Letters: 06/04

Cheap Heat
Living in Wisconsin, those of us with unheated hangars (or no hangars at all) can certainly appreciate the need for a cabin heater as we’ll as one that pre-heats the engine.

What a number of aircraft owners and I have used are the ceramic cube heaters which are widely available for considerably less than the $475 Tanis system you reviewed in the May, 2004 issue. They have adjustable temperature settings and automatic shutoff in the unlikely event that one gets tipped over.

I place mine on the floor behind the co-pilots seat pointing toward the open floor on the left side of the airplane so the hot air doesnt come into direct contact with the upholstery. Ive never had a problem with mine and the entire cabin, including all of the avionics, are nice and warm after a few hours at less than the maximum temperature setting.

I don’t see the sense of spending that kind of money when a suitable substitute already exists for a lot less.

-Bob Bernstein
Oshkosh, Wisconsin


Turbo Feedback
I have some feedback for you on the turbo article in your April, 2004 issue. I have flown a 33 Beech for about 7000 hours and added the turbo conversion in about 1985. Initially, I was not happy with the results.

Low-altitude performance was degraded significantly, there was also increased maintenance and component failure. I also continued to have the normal mid-time top overhaul requirement that I had experienced with the normally aspirated IO-520.

Over the years, a number of components were upgraded and improved baffling was added. There was some performance improvement as a result. I had my last IO-520 blueprinted and some additional upgrades to the turbo system were installed and finally, the turbo seemed worthwhile.

I had experimented with lean of peak operation, but was unhappy with the loss of performance running 25 inches squared.

At about 700 hours on the engine, the oil consumption was getting to be what I thought was too high, so I called the engine rebuilder. He suggested a change to a different oil.

He also asked whether I ran lean of peak and I after I told him about my concerns about less power LOP, he talked about the wide open throttle (WOT), high power setting. When I gave it a try, there were three results–power management became easier, I flew faster on less gas and oil consumption stopped.

I flew that engine for about 2100 hours of which 1400 hours were at WOT and LOP between 83 and 90 percent power. CHTs typically run 290 to 325 degrees F. When the engine was torn down-still running good with high compression-I was told it looked great inside and whatever I had been doing on that engine, I should do on the next.

I switched to an IO-550 and am at mid-time on the engine. It doesnt use oil and still has good compression. I true 190 knots at 9000 feet and because of the increased climb rate with the IO-550, its easy to operate in the mid teens, even for short trips.

I made a recent trip to Fort Myers from Chicago in four hours door to door, which is fun, but the real advantage of the extra speed is into the teeth of a big head wind. I rarely see less than 150 knots groundspeed and that will beat the airlines today on a pretty long flight.

My experience says that the engine will run longer WOT and LOP with less maintenance required. Im sorry I didnt start a few engines sooner.

-Nick Wilson
Via e-mail


Hangar Paint
I read your January, 2004 article on painting hangar floors with interest. I need to decide what paint to use on my hangar floor (new concrete) and am wondering if you could give me a quick, preliminary report on how your various types of paint are performing so far.

Ive used three different types of paint in different garages in three states–two-part epoxy in Minnesota, water-based latex in California (emissions controls) and Sears oil-based enamel in Texas.

I had the best luck with the Sears floor paint; it was the easiest to apply and relatively inexpensive, but they don’t sell that type any more.

I want the epoxy results but if it doesnt perform well, Id rather repaint with a single-part paint more frequently than go through the effort of horsing around with epoxy. Any advice?

-Bob Falstad
Via e-mail

Yes. Horse around with the epoxy and get the best quality product you can afford.

The inexpensive Rustoleum product we bought from Home Depot is already lifting but the expensive epoxy from Griots Garage looks terrific. Its also more resistant to dings and scuffing.


Headset Volume
In your review of high-end headsets in the May, 2004 issue, you failed to mention one problem with the revised Bose X. The volume controls have no click stops. They move with the lightest of touches.

A more general question for the headset manufacturers is why no one can make a unit with volume and balance rather than dual volume controls. If they must do dual volume controls, then give me markings so I can keep the settings the same.

-Paul Platt
Via e-mail


Gas Guzzlers
Reference your article in the March, 2004 on gas guzzlers: are you being objective? You have a variety of apples and oranges in the table (see page 22) that can be more effectively and more correctly sorted than shown. Allow me some observations.

Speed and fuel burn are only part of the relationship that needs to be used for comparison purposes. Useful load is also important. For instance, the POH for my Cessna 182RG indicates these numbers: 145 knots TAS at full gross while burning 11.7 GPH at 6000 feet on a standard day. The useful load is 1230.7 pounds.

But how should these figures be combined to be objective when comparing my aircraft to another, or even to compare it with the Escalade?

Surely the correct way to do it is to multiply the useful load by the speed and divide the product by the fuel burn per hour. The answer can be expressed in pound-miles per gallon-Ill call it the efficiency number-and my 182RG comes in at 15,247.

If it is assumed that the Escalade can carry a cabin and fuel load of 1750 pounds while burning 5.3 GPH at a speed of 54 knots (your table), then it carries an efficiency number of 17830.

So the Escalade is a more efficient hauler when carrying capacity, speed and fuel burn are considered. Clearly, some aircraft are meant to be heavy haulers while others are designed to be speed demons. Is it not correct to observe that one cannot get both speed and a heavy hauling capability for the same fuel burn unless, by virtue of more impressive airframe and engine efficiencies, the heavy haulers speed is made equal to the demons speed?

Clearly, the heavy hauler will have a higher efficiency number in this case. As well, one could choose two aircraft which have equal useful loads and speeds and the fuel burn will tell you which is the most efficient in getting through the air.

Finally, to be fair, one should divide the efficiency number by the dollar value of the aircraft to see which aircraft gives the best efficiency per dollar invested. But speed has a value if crewing costs are included and, of course, time is money unless one flies for the sheer joy of it.

Given the above observations, not only can the apples be separated from the oranges but the size of each begins to emerge. And it is unlikely that the Cadillac Escalade would be at the bottom of a list using the comparison basis presented here.

Might it be the only apple in the list? Enough said, your ball.

-H. Glen Gilchrist
Calgary, Alberta

You don’t, perchance, work for General Motors, do you? We used the Escalade simply because it has the worst mileage of any popular SUV we could find and the truth is, most of them drive around with one person in the vehicle and rarely haul anything approaching maximum capacity. The same can be said of many airplanes, although some owners do need hauling capability. Your comparison is certainly valid as a means of comparing efficiency versus load carrying capacity. We used the simpleton approach merely because of limited space on the pages. we’ll look into efficiency and load carrying in a future issue.