1. Real coverage, not spec-sheet coverage
Swath times speed gives acres per minute; the coverage efficiency removes turns and overlap. The pump caps the speed, because gallons per minute is the rate times acres per minute. A sortie then ends at the smaller of the tank and the battery, and the crew refills and swaps before the next one, waiting for a charged battery if there are too few sets.
2. The worked field
| Step | Example |
|---|---|
| Spray-only coverage (acres per hour) | 37.1 |
| Sorties (tank-limited) | 16 |
| Minutes from first takeoff to last landing | 204 |
| Crew hours incl. setup and driving | 4.05 |
| Drone wear | $28.04 |
| Battery wear | $14.93 |
| Crew labor | $226.87 |
| Truck | $14.00 |
| Share of yearly fixed cost | $120.00 |
| Total cost | $403.85 |
| Cost per acre | $5.05 |
| Price per acre for a 30% margin | $7.21 |
The recommended price per acre is the cost per acre divided by 0.70 for a 30% margin. A tiny field costs almost as much to reach as a big one, which is why a minimum charge per field matters. Run it with your own drone and fields.
Common questions
What is a fair price per acre for drone spraying?
There is no single fair price: it depends on your cost per acre and the margin you need. Work out drone wear, battery wear, crew time, driving and your share of fixed costs for a typical field, then divide the cost per acre by one minus your target margin. Check the result against what local custom applicators charge, and against your minimum charge for small fields.
Why is my real acres per hour lower than the spec sheet?
The spec sheet gives spray-only coverage at full speed. Real jobs add turns and overlap, pump limits when you spray at a high rate, refill and battery swaps between sorties, charging waits when you have few battery sets, setup at the field and driving to it.
How many battery sets do I need?
Enough that a battery is charged by the time the crew has refilled the tank. If the charge time plus the flight time, divided by your number of sets, is longer than the flight plus the refill and swap, charging is slowing you down and another set will speed the job up. The calculator names which one applies.