This should really be looked at by those producing Diesel engines for Airplanes.
The biggest problem tinker's face when trying to put a Diesel engine on an airplane is that the Diesel has very massive "power surges" each time a cylinder fires, and a nasty power "stall" when it's compressing a cylinder. This isn't a huge deal with the other applications of Diesel engines, they just add mass to the fly-wheel and transmission and that takes care of it. In Airplanes however, the mass costs too much (in terms of airplane weight) so they try to reduce it as much as possible, however if you reduce it too much the propeller is literally torn apart by the surges and stalls. Early tests had the propeller lasting only hours when running on a 4 or 6 cylinder diesel. If there is a reduction drive on it to bring the RPMs further down they too like to self destruct with a Diesel.
If they could use a low-weight magnetic coupler to absorb the surges and stalls and provide smooth power that would solve the biggest problem putting a diesel on an airplane and would really boost that market!