Budget Retracts - Anyone own a Sierra or Comanche 180?

wrote:
How about an early Bonanza? I paid $27,000 for my 54 E35 in 1996 and
it is worth about $45,000 today. I go a good 10 knt faster than my
friend's Arrow at lower fuel flow. I flight plan 145 knt @ 10.5 gph,
and it true out at 150 on most days. Parts are more expensive but you
don't need them as often. It is harder to find A/P who knows about
Conti E225 engines but they are out there.

Old Bonanzas are retro, and, as you say can be had for about the same
price as the Comanche 250. But when you compare the cost and availability
of parts, the Continental Vs. the Lycoming O-540, another 5knots in cruise
as well as maintenance items the PA24 has the edge.

You will be paying a big price for retract, in initial cost,
maintenance and insurance. Extra speed for 1 to 2 hour trips doesn't
amount to much. If the wife wants 2 doors, you should probably get two
doors.

On 5-Feb-2006, "Doug" wrote:

You will be paying a big price for retract, in initial cost,
maintenance and insurance. Extra speed for 1 to 2 hour trips doesn't
amount to much.


If you fly over 100 hrs/year the savings in fuel costs with RG compared to a
FG with similar performance will more than offset the added costs for
maintenance and insurance.
--
-Elliott Drucker

wrote:
On 5-Feb-2006, "Doug" wrote:


You will be paying a big price for retract, in initial cost,
maintenance and insurance. Extra speed for 1 to 2 hour trips doesn't
amount to much.



If you fly over 100 hrs/year the savings in fuel costs with RG compared to a
FG with similar performance will more than offset the added costs for
maintenance and insurance.
I'd really like to see some number to support your conclusion. By my
estimates 100 hrs * 11 gals per hour = 1100 gal per year. RG decreases
fuel need by 5% or 55 gal * $3.50 = 192.50 per year in fuel savings.
From the numbers throw about by my aircraft owning buddies the delta in
ownership costs for a retract are much more then that.

Assumptions in above: Fuel burn is about the same for 180HP engines in
Comanche 180 and 172s with 180HP engine. Increased speed reduces need
for fuel by 5% by higher speed in cruise, climb fuel burn is the same.
Big YMMV is added

John Theune wrote:
: I'd really like to see some number to support your conclusion. By my
: estimates 100 hrs * 11 gals per hour = 1100 gal per year. RG decreases
: fuel need by 5% or 55 gal * $3.50 = 192.50 per year in fuel savings.
: From the numbers throw about by my aircraft owning buddies the delta in
: ownership costs for a retract are much more then that.

: Assumptions in above: Fuel burn is about the same for 180HP engines in
: Comanche 180 and 172s with 180HP engine. Increased speed reduces need
: for fuel by 5% by higher speed in cruise, climb fuel burn is the same.
: Big YMMV is added

Not to be too argumentative, but 5% might not be the right number. A quick
example:
http://www.risingup.com/planespecs/i...plane432.shtml
http://www.risingup.com/planespecs/i...plane427.shtml

That's a PA-28-180 vs. a PA-28-180R. Cruise of 119 kts vs. 141 kts. That's
18% improvement in speed. Others are similar around 15%. So, multiply your fuel
savings by a factor of 3 and you get $600/year. That's starting to sound more in line
with the additional costs of a gear swing every year, some more lube, and a
replacement part averaging every 5 or so.

Just food for thought.

-Cory

--

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

wrote:
John Theune wrote:
: I'd really like to see some number to support your conclusion. By my
: estimates 100 hrs * 11 gals per hour = 1100 gal per year. RG decreases
: fuel need by 5% or 55 gal * $3.50 = 192.50 per year in fuel savings.
: From the numbers throw about by my aircraft owning buddies the delta in
: ownership costs for a retract are much more then that.

: Assumptions in above: Fuel burn is about the same for 180HP engines in
: Comanche 180 and 172s with 180HP engine. Increased speed reduces need
: for fuel by 5% by higher speed in cruise, climb fuel burn is the same.
: Big YMMV is added

Not to be too argumentative, but 5% might not be the right number. A quick
example:
http://www.risingup.com/planespecs/i...plane432.shtml
http://www.risingup.com/planespecs/i...plane427.shtml

That's a PA-28-180 vs. a PA-28-180R. Cruise of 119 kts vs. 141 kts. That's
18% improvement in speed. Others are similar around 15%. So, multiply your fuel
savings by a factor of 3 and you get $600/year. That's starting to sound more in line
with the additional costs of a gear swing every year, some more lube, and a
replacement part averaging every 5 or so.

Just food for thought.

-Cory

--

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

Very good, I was hoping somebody could come up with better numbers then
I had. It looks like from your numbers the fuel savings come close to
the extra maintenance costs so the insurance costs would swing the
balance toward the FG model cost wise. I think the extra "sex appeal"
of the RG might swing it back toward the RG side, but bottom line you
can't argue for the RG just on cost savings over FG.

Very good, I was hoping somebody could come up with better numbers then I
had. It looks like from your numbers the fuel savings come close to the
extra maintenance costs so the insurance costs would swing the balance
toward the FG model cost wise. I think the extra "sex appeal" of the RG
might swing it back toward the RG side, but bottom line you can't argue
for the RG just on cost savings over FG.

Sorry, I'm late to this thread, but it's an interesting point you bring up.

However, it's only applicable to what we might call "legacy aircraft" --
Pipers, Cessnas, Beechcraft, Navions, etc. All of the "modern" aircraft
(Cirrus, Lancair, Diamond) are going with stiff legs, and don't appear to be
paying much of a price penalty for doing so.

Anyone care to venture a guess as to how much faster an SR-22 (for example)
would go with retractable gear?
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

wrote:

: That's a PA-28-180 vs. a PA-28-180R. Cruise of 119 kts vs. 141 kts. That's
: 18% improvement in speed. Others are similar around 15%. So, multiply your fuel

Having flown many hours in both, the Arrow numbers are a bit high. Figure
135 kts for the Arrow, and you get ~15% like the others. The 200 HP Arrow
is quite a bit faster.
--
Aaron C.

On 8-Feb-2006, John Theune wrote:

I'd really like to see some number to support your conclusion. By my
estimates 100 hrs * 11 gals per hour = 1100 gal per year. RG decreases
fuel need by 5% or 55 gal * $3.50 = 192.50 per year in fuel savings.
From the numbers throw about by my aircraft owning buddies the delta in
ownership costs for a retract are much more then that.

Assumptions in above: Fuel burn is about the same for 180HP engines in
Comanche 180 and 172s with 180HP engine. Increased speed reduces need
for fuel by 5% by higher speed in cruise, climb fuel burn is the same.
Big YMMV is added


I said "RG compared to a FG WITH SIMILAR PERFORMANCE..." For comparison to
an Arrow or Sierra than burns about 10.5 GPH at 75%, that would be something
like a Skylane or Dakota that burns about 3 GPH more. For 100 hrs, that's
300 gallons, or well over $1000 at today's fuel prices.
Additional maintenance costs for an RG will probably run about $300/yr.
(This is based upon my experience and what my A&P told me.) Insurance
difference could be wildly variable depending upon pilot experience and IR
status, In my case, the extra premium for RG runs about $500/yr.
In other words, the cost of folding the gear is more than offset by the cost
of the fuel needed to drag it through the air.

-Elliott Drucker

wrote:
: status, In my case, the extra premium for RG runs about $500/yr.
: In other words, the cost of folding the gear is more than offset by the cost
: of the fuel needed to drag it through the air.

Ahh... but those are the *HIDDEN* costs. Fixed ones like insurance and extra
labor on the annual. The *direct* operating costs are lower. That's all I ever look
at when deciding if I'm going to go somewhere. The fixed costs all get cheaper the
more you fly.

Everyone has their own rationalization of why owning is better.

-Cory

--

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