rc plane(mk2 design),i have two options ie.nitro engine-os15la (2.5cc)or diesel engine 3.2 cc.please provide some advice,i need it urgent to decide as i hv to perform in iit kanpur

Both will be ok - depends upon your requirement

for duration and "mileage" - diesel - (more vibrations)

for pickup and speed - glow


the above is an over simplification - but should help you decide.

Well... for Glow OS 15LA you may substitute it with a Sharma 2.5 CC diesel. Bot remember one thing.. if you are a novice getting to master a glow for starting and tuning is a wee bit easier than the diesel one..... because on the glow one just has to adjust the fuel flow needle and use a starter to start it.  For a diesel... the fuel flow needle and the compression ratio beth need to be adjusted correctly and that takes a wee bit more of practice... BUT BOTH CAN BE MANAGES WITHOUT PROBLEMS.