Aero tow cost estimation

On Monday, July 14, 2014 11:00:13 PM UTC-6, Morgan wrote:
Hi Bill,



Took me a little while to get back to this, but I've got two spreadsheets to share with you.



One is a pretty generic airplane cost that you'll probably look at and feel familiar with. It's one I got from someone, cleaned up and added a few formulas in order to make changing variables cleaner and easier when trying to assess costs.



The second is pretty old. How old? Well, Avgas was $4.10gal last time I updated it. It was $5.85 here when I fueled on Sunday.



In any event, it's not terribly pretty, but allows you to assess the cost across the number of tows each year. That one is the GenericTowplaneCost.xls file.



Between the two you can probably work out a reasonable cost structure to anticipate for providing tows. Our towplane has been great for our club, despite an early rebuild and some unexpected damage pulling it from the hangar one day. I think we've been turning close to $20,000 in tow revenue annually as of late and that is at relatively low tow rates thanks to volunteer tow pilots.



Towplane Operational Costs:

https://dl.dropboxusercontent.com/u/...tEstimate.xlsx



Tow Costs vs Revenue

https://dl.dropboxusercontent.com/u/...cTowCosts.xlsx



For what it is worth we are operating a Cessna 150/150 at an 800MSL private airport. 3000ft runway and 100+ temps in the summer time. We try not to take high tows in the heat of the day, but generally they aren't required and once you find a good thermal you can climb better off tow.



Hope this is helpful. You can look me up on the member locator if you want to hit me up directly about anything.



Morgan









On Monday, July 14, 2014 12:05:42 PM UTC-7, Bill D wrote:

Morgan, it's true - large, unexpected costs are a normal part of the airplane ownership experience. Having owned all or part of several airplanes, I managed to get buy by adding 35% to the expected costs to cover unbudgeted liabilities. Sometimes there was an annual surplus, sometimes a deficit but it seemed to average out. But then, maybe I was lucky.







Could you upload your spreadsheet to a public DropBox folder and let us have the link. I kinda hate to put an e-mail address on RAS.











On Monday, July 14, 2014 11:13:00 AM UTC-6, Morgan wrote:



Bill,















I think I have what you are basically looking for. You'll have to adjust the variables for your scenario, but I did this breakdown years ago.















What has continually been a factor outside the ability to capture in a spreadsheet are the unexpected costs. The engine that hadn't been run routinely for the last 10 years or whatever prior to our acquisition and subsequent internal corrosion that resulted in a rebuild at 1200hrs instead of 2000.















Or the "oops" hangar rash that adds $2000 to your costs by surprise. The general stuff is pretty easy to calculate and pad for based on hours or tows.















Morgan































On Sunday, July 13, 2014 12:04:37 PM UTC-7, Bill D wrote:







On Sunday, July 13, 2014 11:05:38 AM UTC-6, noel.wade wrote:















On Tuesday, July 8, 2014 12:49:40 PM UTC-7, Bill D wrote:































I was hoping to find a spreadsheet where I could plug in variables like TBO, overhaul cost, fuel consumption, fuel price etc... Failing that, a workup for one tug might provide a methodology from which I could create my own spreadsheet.































































































Bill - I'm not trying to be obtuse; but it really does depend on a LOT of factors. Here are a few of the major factors:































1) The operational environment (club vs commercial, for example)































2) How you use the ship (regular tows? lots of high tows? double-tows? new towpilot checkout?)































3) Runway surface and condition (smooth grass, rough grass, compact dirt, asphalt, ??)































4) What kind of ship you use (Pawnee? SuperCub? Cherokee or C-182?)































5) How many tows per year you expect to do































6) How many total towplanes will you be operating































7) Local weather (goes to your hangar/storage requirements and how many months out of the year you can use the airplane)?































8) Financial "style" of your business/club (do you require a funded reserve account so that you can pay cash for maintenance and repairs when items hit their expected life-limit; or is using credit or loans - either commercial or private - an option)?































9) Commercial use of your equipment - Are you offering a lot of commercial glider rides, or flight instruction, or other use that requires you to pay taxes and/or perform more-frequent inspections on your towplane?































































These items need to be decided/outlined before any accurate numbers can be factored - otherwise you're just firing blind.































































Take care,































































--Noel































Noel, you are not being obtuse at all - your points are excellent. I agree, there are a lOT of variables. To be clear, I'm not looking for actual costs because, as you say, they vary a lot from site to site for a lot of reasons.































I was just hoping someone had put all (or most) of those variables into a really big spreadsheet so different tug operations could plug in their particulars to more easily understand and budget their tug costs.

Thank you very much

On Monday, July 14, 2014 11:00:13 PM UTC-6, Morgan wrote:
Hi Bill,



Took me a little while to get back to this, but I've got two spreadsheets to share with you.



One is a pretty generic airplane cost that you'll probably look at and feel familiar with. It's one I got from someone, cleaned up and added a few formulas in order to make changing variables cleaner and easier when trying to assess costs.



The second is pretty old. How old? Well, Avgas was $4.10gal last time I updated it. It was $5.85 here when I fueled on Sunday.



In any event, it's not terribly pretty, but allows you to assess the cost across the number of tows each year. That one is the GenericTowplaneCost.xls file.



Between the two you can probably work out a reasonable cost structure to anticipate for providing tows. Our towplane has been great for our club, despite an early rebuild and some unexpected damage pulling it from the hangar one day. I think we've been turning close to $20,000 in tow revenue annually as of late and that is at relatively low tow rates thanks to volunteer tow pilots.



Towplane Operational Costs:

https://dl.dropboxusercontent.com/u/...tEstimate.xlsx

Morgan,

Looks like a reasonable spreadsheet. Not sure about recent years, but our Pawnee D (with 250hp STC) does about 300 hours annually, thus the cost is nearer $165/hour I believe. That includes engine reserve at $14.50/hour and compensation for tow pilots, $50/day plus $1.50 per tow, and $5 revenue. From that we set tow rates based on, IIRC, 5.5 2000ft tows per tach hour. Easily included in the spreadsheet. My numbers are mostly historical as I haven't looked at this recently. It's possible to run the O-540 well past 2000TBO, including a top end only about 3000. But that strategy doesn't always work and it's nice to have $erviceable core$.

Tow planes operating in the high country don't make full power and the fuel 'cools' the temp somewhat. Not uncommon to go way beyond the TBO, but risky over 4000 hours with the O-540.

Nearer sea level, cracked jugs are more common due to higher power and more thermal shocking. Thus the engine reserve rate needs to be higher.

YMMV,

Frank Whiteley