Why calibrate
Nobody sets out to miss.
A nozzle wears. A boom bends a little. Pressure wanders off the number you set. From the seat, every pass looks the same as the last one — and the field tells you otherwise three weeks later.
Misapplication is rarely carelessness. It is an unmeasured pattern. That part is fixable.
01
Same aircraft. Same spacing. A different field.
No pass puts a full rate on its own edges. The outer part of every swath is thin on its own, and it only comes up to rate when the next pass lands on top of it. That overlap is the whole game — and whether it works depends on a pattern you have never seen.
Watch each pass land: the strip beside it goes from thin yellow to on-rate green as the new pass tops it up. Then drag the spacing tighter — more passes, more overlap — and see the bare strips close. Reading a line of cards tells you where that point is before the crop does.
8 passes to cover the field
Deposit vs target (shaded = ±20%)
- Unsprayed
- Under-applied
- On rate
- Over-applied
CVVariation (CV)
21%
Under-applied
25%
Over-applied
25%
Streaks you would see from the road in a few weeks.
Illustration of the idea, not measured data: two stylized pass shapes, flown at the spacing you choose. No pass puts a full rate on its own edges — the field only comes up to rate where the next pass lands on the last one. Your own numbers come from reading your own cards.
Volume in fine droplets (under 100 µm)
4.4%
Landing past the field edge
…
Illustration of the idea, not a drift model: each dot is an equal share of spray volume, released ten feet up with a typical droplet spread. Wind is scaled down to roughly what it is at working height. It ignores evaporation, boom position, turbulence and temperature inversions — all of which move real drift. Always follow the label.
02
Every spray has a fine tail. It travels.
A droplet half the size falls far slower, so it spends far longer in the wind. Nudge the droplet size and the wind and watch where the volume ends up.
You cannot see a spectrum from the cab. A card shows it — and what moves it is in your hands: nozzle, pressure, speed, a drift-reduction agent.
03
Good is a starting point. Better is a habit.
The best applicators are not the ones who never had a bad pattern. They are the ones who went and looked, changed one thing, and measured again.
- First card line31%
- Tighter swath22%
- Droplet size adjusted15%
- Truth Test: speed11%
- Truth Test: DRA9%
Measure
A card line across the swath tells you what the aircraft really does — not what it did when it was new.
Change one thing
Spacing, speed, pressure, droplet size, mix. Change one variable and the result means something.
Keep the record
A report you can hold up next season, and hand to a customer or a neighbor who asks.
Better stewards
Put it where it belongs. Then prove it.
Neighbors, customers and regulators all ask the same quiet question: how do you know? A measured pattern is the answer you can hand them. Aerial Cal reads the cards, keeps the record, and shows whether this season is better than the last.
The pictures on this page are illustrations of the idea, not predictions. Real drift and real patterns depend on your aircraft, boom, nozzles, weather and more, and the label always governs. Aerial Cal gives you estimates to inform your judgment; you remain responsible for the application.