its an electric engine. I use to work on rc planes and cars, trust me if it was nitro you would know it.
and its just a recorded sound track played from the nose cone, connected somewhere between the motor and receiver.
and that plane is waaay to nose heavy.
if you're saying that from thew taxi or from the landing, every mustang i've seen taxis like that on grass, including mine, and mine is not nose heavy.
as for the landing, it seemed there was a crosswind, and he just got caught up in correcting for that, and forgot to flare.....twice.