Cost of ownership question

In defense of 6 cylinders, many are older low compression ones like mine
which means one can burn auto fuel. Asuming one has an airport with
auto fuel available the cost difference is about $1/gallon which at 9g/h
leads to a savings of $16,200 over an 1800h TBO period. This pays for
the cost of the overhaul.

Helen

On 29-Dec-2004, Helen Woods wrote:

In defense of 6 cylinders, many are older low compression ones like mine
which means one can burn auto fuel. Asuming one has an airport with
auto fuel available the cost difference is about $1/gallon which at 9g/h
leads to a savings of $16,200 over an 1800h TBO period. This pays for
the cost of the overhaul.

But then again, most 6 cyl engines (with the exception of the old Cont.
O-300) burn a lot more than 9 gph at typical cruise settings. Also, most
low compression engines are carbureted, with lower efficiency than injected
engines of similar power. For example, hourly fuel burn of a Lyc. O-360
(180 hp carbureted) is very close to that of their IO-360 (200 hp injected)
at equal percentage power settings.

Helen's main point is a good one, though. With fuel prices soaring,
efficiency, or possibly the ability to use cheaper autogas, is a big issue
for total operating cost. This is particularly true for well-utilized
airplanes where fixed costs (insurance, hangar/tiedown rental, etc) are a
smaller fraction of total cost.

Another factor in relative efficiency is retractable vs fixed gear. A 200
hp 4-place retractable will have about the same speed as a 240 hp 4-place
fixed gear plane. Think Arrow vs Dakota or Cardinal RG vs C-182. In
cruise, the RG will probably burn about 3 gph less than the FG. At 150
hours/year and $3.00/gal, that's $1,350/year. Much, much more than the
extra cost of maintenance likely required for the RG and possibly slightly
higher insurance premiums. So you end up saving money with the RG, as long
as you remember to lower the gear for landing!

--
-Elliott Drucker

wrote in message
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On 29-Dec-2004, Helen Woods wrote:

Another factor in relative efficiency is retractable vs fixed gear. A 200
hp 4-place retractable will have about the same speed as a 240 hp 4-place
fixed gear plane. Think Arrow vs Dakota or Cardinal RG vs C-182. In
cruise, the RG will probably burn about 3 gph less than the FG. At 150
hours/year and $3.00/gal, that's $1,350/year. Much, much more than the
extra cost of maintenance likely required for the RG and possibly slightly
higher insurance premiums. So you end up saving money with the RG, as
long
as you remember to lower the gear for landing!

All true, but when it comes to hauling a load, there's no substitute for
horsepower. A Dakota or 182 are fill-the-seats-and-tanks airplanes, which
the Arrow and Cardinal RG are certainly not.

-cwk.

On 29-Dec-2004, "C Kingsbury" wrote:

All true, but when it comes to hauling a load, there's no substitute for
horsepower. A Dakota or 182 are fill-the-seats-and-tanks airplanes, which
the Arrow and Cardinal RG are certainly not.

True to an extent. But, when fueled for a given mission the difference in
payload is not quite as big because of the much larger fuel load required
for the thirstier big engine. However, your point is valid in that someone
needing a load hauler will generally be looking for a plane with a bigger
engine. (The Dakota is particularly adept in this regard.) If efficiency
and range are primary considerations (with comfort, cabin size, and
performance being equal) it's hard to beat a later model Arrow.

--
-Elliott Drucker

C Kingsbury wrote:
wrote in message
news:3aJAd.24094$h.20346@trnddc04...

On 29-Dec-2004, Helen Woods wrote:

Another factor in relative efficiency is retractable vs fixed gear. A 200
hp 4-place retractable will have about the same speed as a 240 hp 4-place
fixed gear plane. Think Arrow vs Dakota or Cardinal RG vs C-182. In
cruise, the RG will probably burn about 3 gph less than the FG. At 150
hours/year and $3.00/gal, that's $1,350/year. Much, much more than the
extra cost of maintenance likely required for the RG and possibly slightly
higher insurance premiums. So you end up saving money with the RG, as

long

as you remember to lower the gear for landing!


All true, but when it comes to hauling a load, there's no substitute for
horsepower. A Dakota or 182 are fill-the-seats-and-tanks airplanes, which
the Arrow and Cardinal RG are certainly not.

Actually, the Arrow I now fly in a club has a greater full fuel useful
load than did my 182. Now its full fuel is 50 gallons rather than 84
(or was it 88, I forgot for the 182 with LR tanks), but it still carries
a surprising amount. The downside is that the 180 HP is really
noticeable at gross weight. It climbs about like a C-150. I really
miss the 182 on TO and climb. The Arrow is marginally faster in cruise,
but not by much. The win is that it burns about 9 GPH at 125 knots
rather than 12.


Matt

On 30-Dec-2004, Matt Whiting wrote:

Actually, the Arrow I now fly in a club has a greater full fuel useful
load than did my 182. Now its full fuel is 50 gallons rather than 84
(or was it 88, I forgot for the 182 with LR tanks), but it still carries
a surprising amount. The downside is that the 180 HP is really
noticeable at gross weight. It climbs about like a C-150. I really
miss the 182 on TO and climb. The Arrow is marginally faster in cruise,
but not by much. The win is that it burns about 9 GPH at 125 knots
rather than 12.


My Arrow IV has a useful load of 980 lbs. With full tanks (72 gal usable)
VFR range (1 hr reserve) is about 900 nm. With fuel limited to 50 gal
usable payload is a solid 680 lbs. I get 135 kts on 9.4 gph at 65% cruise
(at 9000 ft.) There is a big efficiency difference between the 200 hp and
180 hp engines.

--
-Elliott Drucker