Jim Newton wrote:
I would like like comment on whether it is a good idea to use a Continental
powered C182 as a tow ship that would be mainly used to tow the Schweizer
2-33 at sea level airports. I content that the tow speed would not be
comfortable for a 2-33 and that overheating of the continental engine would
be a problem in the summer. I'd like to convince those who might make the
decision to only use our Cessna 172, 180hp Lycoming conversion. I have no
experience with a 182 as a tug.
Jim
We use a 150/150 (with bare aluminum) and a 150aerobat/180
for towing 2-33s and L-13s from a sea level airport,
and do OK, even in 100+ degree heat of the summer.
We do use the whole 3300 feet of runway, however, and are fortunate to
have few obtacles (ok maybe a 3 foot fence) and flat
terrain on the departure end.
I'd personally pick a 172 180hp with a correctly pitched climb prop
over any contant-speed prop for towing, really because of expense.
The bit of added inefficiency from a fixed pitch prop seems to
me a small sacrifice for the weight savings and maintenence
ease.
The other thing to really do is to keep the weight of the airplane
as low as possible. Less weight = more climb and is a cheap way
to do it.
I am NOT an A&P, but I did a lot of work to my own 172 under
supervision.
I pulled out the old AN gyros, and replaced the old heavy
vac pump, and pulled out my huge, bulky, heavy avionics
and installation kits and harnesses, and rotted, heavy carpeting,
and I redid my seats and interior.
I also flew it a LOT with less than half tanks. Since
I leaned the same way all the time, my tachometer was
an extremely accurate way to measure fuel consumption (within
a half gallon per hour 100% of the time).
The lightest 172 would have NO avionics or instruments
except day VFR, completely stripped paint, no interior,
an electrical system removed, a lightweight starter installed,
and be started off a portable battery (good for only a few
starts), perhaps in the aft baggage compartment for weight
and balance. One would find the lightest "midget" pilot
and fill the tanks with the minimum fuel required. All
the seats except for the pilot would be removed.
And no wheel pants. I bet a 1970s 172 would have
an 1100 to 1200 pound empty weight, and probably
double or triple the climb of max gross, depending on the
density altitude...
Could you get a mechanic to sign this off? Well, some of
it you could. But this is just an example to show you
what adds weight. You get the idea, right? Less weight
is the equivalent of free horsepower, so if you'd be
willing to spend $12,000 for a bigger engine, can't you spend
a few thousand $s to make the plane weigh less?
For the power part, the Wolf remote oil coolers are really great for
cooling the oil, and I used an EGT/CHT, which is my first choice
for an "optional" instrument. Next, I found that a meaty prop,
of the right size and pitch, really makes a difference, and
is reasonably priced ($a few thousand, fixed pitch of course).
Some towpilots really like the iridium (?) spark plugs too,
especially for the bottom cylinders, for less fouling.
If you're buying a plane, I'd weigh it first. Twenty years of
"corrosion X" applications can weigh a lot. So can
one or two paint jobs. I suspect a low time, original
172 is pretty hard to find, but I got one, and at a steal because
the paint and interior were original (and trashed).
Of course a 180hp conversion would have been some extra $$$$s
and some weight, I suppose.
If I already had a 172 as a towplane, I'd take the extra
$$$s I was considering for a 182 and instead put it into a
super tune up. Timing just perfect, maybe a top overhaul,
check and pitch a beautiful prop, a second set of plugs
cleaned religiously, remote oil filter/cooler, EGT/CHT,
clean, new, perfectly contoured baffling, etc....
Yeah, and polish it with a diaper, that's the ticket :P
P.S. Our tugs both have wheel pants on them. Not quite
sure why...I guess I'll ask...
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