Reduction of Jet Engine Exhaust Smoke with Fuel Additives

An investigation of fuel additives was conducted to identify materials which will reduce or eliminate jet engine exhaust smoke. Many materials were evaluated in a full-scale combustor rig, and the better ones were further tested in full-scale engines, both on the ground and in flight.

Several additives were found capable of essentially eliminating smoke under some conditions. Although all of them formed solid exhaust products, in some cases these products caused no major adverse effects on J79 engine operation in limited endurance tests.