Prop Speed / Mach / Power Lab

Explore how diameter, pitch, rpm, voltage, CdA, mass, motor limits, and battery size interact. The real-build estimates use sea-level drag power and loaded_rpm ≈ 0.7 · Kv · V.

Interactive Prop Lab (single operating point)

Real build inputs

Mass is derived from airframe, battery, and motor masses. CdA rows use drag power for cruise and top-speed estimates.

All-up mass

562 g

220 airframe + 210 battery + 4× 33 motor

Pitch vs rpm

rpm required from pitch: 32808.5

chosen rpm: 40,000

Mach vs rpm

max rpm (M_adv ≤ 0.9): 40636.0

tip Mach: 0.9

advancing Mach: 0.9

Prop absorption model

Kv needed: 2597 rpm/V

Absorbed prop power: 1.42 kW

Feasible? Yes

Mass & endurance sanity

Static thrust (4× props): 169.4 N

Thrust-to-weight: 30.73 ×

Absorption-model endurance: 1.2 min

Absorption-model range: 6.0 km

Vehicle drag model by CdA

CdADrag powerPower marginMax speedLimiterEnduranceRangeRun energyRunsAfter planned
0.00301.64 kW+1.76 kW364 km/hMach limit1.0 min5.2 km9.3 Wh3.10.6 Wh / 0.0 min
0.00603.27 kW+0.13 kW302 km/hdrag power0.5 min2.6 km10.1 Wh2.80.0 Wh / 0.0 min
0.01005.45 kW-2.05 kW256 km/hdrag power0.3 min1.6 km10.0 Wh2.90.0 Wh / 0.0 min
0.01508.18 kW-4.78 kW222 km/hdrag power0.2 min1.0 km9.7 Wh3.00.0 Wh / 0.0 min

One max-speed run assumes acceleration from rest plus 10s held at estimated max speed. Mass affects top speed through thrust-to-weight here; power-limited top speed is mostly CdA and motor power.

rpm vs pitch (200–800 km/h)