Fatalities: Rentals vs Owned?

"Andrew Gideon" wrote in message
news
Would you know of evidence that actually backs up the statement that
aspects of MX are enhanced when utilization is higher?

Only my personal experience, which is not what I'd call "closely
documented". That is, it's basically anecdotal.

However, my experience suggests that maintenance can be grouped into two
broad categories: wear and tear, and sitting around. For the things that
are "wear and tear", the more you fly the plane, the more you spend. This
includes things like oil changes, lifetime-limited parts (lights, vacuum
pump, brakes, tires, etc.) The point of my previous statement is that there
are more "sitting around" items on the airplane than one might think.

Note that this distinction is somewhat artificial. That is, in most cases
that I can think of, the "sitting around" aspects either directly or
indirectly affect some "wear and tear" aspect. In that sense, it's hard to
separate the two. But there is definitely "wear and tear" that is a
consequence of "sitting around". In that sense, I blame that on "sitting
around", not "wear and tear".

One thing that always crops up when I don't fly my airplane as much as I
should are the seals in the hydraulic system. My airplane depends on
hydraulics for gear operation, flap operation, and trim operation, so it's
an important system. When the airplane sits for awhile, it takes a
couple of flights before I see the hydraulic system reliably maintain
pressure. During those flights, every now and then after some hydraulic
component is operated, the control valve doesn't seal completely and there's
a bit of leak-down, causing the hydraulic pump to run more than it otherwise
would. Since the hydraulic pump is a "wear and tear" item, this translates
in a subtle way into a higher cost for maintaining that part. In addition,
the hydraulic seals themselves suffer from disuse.

In a similar way, seals on the landing gear oleo struts are affected.
Through lack of use, they are harmed, and the more they are used, the less
they deteriorate. They are designed for a specific operating environment,
and letting them sit around without working reduces their lifetime. Yes,
using them also reduces their lifetime, but my experience has been that
their lifetime is actually quite good when used as designed, and not very
good when they aren't.

Another example is the tires. When the plane sits, the tires take an uneven
"set". This doesn't take long to happen, but if an airplane is flown
several times in a single day, this is essentially eliminated. Any amount
of time less than this allows it to happen to some degree. When the tire is
unbalanced like this, it affects the wear on the tire in an obvious way, and
the rest of the airplane in a less obvious way (through increased vibration
and direct stress on the connected parts).

These are just examples...one can go through all of the mechanical
components of the airplane, and identify a number of similar items. It's
been my experience that the "sitting around" maintenance items are not
restricted to engine corrosion. Not that engine corrosion should be
discounted, but it's not the only thing. And on top of all that (as if that
weren't enough proof that flying more often always helps at least some
maintenance costs) to some extent corrosion starts the moment you shut down
the engine...it's true that on the whole, the engine remains protected, and
corrosion really accelerates after some longer period, but that doesn't mean
that there is *no* corrosion.

So, it doesn't surprise me at all that regardless of actual flight hours,
the more the flight hours the better, even once you pass the mythical
"anti-corrosion" threshold. As you note, your club's experience bears this
out.

All that said, note that I was simply talking about some aspects of
maintenance, and not trying to address the total cost per hour of
maintenance. I do suspect that above some reasonable utilization, the cost
per hour is relatively constant. You may manage some marginal improvement
with even higher utilization, but I'm sure there's some point of diminishing
returns. I admit, as an owner with a lot of non-aviation distractions in my
life, I have only even approached this point a handful of times during my
ownership, and I have never passed it. For owners like me, it is clear
that a well-used and well-maintained FBO airplane is likely to be in at
least as good shape as my own airplane.

My main point is that I don't believe one can make broad generalizations
about privatele owned versus FBO-owned airplanes. There's too much
individual variability among each, and most of the time a well-maintained
airplane is just not going to be a factor in an accident, regardless. It's
the neglectful owners, whether an individual or an FBO, that are a problem,
and there too many examples of each type for anyone to claim that one is
clearly worse than the other.

Pete

"Andrew Gideon" wrote in message
news
On Sun, 22 Oct 2006 20:44:23 -0700, Peter Duniho wrote:

One area in which FBOs have the advantage, however, is utilization.
Many
aspects of maintenance are actually *enhanced* when utilization is
higher.
In these respects, busy FBOs have a clear advantage over owners too busy
to fly often.

Once a plane is flying enough to avoid corrosion, is there a benefit to
increased utilization?

I *believe* that there is. We'd one aircraft in our partnership that, for
one year, was flown significantly less than the others. It's MX cost per
flight hour shot up. Once it was being flown more, the hourly cost came
down. Note that the rate of flight never went down enough to worry about
corrosion.

Now, this is counterintuitive to some of my partners. They believe that
MX cost per flight hour should be roughly constant regardless of the
number of hours (once one is beyond the corrosion point).

I happen to think that the formula is more complex than MX/hour being a
constant. I suspect that MX/hour goes down for increased hours. But all
I have is that one experience and a gut feel.

Would you know of evidence that actually backs up the statement that
aspects of MX are enhanced when utilization is higher?

- Andrew

Your aircraft experience is identical to my automotive experience, and also
to the second hand information that I have received about aircraft. Just as
one example, the airport rumors state that highly utilized engines routinely
reach their projected TBO in excellent health; while the 100 hour per
engines almost never do. I suspect that the 200 to 300 hour per year
engines also fall short of TBO, but even anecdotal evidence is hard to find
in that range.

Peter
Also curious what other have seen and heard.

Jay Honeck,
I think you're off-base on this one. People who own planes leased back to
an FBO, and even FBO-owned planes, are probably maintained to a highjer
standard than most "owner-flown-only" planes. Reasons? 100-hour
inspections which are mandatory if rented out for flight training, etc, and
the ever-present threat of liability suits if anything goes wrong and a
renter is killed/injured.

Having had over 14 years of leaseback experience with my C-172P, I believe I
can speak with some credability here. Of course, it does pay to lease to a
reputable and careful FBO, but would any logical person do othrwise?

Jay Somerset [lots of us Jays around, it seems :-) ]


On 22 Oct 2006 14:30:43 -0700, "Jay Honeck" wrote:

I don't know any other way to say this: Because that FAA rule is
stupid.
Anti-authority, anyone? It doesn't matter if the rule is stupid, it's
not an excuse for breaking it. Not to be dramatic, but do you think
having a DH on an approach is stupid?

Comparing silly landing light regulations with life-and-death flight
rules does little to further the discussion.

But back to the topic: I see plenty of owners dinking around with their
planes inside their hangars every weekend, checking this, straightening
that, making sure every zip tie and hose is perfect. Quite frankly,
pride in ownership is one of the three reasons that I think owning a
plane is worth every penny, and I've spent many happy hours in my
hangar doing nothing but polishing parts that no one else (but my
mechanic and me) will ever see.

During this quality time, I've occasionally found little maintenance
issues that would otherwise go unnoticed. I've found exhaust pipe
clamps loose, drippy hoses, and loose electrical connections while
farting around inside the engine compartment, and in each case I have
been able to rectify them BEFORE they became a maintenance problem.

This is unlikely to happen as a renter. Unlike John Smith's happy
situation (where he belongs to a club with 25 rental aircraft that are
meticulously maintained) around here the rentals are all either owned
by the FBOs, or they're put on "the line" as a lease-back aircraft.
Not only would you have difficulty finding a renter pilot who would be
willing to take the time to do this type of stuff, but the FBO rules
would most likely prohibit it from happening.

An example: When I was a renter, Mary and I had a favorite plane, a
sweet little Cherokee 140 with a fresh engine. After six months of
renting it, the thing was an absolutely cosmetic disaster, with bug
guts hardened on to all the leading edges, and topsoil pounded into the
carpet on the floor.

Knowing what a shoe-string budget the FBO was running on (they weren't
about to pay a line boy to clean it), we proposed doing a
"plane-washing party", where all the renters would come out and spend
an afternoon cleaning that poor old dawg. We even volunteered to
provide the beer, and do a cookout (remember, this was in Wisconsin,
where beer at the airport is not only okay, it's *expected*), as an
incentive to get renters to participate.

The idea was met with absolute incredulity from the other renters.
Their attitude was, quite simply, "Why would I work to clean someone
else's plane?" -- and that was that. There was no pride in the machine
-- it was just a tool that they were borrowing from someone else --
period.

Saying that this "not my problem" attitude isn't common among renters
flies in the face of my personal experience, which isn't to say that
there aren't exceptions to the rule. But, again, IMHO most rental
birds are "ridden hard and put away wet" -- and there should be some
way to quantify this when comparing accidents due to mechanical
failure, if only the FAA would track it.

Are you implying that the government specifically wants the answer to the
question you're asking to remain unanswered? For what possible reason would
they care whether the question is answered or not?

The government (the FAA) is famous for not asking the simple question:
"How many hours did you fly since your last medical exam?" on the
medical application form. This leaves everyone in (and outside) the
government guessing how many total hours were flown last year, or the
year before -- and results in tremendously inaccurate (probably)
estimates. (Richard Collins, of Flying, has been railing about his for
years.)

Why don't they ask? No one seems to know -- but perhaps because they
are afraid of the answer?

Now, are these same folks not putting this "rental vs owned aircraft"
question on the accident reports for the same reason? I don't know --
but it sure seems like an odd question to omit.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Jay Honeck" wrote in message
ups.com...
Are you implying that the government specifically wants the answer to the
question you're asking to remain unanswered? For what possible reason
would
they care whether the question is answered or not?

The government (the FAA) is famous for not asking the simple question:
"How many hours did you fly since your last medical exam?" on the
medical application form.

"Famous"? I think that word does not mean what you think it means.

This leaves everyone in (and outside) the
government guessing how many total hours were flown last year, or the
year before -- and results in tremendously inaccurate (probably)
estimates. (Richard Collins, of Flying, has been railing about his for
years.)

It does leave people guessing, yes. That's what happens when one doesn't
survey the information desired. One has to guess.

Why don't they ask? No one seems to know -- but perhaps because they
are afraid of the answer?

"Perhaps"? And perhaps they are not. What's your point?

Now, are these same folks not putting this "rental vs owned aircraft"
question on the accident reports for the same reason? I don't know --
but it sure seems like an odd question to omit.

You have completely failed to address ANYTHING in the post to which you
replied, including the direct questions to you that you quoted in your
reply. Shall I apply the same suspicion to my interpretation of your post
as you are applying to the FAA?

Pete

I think what you're actually trying to prove is that those of us who
rent abuse planes and don't take any pride in taking care of them.
Think like that if you wish, but it's an elitist attitude and one that
does GA no favors. Owning an aircraft does not entitle you to violate
any regulation, especially Part 43 or 21...and unfortunately, those are
the ones I see owners violating most frequently. I've refused to
instruct owners who perform illegal maintenance, and I've refused to
fly with renters who bust minimums. It has nothing to do with who owns
the plane, and everything to do with the mentality of the pilot.
You've proven in this thread that you think you are above the FAR's,
which is pretty sad.

Eh? How did you make THAT leap? Or ANY of those leaps?

Emily, that's the goofiest, most twisted out of context reply I've read
here in many years -- and that's really saying something. You clearly
know little about airplane ownership (and not much more about renting),
yet you feel qualified to spout FARs?

If you think that an owner polishing and pampering his/her bird, making
sure that every working part is functioning perfectly at all times, is
tantamount to "performing illegal maintenance" you have officially
announced your lifetime membership in the "Box of Rocks" category.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

You have completely failed to address ANYTHING in the post to which you
replied, including the direct questions to you that you quoted in your
reply. Shall I apply the same suspicion to my interpretation of your post
as you are applying to the FAA?

I replied to the one part of your post that required a response.

The rest of your post could be more or less summed up as saying "There
are good owners and renters, and there are bad owners and renters."
Which is true, of course, but sheds little light on the subject.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Jay Honeck" wrote in message
ps.com...
You have completely failed to address ANYTHING in the post to which you
replied, including the direct questions to you that you quoted in your
reply. Shall I apply the same suspicion to my interpretation of your
post
as you are applying to the FAA?

I replied to the one part of your post that required a response.

No, you did not. You answered neither the question "Are you implying that
the government specifically wants the answer to the question you're asking
to remain unanswered?" as well as the question "For what possible reason
would they care whether the question is answered or not?"

Those were the only two portions of my previous post that you quoted, and
you completely avoided those questions.

The rest of your post could be more or less summed up as saying "There
are good owners and renters, and there are bad owners and renters."
Which is true, of course, but sheds little light on the subject.

It sheds quite a bit of light on the subject, inasmuch as it suggests that
the answer to your original question is that no, there is no significant
difference between the fatal accident rate for rental airplanes and owned
airplanes due to maintenance.

Pete

Jay Somerset wrote:

Jay Honeck,
I think you're off-base on this one. People who own planes leased back to
an FBO, and even FBO-owned planes, are probably maintained to a highjer
standard than most "owner-flown-only" planes. Reasons? 100-hour
inspections which are mandatory if rented out for flight training, etc, and
the ever-present threat of liability suits if anything goes wrong and a
renter is killed/injured.

Having had over 14 years of leaseback experience with my C-172P, I believe I
can speak with some credability here. Of course, it does pay to lease to a
reputable and careful FBO, but would any logical person do othrwise?

I believe I have a little credibility, too -- I worked at a flight
school and own an airplane. After a relatively short time of airplane
ownership, it was evident that there is a big difference between the
meticulousness of mechanics. There can be a huge gap between the lengths
two different mechanics will go to inspect and sign things off.

IMO, it's wrong to *assume* that rental airplanes are safer just because
100-hr inspections are mandatory for those aircraft. It is a logical
assumption, but not necessarily an accurate one. Depends on who is doing
those 100-hr inspections. Is it the same mechanic every time, one that
is familiar with that airplane? or is it a different guy each time? Is
it a trainee doing the work under the supervision of an A&P, IA? or is
it the IA himself?

Privately-owned airplanes generally have a couple of mechanics that do
*all* the maintenance in conjunction with the owner. They all become
familiar with the nuances of each airplane. And some privately owned
aircraft are looked at by mechanics as often, if not moreso, than rental
aircraft.

Think about it -- if you fly 2x/week for 2 hours each time, that's
roughly 200 hours/year. There are some rental aircraft that don't fly
much more than 4 hours/week, if that, as well (some much more, of
course). So how much more maintenance is that rental getting, just
because they get an inspection every 100 hours? In a year, they get one
100-hr and an annual. The privately-owned airplane with the same amount
of hours gets an annual, but with oil changes every 25 hours, most
owners and mechanics are repairing other squawks and checking various
things during those oil changes as well. I've seen rental aircraft in
for oil changes -- they get the oil changed, PERIOD!...no additional
looking around unless someone is there with a squawk list.

I don't buy for a second that rental airplanes are automatically safer
just because they have 100-hr inspections. They are indeed insured for
more because of the threat of liability ... but ... automatically safer?
I don't think so.

Why don't they ask? ["How many hours did you fly since your last medical exam?"]
No one seems to know -- but perhaps because they
are afraid of the answer?

Maybe it's none of the government's business.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.