by Pete Schoeninger
Published in Midwest Flyer – February/March 2017 issue
Q: Pete, I saw a picture of an Ercoupe on skis. I have NEVER seen an Ercoupe on skis, so are skis approved for Ercoupes?
A: If you do an Internet search for Ercoupe type certificate data sheets, you will see that skis (Federal 1500) are allowed on Ercoupe model 415C. But interestingly, skis were not approved on the heavier 415D model at the time of certification.
There are many airplanes flying on skis where ski installation was not approved by the airframe company and the FAA. In this case, usually the ski manufacturer will obtain a Supplemental Type Certificate (STC) from the FAA, granting authority to install a particular make and model ski. Or in some cases (Cessna 170, for instance), the manufacturer will certify one make and model of ski when the airplane is certified. Later, ski manufacturers can (and have gotten) their skis approved.
Q: Have you ever landed on a frozen lake with skis or wheels? What should I know before I try it?
A: Yes, both. Be very careful. Check with some local pilots if at all possible and be very careful and walk the area you plan on landing on to look for hazards. Check with local pilots, ice fishermen, conservation wardens, snowmobilers, etc., who can warn you about springs or currents which may be hidden beneath very thin ice. Look on Facebook for “Midwest skiplanes,” and talk to them and go to one of their gatherings. And if you do venture out, be sure to have a life preserver onboard, if not wearing one, and hone up on some emergency egress procedures, so you can quickly get out of your aircraft and out of the cold water should you break through the ice. It is just a matter of minutes before hypothermia can incapacitate you.
Q: In my Cessna 210, when I make my first power reduction from take-off to climb, the cylinder head temperature (CHT) and oil temperature gauges will reduce a little. But the exhaust gas temperature (EGT) gauge does not drop. Why?
A: There is not enough room to explain all of the ramifications, so you should spend some time with your engine owner’s manual. In a nutshell, at takeoff power, you are running full power and full rich. At first power reduction to climb power, you lean fuel flow a little with your fuel flow gauge. Reducing power and leaning mixture (from very rich, to rich) just a little changes exhaust volume, but maybe not exhaust gas temperature. This situation will vary with makes and models of engines and airframe installations.
Q: The engine in my 1978 Cessna 172 (Lycoming 0-320 H2AD) holds 6 quarts of oil. The engine owner’s manual specifically states that the minimum safe oil quantity is 2 quarts. But my mechanic and CFI tell me I should always have at least 5 quarts in the engine. Oil is not cheap…why carry more than necessary?
A: I agree with your mechanic and CFI for many reasons. Some conclude, if for some reason you develop a small oil leak, you can run for awhile before running out of oil, and hopefully get to an airport or at least a suitable emergency landing place. Engine oil helps remove engine heat, and more oil means oil can cool a little more before it is recycled thru the engine, again meaning lower oil temperatures.
Q: I have noticed that rural airport ramps and runways seem to have more snow and ice, and it seems to stay longer than on nearby streets. Why?
A: Three reasons: 1) Sometimes corrosive materials, like rock salt, are used heavily on roads to melt snow and ice, but are NOT used on runways because salt corrodes aluminum. 2) Almost any road has lots more car traffic (which compresses and melts snow and ice) than airplane traffic on a runway or ramp. 3) Relatively few voters use the airport, but everyone uses local roads, so there may be more political pressure to do a real good job on roads before airport plowing gets underway.
Q: I have been considering upgrading my Cessna 182 from a carbureted engine to a fuel-injected engine, but wonder if the cost of converting is worth it.
A: It all depends on how long you plan to keep your aircraft, and if you will be flying at airports with higher elevations than we typically see in the Midwest. There’s no question that a fuel-injected engine is the better of the two engines. With no carburetor, you don’t have to worry about carburetor ice. Fuel is also distributed more evenly among all cylinders, so the cylinder temperatures tend to be more even, and as a result, the cylinders tend to have a longer lifespan. The drawbacks, besides the cost of converting, is that fuel injected engines tend to start harder when the engine is hot – at least until the owner learns how.
Q: Automobile dealers frequently buy and sell cars at regularly scheduled auctions. Is there such a thing for airplanes?
A: The only regularly scheduled airplane auction I am aware of was in Cape Girardeau, Mo., and that ended about 30 years ago. It was useful for dealers and FBOs who maybe took something in trade or for an individual who wanted to “dump” their airplane at wholesale for a quick sale.
Q: As a follow up to my question about auto dealers, how can I buy a couple of airplanes at wholesale? I am an A&P mechanic with Inspector Authorization and can do all of my own work?
A: You should let everybody in a 400-mile radius or so know that you are a wholesale buyer. But what that means is you must have cash or a line of credit ready to go on a day or two notice, and be willing to buy almost any brand/model, and in any condition. If FBOs or dealers call you a couple of times to make an offer on a trade in and you decline, they will stop calling you. When Jeff Baum and I were buying at wholesale (as we started Wisconsin Aviation 30-plus years ago), we bought Cessnas, Pipers, Beechs, Grummans, Aeroncas and Cubs, and some aircraft you have never heard of, in almost any condition. Some were real beaters and some were nice. And I have to admit that occasionally, we lost a few bucks doing it. But overall, it was a lot of fun, and we did alright.
Q: As a follow up to my question about selling my 182 and buying a 310, which you answered so brilliantly in the Dec/Jan 2017 issue of Midwest Flyer Magazine, I have found some 182s similar to mine advertised in the range of $50,000 to $60,000. I am going to start advertising mine at $62,500, unless you have a better idea?
A: If you price your 182 at the top of the heap of similar airplanes, there is little chance it will sell. Then after 45 days or so, it will become kind of “stale” on the market and to sell it, you will have to lower your price below the middle of the market to attract a buyer’s attention. I would start advertising it in the middle of the pack or so, say $55,000, and see what happens.
Q: I saw a 172 with a bit of duct tape over part of the front cowl openings. The owner says he does it every winter so the engine runs a little warmer. Would that be a good idea?
A: NO, NO, NO! Cessna, and other manufacturers, make and offer for sale airflow restrictors called “winter fronts.” They are carefully engineered to allow airflow throughout the engine, but at a slightly less volume. With “homemade” winter baffles, you could be creating hot spots on the engine, besides probably being illegal.
EDITOR’S NOTE: Contact Pete Schoeninger at firstname.lastname@example.org with your questions for this column or for consultation on aviation business and airport matters. Pete has four decades of experience as a line technician, airplane salesman (300 aircraft sold thus far), appraiser, snow removal supervisor, airport manager, and as the manager/co-owner of a fixed base operation.