Under Part 107, the maximum takeoff weight of a small UAS (including payload) must be less than:
Why →
Under 14 CFR § 107.1, a small unmanned aircraft is defined as one weighing less than 55 pounds (approximately 25 kg) on takeoff including everything on board. This is the definitional weight limit. Aircraft at or above 55 lbs require different regulatory treatment.The trap →
50 pounds and 25 kilograms (55 lbs) are close but wrong. The regulatory threshold is specifically "less than 55 pounds", not "55 pounds or less." An aircraft weighing exactly 55.0 lbs is NOT a small UAS under Part 107.SOURCE → 14 CFR § 107.1(b)(1)CHECKED APR 21ACS IV.A.K2EASY