RC Flight Session Cost Calculator

Nobody discovers what this costs from the receipts, because the receipts are for packs and props and a tank of fuel to get to the field, and none of them are per flight. The expensive part is usually the one that never appears as a purchase: a pack quietly spending a fraction of its life every time it is charged. This divides the whole lot across the flights you actually get and prints the number per minute in the air, which is the only figure that compares to anything.

What you paid, including whatever the shipping worked out at.
Your own figure, from your own log or from what the pack maker states for that pack. It moves with how hard you discharge and how warm the pack runs.
One pack cycle per flight. The RC battery rotation calculator works out how many a session really holds.
Cells in series times the nominal volts per cell on the pack label.
From your own bill, all-in, including the standing charges spread over your usage.
Count the sets you actually bin, including the ones binned after a knock rather than from wear.
What you set aside per outing towards the machine, the transmitter, the goggles and the repairs. Take last year total and divide by the sessions you flew.
Fuel, tyres and wear, from your own running costs.
Whatever you actually pay in a year to be allowed to do this, from your own paperwork.
Coffee, a field fee, memory cards, tape.
RC Flight Cost Calculator — Cost per Pack and MinuteBuildFigure

The pack is the expensive part and it never sends an invoice

A 52 dollar pack that gives 150 usable cycles costs 35 cents every time it is charged. The electricity to fill it — five amp hours at 22.2 volts, three quarters of it replaced, through a charger that is 85 percent efficient, at 17 cents a kilowatt hour — costs 2 cents. Pack wear is roughly seventeen times the power bill, and it is invisible because it arrives as a purchase eighteen months later rather than as a cost per flight.

That ratio explains a great deal of behaviour at a flying field. People who fly a lot care about how deep they discharge and what voltage a pack sits at between sessions, and are entirely relaxed about leaving the charger running. Both positions are correct and the arithmetic above is why.

Fixed cost is what makes short outings expensive

At the defaults, eleven flights cost 4.62 dollars in consumables and 22.87 in fixed cost — the drive, a share of the annual dues, and the fund you put aside for the machine. Fly eleven times and it works out at 2.50 a flight. Drive the same 24 miles, fly three times because the wind got up, and it is 7.86 a flight for identical flying.

This is the case for fewer, longer sessions rather than more, shorter ones, and it is the reason a field ten minutes away is worth more than it looks. It is also why the page prints the fixed block separately instead of burying it in an average.

Per minute is the only comparable number

Cost per flight compares nothing, because a flight is not a unit of anything — it is however long that particular machine stays up. The defaults give 27.5 cents a minute, or 16.50 dollars an hour of airtime. That figure survives a change of aircraft, and it is the one to hold against what a job pays.

Run it for a machine with a five-minute endurance and the same consumables and the per-minute figure nearly doubles while the per-flight figure barely moves. Nothing about the flying changed. The unit did.

What is not in here

Your own time, for one, which for anyone flying commercially is usually larger than everything on this page put together. Crashes, for another: the gear fund field is meant to absorb them, but a fund sized on a quiet year is not sized for the year you put a machine into a tree. Processing time, storage, software subscriptions and insurance excess are not here either. And no figure on this page is a tax position — that is a question for whoever does your books.

Questions people ask

What does one LiPo cycle actually cost?

Pack price divided by the cycles you get from it, plus the electricity to fill it. At 52 dollars over 150 cycles that is 35 cents of pack wear against about 2 cents of power — so 37 cents a cycle, of which the power is 5 percent. The cycle life is the number doing the work, and it is the one nobody has measured. Halve it and the cost per flight nearly doubles.

How much does an hour of drone flying cost?

At the defaults on this page, 16.50 dollars an hour of airtime, all in — pack wear, power, props, the drive, dues and a fund for the machine. That figure excludes your time entirely, which for paid work is normally the biggest line of all. Change the flights per session and it moves sharply, because most of the fixed cost lands whether you fly once or a dozen times.

Why is the cost per flight higher when I fly less?

Because the drive, the annual dues and the gear fund are spent the moment you turn up. At the defaults those come to 22.87 dollars a session. Split across eleven flights that is 2.08 each; across three it is 7.62 each, for exactly the same flying. Consumables per flight never change — everything else does.

What cycle life should I put in for my packs?

Whatever you actually get, or whatever the maker of that specific pack states. This page will not offer a figure. Cycle life moves with how deep you discharge, how warm the pack runs, what current you pull and what voltage it sits at between sessions, so a number from someone else flying differently is not yours. If you have no idea, put in what you have seen from the last pack you retired.

Does this include repairs and crashes?

Only through the airframe and radio fund, which is a figure you set. Take what you actually spent last year on the machine, the transmitter, spares and repairs, divide by the sessions you flew, and put that in. A fund sized on a year with no incidents is not sized for a year with one, and this page has no way to know which kind of year you are having.

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