Letters 04/98

Three-Blade Props
Your article about three-blade props caught my eye right off. I have owned three Cessna 180s and have about 2500 hours in them. On the 1974 model I currently own (picture enclosed), I have recently done certain modifications including a three-blade prop that increased the speed in a significant way.

First, it has been my experience that most Cessna 180s are good for about 150 MPH at cruise and it doesnt make much difference up to about 7000 feet. Above that altitude, they lose speed and show reduced indicated air speed.

Indicated air speed on a standard 180 will be in the low 140 MPH. Above 6000 feet, this will fall to about 135 MPH at 9000 feet. You can figure on 130 knots average.

I have three modifications to my 180 that increased the cruise to 150 knots. The first was the Snyder speed kit, which faired the gear and gear legs to the wheel pants and added a fairing to the horizontal stab. This increased speed by about 9 to 10 knots.

I then installed a low-compression O-520 carbureted engine that replaced the stock O-470. Along with that, and part of the STC, was a three-blade 881 McCauley, which they dub the Big Foot. This replaced a two-blade 8811 McCauley.

This increased speed by 10 knots or a total of 20 knots. Now the indicated air speed is just slightly in the yellow arc or 162 MPH. Surprisingly, this air speed holds up to 8000 feet. I now figure on 150 knots.

Several observations: It gets off and climbs much better. It seems to plane flatter and does not feel so draggy. Its quieter and smoother. I had the prop balanced; it took only two grams and I could not tell the difference. I cruise the prop at 2300 RPM rather than 2400 on the old, with little difference in airspeed. I am guessing that the long prop bites the thin air better with the extra blade at altitude.

A friend flew his 1959 250 HP Bonanza alongside of me and we were neck-and-neck, both of us at 24 squared. I am delighted with my new airplane. I still have the old two-blade prop. It would be interesting to install it and make a comparison. And, of course its a guy thing. Why not?

-John Mohr
Brandon, Mississippi

Reading your recent article about the three-blade propellers and speed, I had a V35A Bonanza with a three-blade propeller from 1968 to 1972.

At a meeting at the plant with the American Bonanza Society, one of the tech representatives told me that the three-blade propeller gave up about 1 MPH in cruise speed to the two-blade propeller.

This parallels marine information, where small speed boats have two-blade propellers. Thus, if speed is the only thing, youre right: A two-blade propeller is better.

-Louis Capozzoli
Baton Rouge, Louisiana

Airplanes vs Cars
For years I have read various articles about general aviation and product liability insurance, often with high litigation costs, as being the reason for the perceived demise of general aviation.

When a car is sold and has a manufacturing or design defect, the manufacturer (either on its own or as a requirement of the government) recalls the cars and fixes the problem at its expense.

When an airplane (or a part on an airplane) has a similar problem, a service bulletin or an AD is sent out and the problem must be fixed (often as a legal requirement) but the manufacturer seldom accepts the responsibility or cost and the end users must bear the expense. The ongoing problems with Hartzell propeller blades are examples.

These are not costs that can be spread over a large production run (often used as an excuse by manufacturers as a reason product liability costs are so high), because they are costs that affect each unit in the production run.

Why don’t airplane owners have the same protection as car owners? This is not a product liability issue or a warranty issue, it is a product quality, design and engineering issue. Could it be that some of the screaming about product liability is really an attempt to increase insurance profits?

I cant decide and the trial lawyers and insurance companies are constantly at odds over this, but I must say that I am suspicious.

I would like to make it clear that I am not a lawyer and I think that many lawsuits should be thrown out of court immediately. But on digging deeper into often apocryphal stories, one finds that there is a reason for most of the large judgments.

-Bob Gould
Kaneohe, Hawaii

Hey, Thats No 182
I am the proud owner of a 1963 Cessna 205. This aircraft is often mistaken by line personnel and others as a 206 and controllers want to call it a Stationair.

But I was truly amazed to read Richard A. Coffeys article on Building a Better Panel in the February, 1998 issue to find that I really owned a Skylane. Much to my surprise, the panel shown in the center picture on page 11 is installed in my 205. I did enjoy the article and can verify several points if you decide to go whole hog and redo your panel, instruments and avionics. First, hire a pro, like the folks at Aerotronics to do the design and installation.

Second, be very patient. Third, bring lots of money. But the result is we’ll worthwhile. Not only do you get to have friends and strangers admire your bird but you also get the fun of flying behind a well-designed panel with up-to-date avionics.

But please remember, its not a Skylane, a Stationair or even a Super Skylane. Its just a plain old 205.

-Scott Heck
Bozeman, Montana

El Nio made us do it. The photo was provided with no caption and it sure looked like a Skylane to us. Our apologies for the mix-up.

Champ Kudos
Ive had an excellent experience with an aircraft manufacturer and would like to share it with your readers.

I owned an FBO and new aircraft dealership for several years. I bought and sold new and used aircraft throughout the Western states. Very often, the manufacturer acted as though they were doing me a big favor by selling to me. This is certainly not the attitude of American Champion Aircraft, builders of the Citabria line.

Im just completing the purchase of a model they build and the whole experience has been outstanding. Champion is owned by the Mehlhaff family and they know how to treat a prospective customer. If you are interested in a real fun machine, give American a call. You wont be sorry.

-Dan R. Montgomery
Olympia, Washington

Gyro Sources
I found the article by Gary Picou in the January Aviation Consumer on gyro replacement strategies to be educational, informative and enjoyable. Good job.

I have a comment on the statement in the sidebar article (Replace a TC with an AI? Forget it, says the FAA): As for back-up AIs, the AIM 1100-series electric gyro is the only affordable choice were aware of. List price…is $3369 for a 14-volt, unlighted model.

R.C. Allen Electric AIs are regularly advertised in Trade-A-Plane for prices ranging from $1250 unlighted /$1450 lighted (RCA 26AK4, Chief Aircraft) to $1495 unlighted/$1595lighted (Pacific Coast Avionics). Whether these are 14V or 28V is not indicated.

Am I missing something? Even if these are 2 1/4-inch rather than standard 3 1/8-inch, the application, being an electrical back-up AI to a vacuum instrument, would be satisfied by either size.

-Vince Fischer
via e-mail

Nope, youre not missing anything. We are. Or we did. We simply overlooked those gyros because we had been informed, incorrectly, that they had been discontinued.