On 1 Dec 2006 19:27:17 -0800, "
wrote:

I've noticed quite a few Cessna 310s posted for sale recently on
ebaymotors and controller.com. This got me wondering if there is a
reason why there are so many on the market (beyond the obvious high
fuel and insurance costs for twins). Are 310s impacted by the spar ADs
that the bigger twin Cessnas have to deal with?

The 310 always looked like an interesting plane to me. With prices the
way they are right now, it looks like there are some bargains out
there.

Owning a high performance twin is ridiculously expensive.

Examine the 310:

Factoryengines.com lists the O-470 as ~$27k rebuilt. So $54k of
engine reserve spread across 1500 or 1700 hrs depending on the exact
engine model, and that does not include removal/installation costsl.
$31/hr reserve.

Fuel burn = 14gph * 2 = 28gph.
Gas prices are down recently, but $5 fuel was common only a few months
ago. So 28 * $5.00 = $140/hr.

Oil. $5/quart.
Consumption = 2 quart every 10 hours between the two engines = $1/hr.
Oil Changes = 20 quarts every 50 hrs = $2/hr.
Total = $3/hr.

So $140 + $31 + $3 = $174/hr for the variable costs.

Now the fixed costs:
Hangar. This one varies depending on location. A twin in heated,
shared space at my Chicago area airport is $600. A T-hangar can be
leased for $375, so let's go with that. $375 * 12 = $4,500/yr.

Insurance. I have no idea what today's rates on a 310 are, but I
looked into Seneca II insurance about 2 years ago, and the best rate
this low time ME pilot could find was $5,000/yr. I doubt a 310 is any
cheaper.

Maintenance. This is the big variable. I would think a minimum of
$7,500 should be budgeted for annuals, cylinders, avionics, and the
misc expenses.

Spread the fixed costs across 200hrs of flying. Which is probably
more than a typical owner/pilot would fly in a year.

$4500 + 5000 + 7500 = $17,000
$17,000 / 200hrs yields $85/hr.

So summing the fixed and variable costs for 200hrs per year is
~$260/hr, or $51,800 per year, and this figure neglects the cost of
capital.

The purchase price of many older 310s is not much higher than that!

Worse, there are no guarantees... ...that the engine will make TBO,
....that cracks will not be found on the 40 year old wing spar, ...
that the overwing exhaust hasn't corroded the wingspar.