Grams per Watt: Why Multirotor Motor Buyers Stopped Shopping on Peak Efficiency

A new market analysis puts global multirotor motor revenue growth at 7.9% a year through 2032 — and quietly confirms that the number buyers argue over has shifted from peak efficiency to power per gram.

A Growth Number That Hides a Shift

The headline figure is easy to skim past. According to QYResearch data cited by 168 Report, the global multirotor drone motor market was worth USD 1.736 billion in 2025, roughly USD 1.868 billion in 2026, and is projected to reach USD 2.945 billion by 2032 — a 7.9% compound annual growth rate.

Set that next to the rest of the power system and the gap becomes the story. The wider drone motor market is growing at 16-17%, and multirotor propulsion systems including ESCs and propellers at around 14%. The motor is the most standardized link in the chain, the number of motors per airframe has stopped rising, and growth now comes from replacing small motors with larger ones. A 7.9% rate is not weak demand. It is value migrating from unit count to watts per aircraft.

Two Buyers, Two Very Different Motors

Agricultural spraying is the most predictable end of the market. China's plant-protection drone fleet reached 309,000 units in 2025 and covered 3.04 billion mu-treatments — the largest fleet and sprayed area in the world — and the analysis attributes that growth to labour substitution rather than subsidy. What this buyer needs is unglamorous: dust sealing, demagnetization margin across a wide temperature range, and long intervals between teardowns.

Industrial inspection splits in the opposite direction. Power-line patrol wants low rpm and high torque to hold a long hover; oil and gas adds explosion-proofing and electromagnetic-interference constraints; compound-wing and multirotor hybrids are pulling axial-flux motors and 400-800V systems into the conversation. Same airframe class, a completely different duty cycle.

The Barrier Moved Upstream

Brushless DC remains the mainstream architecture, but the benchmark has shifted from steady-state efficiency to power density coupled with thermal management. Two published data points frame the new bar: ePropelled's Sparrow APM30 Kv300 delivers more than 380 W continuous from 125 g, and Reflex Drive's FOC ESC, built on Infineon OptiMOS power devices, pushes 3.8 kW continuous out of 180 g and 120 cubic centimetres for 15-20 kg thrust platforms.

Read the second number as a system figure, not a component one. Pushing that much power through that little silicon and copper only works if the drive knows the motor's inductance and the propeller's load curve. That is why the competitive barrier has moved from winding technique and magnetic circuit design to power semiconductor selection and drive-algorithm co-design — and why suppliers who cannot optimize motor and ESC together will struggle in the mid and heavy industrial classes.

What to Ask Before You Lock an Arm Spec

For anyone specifying a propulsion arm this quarter, the practical questions have changed:

Ask for continuous watts at your actual hover point, with your propeller, at your field ambient temperature — not a peak number taken on a bench at 25 degrees. Ask for winding temperature headroom at 45 degrees and above. Ask who tuned the ESC, and whether motor, drive and propeller were characterized as one set. Ask the maintenance interval in hours, and which parts are field-replaceable.

The structure of the market makes this more important, not less. In civil drone propulsion systems excluding batteries, DJI held 43.2% in 2024 and T-MOTOR 7.1% — a reminder that integrators keep motor design in-house. Third-party suppliers earn their place where a specific duty cycle, a specific voltage or a specific mounting pattern has to be met: the matched arm, not the loose motor.

Source: Eastmoney Caifuhao (citing QYResearch via 168 Report) — original report. This article is Aerotora's independent analysis, written for drone fleet operators and component buyers.