M3TD Mapping Battery Calculator v1.2.10

Planning tool (intentionally conservative). Now includes visual compasses with arrows (unambiguous FROM/TO) and optional Open-Meteo wind autofill.

Inputs

Includes transit + lawnmower + turns + landing.
If set, you’ll also see predicted landing %.
Weather (Open-Meteo wind autofill)
Enter lat/lon (or pass ?lat=…&lon=… in the URL) then click to autofill wind.

Wind

Arrow shows direction wind blows (TO)

FROM W → TO E Manual
Click the compass to set WIND FROM direction.

Dock → Scan

Arrow shows outbound direction (TO)

DOCK → SCAN: N
Click the compass to set outbound heading.

Lawnmower Legs

Arrow shows primary scan-leg direction (TO)

SCAN LEGS: N
Click the compass to set scan-leg direction.
Model details (constants + math)
Baseline burn B = 2.9 %/min.
BaseUsed = T * B.

Wind bracket → Wmax (max extra burn fraction):
0–5: 0.03, 6–10: 0.08, 11–15: 0.14, 16–20: 0.22, 21–25: 0.32

Direction factor F based on Δ angle between wind direction (FROM) and travel heading (TO):
headwind: 1.00, quartering headwind: 0.70, crosswind: 0.35, quartering tailwind: 0.20, tailwind: 0.10

Transit factor = average of outbound + inbound F.
Scan factor = average of down-leg + up-leg F.

Distance bracket weights (wind sensitivity):
Short: P_transit 0.12 / P_scan 0.88
Medium: P_transit 0.20 / P_scan 0.80
Long: P_transit 0.28 / P_scan 0.72

F_total = P_transit*F_transit + P_scan*F_scan
Penalty = Wmax * F_total
Used = BaseUsed * (1 + Penalty)
MinTakeoff(30) = Used + 30, MinTakeoff(20) = Used + 20

Results

Estimated battery used (%)

—

—

Minimum takeoff % to land with 30%

—

—

Minimum takeoff % to land with 20%

—

—