Why two stroke engine not used in aircrafts?

In the two stroke petrol engine as you know suction,compression,ignition,expansion and exhaust is completed in only two stroke and one revolution of crank wheel

more over diesel ignites at very high pressure which is not the same in case of petrol........if petrol is also ignited under pressure it explodes producing a big thumping sound.called KNOCKINGthis may reduce the power output and also lead to breakdown of the engine.

For the above reason two stroke engine cannot compress air and ignite the fuel like diesel engine.