Old rental planes ?

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Hi Phil
What is the oldest rental single engine plane would you feel safe
to fly in ?
As far as renting from a flight school or fbo - would a single
engine plane
like Piper or Cessna mfg'd in 1979 be too old or really
pushing it ?

How bout- how much airframe hours is probably too much ?
Like 5000 or 10,000 hours or what ?
What about engine time - how much is too much ?
If planes are maintained - they have to do an annual
every year by FAA rules don't they ?

How long do they keep these planes flying ?
Are they really that safe once they get over 20 - 25 + years old ?
How can you tell or can't you for sure ?

-- jim kenn, February 18, 2010


The inspections will be every 100 hours for a commercially operated aircraft. There is no FAA limit on engine time for Part 91 flying (which includes flight school/rental), though the manufacturer will recommend an overhaul interval of about 2000 hours. East Coast Aero Club buys factory overhauled engines at the recommended intervals. A school trying to save some money might get a third-party overhaul done at 2500 hours.

You'd really have to hang out with the flight school mechanics to figure this out. After 30 years the plane's performance will depend more on who has maintained it than on who designed and built it. A good airplane mechanic is usually someone with a high IQ but a low tolerance for sitting passively in a classroom listening to a unionized civil servant lecture. You should get the impression that the folks maintaining the airplane are at least as intelligent as anyone with a desk job, a lot more patient, and generally more diligent and detail-oriented. The logs should be clear and complete (any flight school should be happy to show you the maintenance logs as indeed they have to be shown during FAA checkrides).

Finally you should evaluate the kind of flying that you're doing. I wouldn't take a 1979 plane with a vacuum pump and single attitude indicator into the clouds, though of course there are plenty of folks who will. But I might be happy to take that plane up on a beautiful VFR day for pattern work or flying around the Midwest where it is always possible to land in a field.

-- Philip Greenspun, February 18, 2010

All aircraft must have an annual inspection (FAR 91.409). Engine manufacturers specify a time-before-overhaul (TBO) for their engines. For the Lycoming engine on the current Cessna 172, the TBO is 2,000 hours. Only Part 135 (charter) operator must follow the manufacturer's recommended TBO. For Part 91, which includes rental, the TBO is just a recommendation. You can look in the logbook to see when the engine was last overhauled or remanufactured. I would not fly an aircraft with the engine beyond TBO. Of course, if the FBO won't let you inspect the logbooks, don't rent the aircraft.

I believe Lycoming's recommendation includes that the TBO is increased by 10% if the aircraft flies at least 600 hours per year.

Some aircraft have lifetime limits on their airframes, while others do not. The Cessna 172, for example, does not, so the airframe can keep flying indefinitely.

I thought it was interesting that the Cessna Mustang also has no lifetime limit. Many pressurized aircraft, like the King Air, do have limits. On their website, Cessna talks about the testing required to certify their airframe with no lifetime limit.

Other examples are Cirruses, which do have a lifetime limit, and Diamonds, which do not.


-- Todd Ramming, February 18, 2010

For my PPL training back in 1993 I flew a one year-old AG-5B Tiger. It had an intermittent electrical failure that caused me to learn to hand-prop well before my first solo. The Tiger became unavailable shortly after my checkride, and for many years I flew 1963-1976 vintage airplanes, i.e. 20-35 years old machines. I never thought of them as old, but some of them had worn-out seats and troubled avionics. But regarding age, I simply had no alternative.

Today I still fly old planes - I regularly fly a pleasant and well-maintained PA-28-140 from 1966 as an instructor. I also fly different glass panel equipped planes less than 5 years old. I don't think there is a strong correlation between aircraft age and risk, but I do appreciate better redundancy in newer planes when IMC.

Referring to Philips example, I do actually part-own a 1979 Piper Dakota with a single vacuum driven attitude indicator, and I frequently fly it IFR. But I do realize the increased risk in that. Two years ago the vacuum pump failed right after departure as we entered cloud about 500 ft AGL. It happened on my recurrent IFR training flight, and that was the best partial panel training imaginable, but it made me think - and keep up on partial panel pproficiency. This kind of risk is all but eliminated by glass cockpits.

One thing speaks in favor of old planes - they tend to have a greater useful load than comparable newer ones.

-- Henrik Vaeroe, February 19, 2010

In addition to the above, here is some other info.

The age of some airframes is a an issue, but usually, that is not the most important factor. Like Phil said, it's maintenance. Any aluminum plane over 10,000 hours is going to be suspect. Some Pipers have total airframe lives, and Beeches have some pretty serious frame parts that need replacement. Cessnas are likely to last double that mostly due to the supported wing. Cirrus has an airframe life, I believe it's due to some of their composites. Lancair/Columbia and Diamond used different composites with no life limit. Mooney's have steel frames, and the only issue is a likely need to replace the jack screw at some point. Other than the inspecting the logs and the plane, you can also tell by the feel of the plane. If it doesn't fly true, it's likely bent. If it's bent, it's closer to breaking.

Many schools fly over TBO, and that isn't as big an issue as some people would make of it. If they have a large, professionally run operation which otherwise engenders trust, I wouldn't worry about over TBO. OTOH, if there are lots of little repairs that are being postponed, AND the plane is over TBO, then I would simply go elsewhere. Those guys are putting money over safety.

Overall, I look harder at the school than the individual plane. Also, you often get what you pay for. The dumbest thing is to look for the cheapest school or the cheapest plane. Renting a newer plane is likely the better deal. Why pay over $100 an hour to fly in a rattle trap when you can likely pay an extra 20% to fly in a much newer, nicer plane? Is your goal to get a license to get a job, or to enjoy aviation? If it's the latter, forget going cheap. It's a bad value.

-- Eric Warren, February 19, 2010