Sprayer Calibration Calculator & Spray Drone Coverage

For a fixed hydraulic orifice and unchanged liquid, $q=q_0\sqrt{p/p_0}$ and total flow $Q=nq$. Colorado State Extension gives the equivalent squared-flow pressure adjustment. The illustrative reference flow is TeeJet Catalog 51A metric, printed p. 12: XR11004 at 3 bar, 1.58 L/min; the published XR operating range is 1–4 bar. These are editable example values.

Application rate is $R=Q/(vW)$ after converting covered area to hectares. For ground broadcast booms, $W=ns$; drones use tested effective swath. The target total flow is $Q_t=R_t vW$, required hydraulic pressure is $p_t=p_0(q_t/q_0)^2$, and speed at fixed flow is $v_t=vR/R_t$. Montana Extension and Purdue PPP-154 give independently published US-unit examples of this same area balance.

The rectangular route has $N=\lceil B/W\rceil$ straight passes, distance $NL$ and $N-1$ turns. Full flow applies only on straight passes: solution allowance $V=Qt_s$. The difference from $RA$ is the final-width allowance, not a prediction of deposited dose. Nominal tank area is $V_{tank}/R$.

The Drone Flight Time calculator's energy balance is reused: $t_b=E_{rated}u/P_{loaded}$. Here power is a measured mission average, not a rotor model. Available in-field battery time subtracts return/transit allowance. With field-average spray fraction $f_s=t_s/t_w$, tank-limited working time is $V_{tank}/(Qf_s)$. Departures round $t_w$ divided by the shorter tank/battery interval upward. Job time adds transit for every drone departure and combined service at all but the first departure; effective capacity is field area divided by job time.

• Identical hydraulic nozzles, clean water or a similar Newtonian liquid, constant nozzle pressure and speed. No density/viscosity correction, wear correction, hose-pressure calculation or droplet-size prediction.
• Measured-flow mode uses total outlet flow directly; its hydraulic target pressure is absent. The hydraulic reference curve remains an illustration of the reference nozzle, not a rotary-atomizer or rate-controller model.
• Level rectangular field; no obstacles, exclusion zones or headland spray. The last pass is shifted inside the field when needed. The model charges a full-flow last pass and does not establish edge deposition or uniformity.
• The entire lane change is represented by the entered turn time, including its translation. The route is schematic and has no turn radius or waypoint export.
• Constant representative loaded-flight power; reserve/losses are included once in the usable energy or entered endurance. No recovery of energy as the tank empties.
• Drone stops combine a top-up and fresh-battery swap, even if only one resource limits the departure. Tank-equivalent loads are a liquid-only minimum, while planned departures can be higher. Battery swaps exclude the initial fitted pack.
• Average-cycle logistics distribute turns uniformly. Exact resource events can shift a departure count near a boundary; verify with flight logs and leave operating margin. Service includes all turnaround work between departures, but no initial preparation, final cleanup, charging queues or weather delays.

For preliminary calibration and rectangular-field logistics, not product selection, chemical mixing instructions or autonomous flight control. Broadcast ground booms only; banded spraying, airblast sprayers and row-specific nozzle layouts need different width definitions. Use measured flow for non-hydraulic, PWM or rate-controlled outlets. Change reference flow, reference pressure and permitted pressure bounds together when changing nozzle type.

Swath must be established at the intended height, speed, liquid, canopy and weather; the calculator cannot infer it from altitude or spray angle. The field width must be at least one effective swath. The schematic supports up to 500 passes; split wider jobs into blocks. Use Result units for metric or US customary result cards (US gallons). For inputs, choose an available unit or type a unit explicitly, such as 2 gal/acre, 0.4 gal/min, 40 psi or 10 gal. This converts the entry into its displayed field unit. Charts and detail tables retain their explicitly stated units.

Battery energy/power is an estimate of usable endurance, not a flight-safety margin or a manufacturer guarantee. Counted swaps assume a charged replacement pack at every planned drone departure. Check aircraft payload, battery health, pump capacity, real refill/return times and charging supply separately.

Legal scope: EU Directive 2009/128/EC, Article 9, consolidated text of 26 July 2019, checked 29 October 2026. Its prohibition has limited derogations subject to competent-authority approval; check current law, national implementation and product/aviation requirements in force.

This planning tool grants no authorization for aerial spraying (legal note checked 29 October 2026).