Big difference if you are doing low-altitude agricultural work vs. long-range stratospheric flight.
No. 2 Diesel is used in ag operations.
The biggest difference isn't in the fuel purity, but in the fuel control setting. It's a simple adjustment in most cases.
As for upper atmospheric work, the USAF has been doing long range research and work using biodiesel. You're not going to toast an engine.
Additives can be provided for lower temperature use, and there's always fuel heat.
It's that I was watching Apocalipse Now last night and they put diesel fuel
from a boat in a UH-1 helicopter and I didn't know if that can be done.
You bet it can be done. If it's a military craft, chances are that it's already using JP-4.
Corrective action was to completely drain and refuel with JP-4-- so it appears that the engines don't really see much difference.
JP-4 is a cut fuel; kerosine and gasoline, and the approximate equivalent of civil Jet B. One of it's chief advantages is a low freezing point.