single engine safey

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As a student learning to fly in a 180hp C-172, I am gravitating towards the T-206 G, for
its forgiving handling characteristics, proven design, high DA performance and load
hauling capability.

I will frequently be flying out of some unforgiving areas, high altitude with forest and
canyon off the end of the field. I will be flying over rugged areas of AZ, UT and CO. So an
engine failure has more potential to have a nasty ending. Phil made the following
comment in a previous blog discussing piston engine reliability:

"In the old days, the theory was that a piston engine failed every 4000 hours and a turbine
every 40,000 hours. I think weメre up to closer to 1 in 200,000 hours for the turbines and a
carefully operated low performance piston engine (e.g., IO-360) is probably improved by a
similar factor (1 in 20,000?). East Coast Aero Club has around 27 airplanes and flies at
least 400 hours per year per plane, so in round numbers that is 10,000 hours per year.
Since Adam Harris took over as head of maintenance, which was quite a few years ago, the
club has not had any in-flight engine failures (or anything else that led to an off-airport
landing). Even with a piston engine, I think youメre more likely to run out of gas than to
have the engine stop due to mechanical failure."

Other than babying the engine, I am curious what types of maintenence procedures should
to be done to assure the absolute highest level of reliability in a single engine piston? I
was considering the da42, a safe and efficient design, but it doesn't have the cargo utility
that I want in order to carry passengers and bikes, skis, dog, etc. What procedures do East
Coast Aero Club's mechanics use in order to acieve such reliabilty?



-- Eric Whiteman, August 28, 2007


Our helicopters live in the ECAC maintenance hangar, so we learn about any problems with the airplanes over lunch with the mechanics. They often have a good laugh over things that pilots do, e.g., declare an emergency with ATC in VFR conditions because an alternator light came on.

How do they achieve good dispatch rate and safety? Partly by hiring the right conscientious people in the first place. Partly by not skimping; they replace anything that is questionable and they always get factory overhauled or remanufactured engines. Mostly, though, I think it is that they don't rely on one set of eyes. If Mechanic A does a 100-hour inspection, everything that he touched will be looked at by Mechanic B before the aircraft is returned to service. This catches a lot of missing screws, loose clamps, etc. The check mechanic will put wrenches on critical bolts to make sure that they are tight.

A DA42 at gross weight on one engine is a marginal performer. At high altitudes, if you do everything perfectly after an engine fails, you will still be sinking at 200 fpm or more. This is also true of the Piper Seminole and other trainer twins.

If you don't mind ridiculously slow cruise speed, the T206 sounds like a good choice for your mission and experience.

-- Philip Greenspun, August 29, 2007

Without meaning any offense to Philip, he should take into consideation that ECAC are not under any obligation to make such mechanical failure a public matter.

Piston engine failures that do not end in substantial airplane damage or injury are not required to be reported under Part 830, the SDR system is not obligatory for Part 91 operations, so things can be kept quiet. This is not specifically regarding ECAC but any place that rents planes for living.

Specifically, I assume that Philip wrote what he did regarding ECAC without knowledge of the full facts, as I know beyond any doubt that reality is different.

-- Tal Reichert, August 28, 2007

To Tal:

I am extremely curious to know how an engine-out and subsequent emergency landing wouldn't get reported in most normal circumstances?

There may be the rare, isolated incident where a pilot loses power on take-off and then makes it back to his/her departing airfield (without ever declaring an emergency???!!!) in one piece and doesn't bother reporting the situation, but I'd have think those would be very rare circumstances indeed.

If the average airplane/pilot combo had an engine-out and was forced to land somewhere other than the airfield that they had departed from it would seem to be highly unlikely that the incident could possibly go without being reported. In particular this day and time, with 24-7 news crews out almost everywhere. Also, considering most pilots would declare an emergency and also use the Mayday! distress call as frequently as they could manage during the emrgency landing the "frequent" unreported engine failures you write about seems unlikely. Please elaborate as to how all the non-reported engine-outages occur. Thank you. Regards, Mark

-- Mark Dalton, August 29, 2007