Smallest/Cheapest Twin

I've owned 2, a 1966 "A" model and a 1974 "G" model. I found both to be economical to operate and never found any "maintenance nightmares". Of all the aircraft I've owned (25 so far) I found the 2 337's and the Cessna 310Q to be the least expensive to operate in terms of maintenance.

What were your annuals typically like, and what do you estimate your hourly op cost was? I don't have the numbers that I ran 4 years ago, but seem to recall (again, based on estimations provided other 337 owners) that op costs ranged from 30-40k per year for about 100-150 hrs per year. If that is incredibly off base, I would be more than happy to have my opinion reversed.
 
What were your annuals typically like, and what do you estimate your hourly op cost was? I don't have the numbers that I ran 4 years ago, but seem to recall (again, based on estimations provided other 337 owners) that op costs ranged from 30-40k per year for about 100-150 hrs per year. If that is incredibly off base, I would be more than happy to have my opinion reversed.

Since I have an A&P/IA rating my maintenance only cost me my time and parts. On my experience with the two I owned plus helping a friend maintain his "B" model then later turbo "D" I would have to say 30-40k is on the high side for an average Skymaster.

There are so many variables for any airplane under consideration. A poorly maintained Cherokee 140 could cost many times more than an average or above average model. Likewise for a (insert name here).
 
Since I have an A&P/IA rating my maintenance only cost me my time and parts. On my experience with the two I owned plus helping a friend maintain his "B" model then later turbo "D" I would have to say 30-40k is on the high side for an average Skymaster.

There are so many variables for any airplane under consideration. A poorly maintained Cherokee 140 could cost many times more than an average or above average model. Likewise for a (insert name here).

So, assuming nothing needed fixing, how many hours did it take to do the annual vs other aircraft which you are familiar?
 
Not really an adequate measure. Each type aircraft has it's own maintenance manual and it's own 100 hour/annual inspection list.

Well, I figured it would be a good start if you are paying someone else to do the work on your plane... Obviously, on the average, it takes more time to do an annual on a twin than on a single engine aircraft. There might be some twins that took less time than a particular single engine aircraft though. I would hazard to guess that the complexity of doing an annual on a C-210 and C-337 might be similar with just a bit more time added for the additional engine and differences in the tail configuration.

Having said that, a quick Google search brings up this:

http://aviationeducationintl.com/annual%20inspection.pdf

As an example of how a single engine aircraft might take more hours than a twin, you just need to compare apples to oranges like with a single engine U-2 and a twin C-337. I have no idea how long an annual inspection would take on a U-2, but I would guess that it would take longer than a C-337. Maybe some ex-AF types could share their experience...

Looks like my aircraft is one of the ones with the lowest annual inspection hours needed... That makes me feel good...
 
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Well, I figured it would be a good start if you are paying someone else to do the work on your plane... Obviously, on the average, it takes more time to do an annual on a twin than on a single engine aircraft. There might be some twins that took less time than a particular single engine aircraft though. I would hazard to guess that the complexity of doing an annual on a C-210 and C-337 might be similar with just a bit more time added for the additional engine and differences in the tail configuration.

Having said that, a quick Google search brings up this:

http://aviationeducationintl.com/annual inspection.pdf

Looks like my aircraft is one of the ones with the lowest annual inspection hours needed... That makes me feel good...

Interesting list - kind of curious why it takes 3 more hours to do an annual in a Cardinal RG vs a Lance/Saratoga? Is it the landing gear? I haven't owned a Cardinal, but have a fair amount of time in one. Didn't seem terribly complicated.

Also interesting that it takes over 10 more hours to do an annual on a 337 vs a Seneca.
 
Interesting list - kind of curious why it takes 3 more hours to do an annual in a Cardinal RG vs a Lance/Saratoga? Is it the landing gear? I haven't owned a Cardinal, but have a fair amount of time in one. Didn't seem terribly complicated.

Also interesting that it takes over 10 more hours to do an annual on a 337 vs a Seneca.

Might be the number of panels that need to be removed or number of screws. From what I've been told on my aircraft, the hours that it takes is reduced by a few if you do not have wheel pants and if you have the split nose bowl STC. Some aircraft are just a pain in the butt to work on... For example, you need to be a contortionist anorexic midget to work under the panel on my aircraft.
 
Might be the number of panels that need to be removed or number of screws. From what I've been told on my aircraft, the hours that it takes is reduced by a few if you do not have wheel pants and if you have the split nose bowl STC. Some aircraft are just a pain in the butt to work on... For example, you need to be a contortionist anorexic midget to work under the panel on my aircraft.


Possibly, although the more I look at the list, the more it appears that the Cessna landing gear is the driving factor. The fixed gear Cessnas seem to be on par with the Pipers - a 172 and a Warrior are the exact same time, but with a a 172 RG, the time goes up 5 hours whereas the Arrow is only 2 more than the Warrior. Looks like that across all RG models.
 
Hmph. I didn't see the various PA-23 versions there (Apache and Aztec). Still good info though.

Be Well,

Jimmy
 
Hmph. I didn't see the various PA-23 versions there (Apache and Aztec). Still good info though.

Be Well,

Jimmy

Strangely, lots of light twins missing from that list. Rough swag, I'd suspect that adding 8-10 hrs to the PA24 Comanche estimate is a good ball park.
 
Strangely, lots of light twins missing from that list. Rough swag, I'd suspect that adding 8-10 hrs to the PA24 Comanche estimate is a good ball park.

Maybe he's never had to do an annual on them, so he doesn't know the hours? There might be other companies with such lists on the web... I didn't really do a thorough search... I just found that within the first page of results and figured I would post it in case anyone was interested. I found the numbers a bit interesting...
 
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