The bad news: There really isn’t much you can do to run an engine much more frugally than you do during the normal course of operation.
The good news: There are a few things you can do to keep operating costs down.
I’ve always been a big believer in operating the engine at best power rather than best economy – and I don’t intend to open the Pandora’s Box of running on the lean side of peak EGT, either. However, in an effort possibly to reduce fuel consumption, operating at best economy may be one way of conserving cash.
Before jumping right in and doing that, I’d encourage you to review your Operators Manual, Pilots Operating Handbook or Aircraft Flight Manual. Another great source is Lycoming Service Instruction 1094D.
You may operate at peak EGT, but please use common sense and please realize that all leaning recommendations are based on calibrated instrumentation.
If you haven’t had your gauges calibrated within the last couple of years, then don’t risk trying to operate the engine at a leaner power setting. We all know that engine temperatures may increase slightly, so we want to be confident that our EGT, CHT and oil temperature gauges are feeding us accurate information so, if need be, we can adjust our power settings. It’s absolutely essential that we keep the engine operating temperatures within the manufacturer’s specifications.
Just as a rule of thumb, you should remember that, to achieve maximum service life from your engine, it’s recommended that you keep the power setting at 65% of rated power or less (except on engines that have yet to be broken in and oil consumption has stabilized). Cylinder head temperatures should be at 400°F or below, while oil temperature should be from 180° to 220°F.
Something else to check is the carburetor heat door on the air box. Make certain it is functioning properly. If it’s not working as it should, it may be allowing hot air to pass, which enriches the mixture, resulting in higher fuel consumption. That is something that can be checked quickly by your maintenance personnel.
Another easy thing to do is have your spark plugs checked and cleaned. Also, check that they are properly gapped for best performance. If you intend to operate at a lower power setting than you have in the past, ask your maintenance technician whether going to a hotter spark plug would benefit better performance for your type of operation.
I’m sure there are other things you can do to fly frugally, but I’ll repeat what I said earlier: Please use common sense when making any adjustments to your operating procedures. Assuming you’ve gotten good service from your powerplant in the past, don’t get too carried away trying to save big dollars by making radical changes, because it could end up costing you more in the long run.
Paul McBride, recognized worldwide as an expert on engines, retired after almost 40 years with Lycoming. Send your questions to: [email protected].
