Operating Costs

[norriscathy]

Getting very, very close to purchasing a NA 337. I've got a handle on most expenses: Fuel at 20 gph; insurance $1,000 per year (liability only, no hull); engine reman $35K; engine overhaul $25K; T-Hanger $40 per month. Just can't seem to get a handle on other operating/fixed expenses. I've numbers as high as $445 per hour! Once everything is in good shape does anyone have a good fix on 337 expenses? Doubt I'll fly more than 75-100 hours per year. Thanks for your help.

Norris

[Paul Sharp]

I find that figuring an amount equal to direct costs per hour (fuel, oil, etc.) pretty closely approximates ongoing costs for maintenance and servicing.

[edasmus]

Your fuel for a normally aspirated model is reasonable. Turbo models are probably higher but I do not operate one so I cannot speeak from experience there. Since you have your insurance and hanger fees nailed down, then the only thing left is maintenance.

It has been my experience that trying to approximate maintenance costs on 30 to 40 year old airplanes is quite challenging. I have owned airplanes for almost 20 years and I have owned my 73 C337G model for seven years and flown it about 600 hours. My least expensive annual has been $6000 and my highest (and first) has been $20,000 with the rest falling in the $8000 to $15,000 range. The airplane has been dependable during the years usually not requiring any maintenance during the time between annuals other than oil changes and the standard things one would do to keep an plane in good shape. This past year I have been struggling with a fuel guage issue that you can read all about on this site and I did have a pesky electrical problem a year or two ago that you can also read about on this site. Depending on how mechanically inclined you are and how much your IA allows your involvement in maintaining your airplane, I am certain you could safely operate with lower costs than mine. I personally am not experienced in maintenance and my shop does not allow owner participation. I enjoy my Skymaster and would encourage anyone to buy one provided they are financially prepared to operate it. It will most likely cost more than you think!

Ed Asmus

[Ernie Martin]

Norris, I noted that you just joined us. Perhaps you failed to see the second message on the Board (General Skymaster Info & Tips For Buyers). It's intended for first-time users and strongly recommends that you first do a Search on your topic before posting a question (Search is on the first blue line at the top of the screen). NOTE TO LARRY: Please, let's change the title of that message to "Tips for First-time visitors and prospective Skymaster buyers".

When you do your Search on operating costs, you will find many (perhaps a dozen or more) responses over the years, covering a broad range of users, rather than getting one or two responses. Plus, it's instant, rather than waiting a few days for people to respond.

I went and did a Search on operating costs and found lots of info. Then expanded that to annual cost and found even more stuff. Maybe engine overhaul or other terms will also yield valuable data.

Personally, I make a distinction between operating costs and overhead. The costs for tie-down/hangar, insurance, paint/upholstery and a "nothing-was-wrong" annual (maybe $1,000) are going to be there whether you use the airplane or not. I view that as overhead, not operating costs. So if a friend asks me to take him somewhere, I want to know the operating costs of that flight, namely how much that will add to my yearly costs. (I know that in Part 91 I can't charge for that, but I want to know.) Fuel costs have changed so drastically over the past year, and vary so much between location (I fly a lot to Caribbean islands, and late returns to the US sometimes forces me to land at big airports where Customs is open late and fuel is outrageously high), that I figure the operating costs as fuel + other, where "other" includes most of the annual inspection (my average costs, which you will find when you do Search, minus the $1,000 I figure if I don't use the airplane), engine/prop reserves, miscellaneous repairs through the year, oil changes, tires, batteries, etc. My "other" is now in the $80 - $90 range per hour of flight operation (not including taxiing).

Since you're new, I'll tell you I'm on my second Skymaster, I'm a mechanical engineer, and spent 10 years in the aircraft engine parts business.

On the matter of using the Search feature, please note that I'm also one of the Webmasters and I do it for your benefit.

Ernie

[norriscathy]

I did search everything I could I could find; that is were I saw the $445 per hour number. I wanted some more current "real life" numbers like the previous poster provided.

[tropical]

Originally Posted by norriscathy

I did search everything I could I could find; that is were I saw the $445 per hour number. I wanted some more current "real life" numbers like the previous poster provided.

A general rule of thumb is to take the fuel flow per hour X cost of fuel per gallon X 4.

So if your burn is 20gph and the cost of fuel is $4.00/gallon you're looking at $320 per hour. For an average C-337 I would say that's a close number.

Of course there are variables, such as condition of the plane and quality of the maintenance.

The cost to purchase is only the cost of admission to aircraft ownership. Typically the average airplane owner buys into more airplane than he can afford, dumps alot of money into it initially then begins forgoing any maintenance for the remainder of the time he owns the plane. Most new owners would rather sink high $$$$'s into gadgets and avionics rather than needed maintenance.

[gkey]

Originally Posted by norriscathy

... I've got a handle on most expenses: Fuel at 20 gph; insurance $1,000 per year (liability only, no hull); ...Norris

My two cents on 2 things you mentioned:
Fuel. Every time I refuel, I do it to the rim, and then work out my consumption based on the hours in the Journey logs. Quite consistently, my fuel burn is 17 Gal/hr. I don't fly like a speed freak, so that's what I get at 150 - 155 KIAS @ 6,000 - 8,000 AGL.

Insurance. Probably the biggest variant. I've seen cheaper ones and more elaborate ones. I am insured for motion + no motion, on ground and air , with pax and 3rd parties injury (i.e. full inclusive) for $4,700 CAD per year.