Noun
an artificial cloud created by an aircraft; caused either by condensation due to the reduction in air pressure above the wing surface or by water vapor in the engine exhaust
Source: WordNetThree aircraft—a DLR Dassault Falcon 20, NRCC Canadair CT-133, and NASA Dassault HU-25C (Falcon 20G)—trailed the DC-8 that was using a 50/50 biofuel blend, collecting ice particles and monitoring contrail formation. Source: Internet
It used 6 x 40960 NS O Contrail Rockets motors giving a maximum thrust of 8 metric tons. Source: Internet
All I am saying is two aircraft flying beside each other, and one has a contrail, and the other does not. Source: Internet