Budget Retracts - Anyone own a Sierra or Comanche 180?

Henry A. Spellman wrote:
: The Comanche line started with the 180, so the whole aircraft was
: designed with the 180 hp engine in mind. A year or so later, the 250
: came into existence. But the Lycoming O-540 is quite a bit heavier than
: the O-320, so the 250 seems a little heavier in pitch, especially in the
: landing flare. The 250 is really quite good, it is just that the 180 is
: almost perfect.

: I have only flown a 180 twice, but I could discern the difference from
: my 250 that I have owned for over 20 years. The difference is slight,
: but it is there.

Hrm... having flown a 250 a couple of times with a friend that owns one, I can
say it sure is sweet. Granted the retract and CS prop would help, but 180hp on a PA24
seems like it would be awfully marginal... my PA28-180 hardly has power to spare. The
airframe on the PA24 is about 400lbs heavier than my PA28 IIRC, with only 150lbs more
gross. Sounds like a 3-place retract.

The 250 on the other hand climbs great no matter what the load it seems.
There is such a thing as a "resonant design" for aircraft. On the PA28, I'd argue
it's 180hp. For the PA24, it's 250. For a 172, probably 180hp as well.

As far as fuel flow goes, just because you have a bigger engine doesn't mean
you need to cruise with it. With only 60 gallons on a stock PA24 though, it'd be a
little bit short on range.

-Cory


--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

wrote:

The
airframe on the PA24 is about 400lbs heavier than my PA28 IIRC, with only 150lbs more
gross. Sounds like a 3-place retract.

I can't disagree with that. But for many missions, that is just fine.


As far as fuel flow goes, just because you have a bigger engine doesn't mean
you need to cruise with it. With only 60 gallons on a stock PA24 though, it'd be a
little bit short on range.

60 gallons is fine for the Comanche 180. At roughly 10 gph, that is 6
hours, which is much longer than most people want to sit. The early
models of the 250 (1958 through 1960) also had 60 gallons, which is not
enough at 12 to 14 gph, particularly for IFR trips. After 1960,
virtually all the 250 and 260 models had 90 gallons. Many of the pre
1961 aircraft have added tip tanks for an additional 30 gallons and a
gross weight increase of 200 pounds (less for post 1960 models). There
is also a baggage compartment tank available (20 gallons).

I agree with you that the Comanche 250 is a fine machine. It was my
choice. But the OP specifically mentioned a Comanche 180. The 180 also
has its place and, in some circumstances, is a superior choice than a
Comanche 250.

Hank
Henry A. Spellman
Comanche N5903P

Hello to all. I am new to this board and have my own aircraft
maintenance business. I work on mostly Pipers but also a Sierra that
may be for sale soon. I think you would find that the 180 Comanche is a
fine plane but you need to have it maintained by someone who
understands the landing gear system. So many of the old ones have been
bellied in at one time in their past. The Sierra does have a roomy
cabin and a short CG range. I had to change the landing gear doughnuts
on this model and it's not a job I want to do again any time soon.
First of all, you have to rent a special tool from Beech and they want
a $2000.00 deposit before they will send it to you. I think it cost
about $200.00 to use it plus the shipping charges both ways. If you
don't change the doughnuts ($900.00 worth) when they are sagging, you
might find the gear don't fit in the wheel wells they way they are
supposed to. The gear may or may not extend all the way when you leave
the ground, and one or the other will hit the up lock bracket and stay
there, instead of snapping into place. I changed every oring on the
hydraulic system cylinders (at owners request) and found the retract
cycle went from over 30 seconds to 14 seconds. Someone had put an oring
in the left cylinder that was too skinny to fill a groove on the
piston. I once did a prebuy on a Sundowner and found intergranular
corrosion on the left spar in two places. Aft side, lower web, near the
tip and just outboard of the fuel tank area. Beech has an approved
repair kit for this so you know it has been seen before. Also, don't
buy one of these planes with a fuel stain under the wings. Leaks can be
hard to fix in the wet wing fuel tanks. Finally, show me a plane where
they had to hang a ball of lead ballast on it and I'll show you an AD
note. This goes for other brands too.

wrote:

I think you would find that the 180 Comanche is a
fine plane but you need to have it maintained by someone who
understands the landing gear system. So many of the old ones have been
bellied in at one time in their past.

Of course, they're ALL "old ones".