Abstract |
The study was primarily of an experimental nature directed at observing and evaluating the results of applying existing automotive emission control techniques to aircraft piston engines. Attention was restricted to the emissions of unburned hydrocarbons, carbon monoxide, and oxides of nitrogen. Control techniques considered were those primarily used to reduce hydrocarbons and carbon monoxide, since the rich mixtures normally used in aircraft operation inherently lead to low levels of oxides of nitrogen. The general program approach was to select two typical engine configurations, design and implement selected emission control provisions, establish baseline emissions outputs for the standard engines, and determine the effect of the various emission control techniques and systems relative to the baseline values. A Continental 0-200 carbureted engine and a Lycoming IO-540 fuel-injection engine were selected for evaluation. The report describes the control approaches selected and tests conducted. Results are presented and discussed. Pertinent data are included for reference. (Modified author abstract) |