Unicom

July 2002 Issue




Water Over Trees

Stats may say trees are just as safe, but I’m going for the soft stuff.

After reading your article on ditching vs. going into the trees [Risk Management, May], I got to thinking about the choice I had over Bull Shoals Lake a few years ago. I was on an extended approach to Gastons’ Resort in Lakeview, Ark., from the north in our Cessna 140 when the carb began to ice up a couple of miles out at about 500 feet above water level.

Those 60-foot oak trees to the left looked pretty unforgiving compared to a ditching, and I remembered my answer a couple of years prior to the instructor at Arlington, Wash., during a C-172 checkride from Boeing Field.

He pulled the plug over the bay, after all hope of a return to Boeing was gone, smiled at me and said, “What are you going to do now?” I replied, “I’ll head toward a ditching as close to the shore as possible until you give me back my engine.” “Right you are, mate.”

Fortunately a liberal dose of carb heat and full rich brought the little O-200 back to life and we enjoyed Gaston’s Sunday brunch with dry clothes after all. Given a choice I would still opt for a close-to-shore ditching vs. tall trees as a much cleaner solution. Excellent article, though.

Finally, a quibble. An elementary physics book states kinetic energy varies with speed squared, not logarithmically. The plot (upper graph, p. 13) clearly shows this, and the same data plotted on log-log paper will be a straight line with a slope of 2, the exponent of velocity. I think there’s some confusion of terminology in your sidebar. The statement should read “...relationship between speed and energy is exponential (or square-law), not flat.”

-Andrew Smith
Via e-mail


We agree that a ditching close to shore would usually be our choice over a trip into the trees, but there are circumstances that could arise that could make the trees preferable. Frigid water, cliffs or water pounding on rocks come to mind.

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Ditching Details
I have enjoyed reading Aviation Safety for years but I don’t recall any stories about ditching. Have you published any stories about ditching accidents and how to handle them?

I am particularly concerned about an engine failure over the ocean, and the problem of getting out of the plane after a water landing. I have life jacket and a four-man life raft on board, but I am not sure what the best way is to get myself and others out of the plane safely in the event of a water landing. Thanks for checking this out.

-Jeff Fitzsimmons
Gainesville, Fla.


Our analysis of ditching statistics appeared in the October 1999 issue. For an excellent resource on ditching, including techniques, egress and equipment, see www.equipped.org/avsrvtoc.htm.

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Forced Landings, the Easy Way
With respect to forced landings, there’s a simple rule of thumb passed to me by one of those gray-beard test pilots (1950s vintage): Slow to best glide speed and maintain the VSI between 200-300 fpm. You will walk away from the airplane. If you have a constant speed prop, feather the prop.

-Gregg Monaco
Via e-mail


Maybe that worked in a tube-and-fabric 1950s airplane, but most airplanes will lose much more than 200-300 fpm at best glide speed with the engine out. If you’re going to follow such a laissez-faire approach to a forced landing, at least do it at minimum sink speed.

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Idiot Alert
In my 31 years of driving automobiles I have run out of gas once. There was no safety issue and only minimum inconvenience.

With all of the stories of fuel exhaustion accidents it is time someone made the statement you have finally made in “Speed Kills (At Least It Hurts)” that “… if you run an airplane out of gas, you are an idiot …”

It is good to see that you keep speaking the truth, and God forbid I ever have to eat my words. Keep up the good work.

-Greg Corrado
Seattle, Wash.


Did we say that? We meant “… if you run an airplane out of gas, you are a careless idiot …”

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Spin? Maybe Not
As an old pilot from the days when a flight instructor had to do precision spins on the check ride, I’ve bemoaned the lack of stick-and-rudder training in the current crop of pilots.

In 1999 a good friend of mine was killed in a crash of a Civil Air Patrol C-182 in which the wreckage indicated the airplane crashed inverted. I wondered how a good pilot could get upside down inadvertently, so I went out and did some test flying.

After many attempts, I got it. It was not a stall/spin but a torque roll. Establish a power-on climb and at about 10 knots above the stall start a roll to the left, keeping the ball centered. If the plane stalls in the roll you’ll flip over on your back. Top rudder won’t stop it, only chopping the power and applying rudder will bring the plane back upright. If you are less than 1,000' feet agl it’s all over.

As far as I know, this hazard is unknown to most pilots. A CAP Cessna 182 on a search is the most likely plane to get into this problem, because most search pilots are flying at 90 knots, with the MP in the bottom of the green and 10 deg of flaps to keep a reasonable deck angle.

If you add power, the nose comes up and speed bleeds off. Start a roll into a left turn, and if it stalls you are dead.

-Don Barnes
Sunriver, Ore.

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Pick Fire Responses Carefully
I just read “Fire in Flight” [Risk Management, April] and found it to be an excellent article about a problem that is too often given too little thought. However, I’m concerned about the statement, “In general, you should always follow the (manufacturer’s) recommended procedures, unless in your judgment the procedure would make the emergency worse.” Let me say that you had better be very sure about what you’re doing before you go against any recommended procedures.

A number of years ago I was employed by a manufacturer of light twin aircraft when the issue of engine fires surfaced. I was part of a team that did some investigating in this area to determine the best course of action to take in the case of an engine fire. We investigated the effects of the position of flaps, gear, cowl flaps, and even such things as opening cabin vents and windows.

We found that opening the pilot’s small window (as some had apparently done) for the purpose of clearing smoke from the cockpit would actually lower the pressure in the cockpit and a fire could be drawn from the nacelle area through the wing root up around the center console, creating a virtual inferno for the pilot and front seat passenger.

There was evidence that this may well have happened in at least one case. The recommended procedure is to leave the window closed. Opening it may well escalate a serious situation into a fatal one.

The evidence also seemed to indicate that an engine nacelle fire on a twin could result in the loss of a wing in less than five minutes. Out of that whole process it became my firm conviction that the first order of priority in the case of an engine fire was to head for the ground and begin troubleshooting and emergency procedures on the way down.

If the fire goes out, maybe you can keep going, but if not, land immediately. I’m aware of at least two fatal accidents in which a wing burned off as the pilots were on their way to land at “the nearest airport.” My philosophy? If an airport is in the vicinity fine, but if not, land anyway and take your chances on the terrain, because the wing might well burn off on your way to the “nearest airport.”

-Jim Lush
Via e-mail


Good advice. We recommend people follow the manufacturers’ procedures in most cases, but because the testing – and POH – cannot cover every possibility it’s essential to apply some common sense to the recommendations in some circumstances. As you say, however, being extremely careful about trumping the checklist is vital.

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Popping the Prop
I read about the 7AC running away from its pilot [Preliminary Reports, March]. I would like to pass on a hint from the good old days and maybe it will help end runaway airplanes.

I started flying when most airplanes were started by hand-propping. If we had help, we got into the cockpit and someone pulled the prop after the proper preliminaries. Alone, we’d try to prop from the back side of the prop, with the left arm inside the door (works on a Cub, anyway). On other airplanes, tie down the tail.

But the real secret was simply to shut off the gas valve. There would be plenty of fuel in the carb bowl and the fuel lines for the engine to start and idle for a few moments.

No airplane ever got away from me, but over the 46 years I was an airport manager, flight instructor and commercial pilot at my city airport, five airplanes got away from other pilots.

-Donald Fitzwater
Beatrice, Neb.

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Expecting Errors
I found the article “Expectations” [Accident Probe, May] very interesting and informative. The accident could have been avoided had the pilot of the 172 simply said he was No. 2 at Foxtrot when he called ready for takeoff.

Many years ago, I read statistics that indicated that about 80 percent of general aviation accidents are attributable to pilot error. A non-pilot friend of mine commented that this doesn’t say much about pilot skills. He was taken aback when I said I wished accidents were 100 percent pilot error.

If accidents were 100 percent pilot error, that would mean ATC would never make a mistake and there were no mechanical failures that would kill me.

Since we will never get to the point where all accidents are the fault of the pilot, we must do all we can to assist ATC and other pilots to do a good job. It’s easy to get complacent due to the usually excellent performance of the system, whether it’s ATC, mechanical functions or whatever. We would do well to adopt the Coast Guard’s motto: Always vigilant.

-Russell Smith
El Paso, Texas


We applaud the goal of zero accidents caused by ATC or mechanical failures. Unfortunately, preventing accidents also requires both sound pilot judgment and sound piloting skills, and we’re not likely to get those perfect any time soon.