What is the maximum takeoff weight limit for a small UAS under FAA Part 107?

Under 14 CFR Part 107, a small unmanned aircraft system must weigh less than 55 pounds at the time of takeoff, including the aircraft itself, any payload, batteries, and all other onboard equipment. This 55-pound limit is a strict regulatory ceiling — an aircraft weighing exactly 55 pounds or more does not qualify as a small UAS under Part 107. Operations with aircraft at or above that weight require a different regulatory authorization or an FAA waiver.

How do you calculate the takeoff weight of a drone to make sure it complies with Part 107?

To determine Part 107 compliance, you must add together the weight of the bare aircraft, installed batteries, any attached payload such as cameras or sensors, and any other equipment affixed to the aircraft at the moment of takeoff. Nothing onboard at launch can be excluded from the calculation. The FAA's Remote Pilot — Small Unmanned Aircraft Systems Airman Certification Standards emphasize that remote pilots must understand loading and weight limits as part of sUAS performance planning.

What's the difference between an sUAS and a model aircraft under FAA rules, and does the 55-pound limit apply to both?

A small UAS operated under 14 CFR Part 107 is used for non-recreational purposes such as commercial photography or inspection, while model aircraft are flown purely for hobby or recreational purposes under the Special Rule for Model Aircraft codified in 49 U.S.C. 44809. The 55-pound weight threshold originated in FAA rulemaking and applies specifically to the definition of a 'small unmanned aircraft' under Part 107; recreational flyers operating heavier aircraft must notify the FAA and may face additional requirements. Both categories require FAA aircraft registration if the aircraft weighs more than 0.55 pounds (250 grams) at takeoff.

Maximum Takeoff Weight and FAA Part 107 sUAS Weight Limits

When the FAA wrote Part 107 — the rule that governs most commercial and recreational small unmanned aircraft system (sUAS) operations in the United States — it drew a hard line at 55 pounds. Cross that line, and you are no longer flying under Part 107 at all. The weight rule seems simple on its surface, but once you start stacking up batteries, cameras, payload pods, and tethers, it becomes surprisingly easy to approach or exceed the limit without realizing it. This article breaks down exactly how the FAA defines maximum takeoff weight (MTOW), what counts toward that number, why the threshold exists, and what the practical and legal consequences are for the remote pilot in command (RPIC).

Understanding sUAS weight limits is not just about passing the Part 107 aeronautical knowledge test — it is about operating lawfully every single time you power up your aircraft. The RPIC is directly responsible for ensuring the aircraft is legal before flight, which means this topic belongs in your pre-flight checklist, not just your study notes.

How the 55-Pound Limit Is Defined

Under 14 CFR Part 107.3, a small unmanned aircraft is defined as an unmanned aircraft weighing less than 55 pounds on takeoff, including everything that is on board or otherwise attached at the moment of liftoff. The regulations are explicit: the 55-pound figure is not a structural limit set by the manufacturer — it is a regulatory ceiling set by the FAA. An aircraft can be rated by its maker to carry 60 pounds, but that does not make it legal under Part 107.

The phrase including everything on board is critical. The FAA counts the following items as part of the takeoff weight:

The aircraft structure itself — airframe, motors, propellers, and fixed electronics.
All onboard batteries — including any redundant or backup power cells, regardless of whether they are actively powering the aircraft at that moment.
Cameras, gimbals, and sensors — thermal cameras, LiDAR units, multispectral sensors, and any other payload attached to the airframe.
Any cargo being transported — packages, samples, medical supplies, or any other object being carried for any purpose.
Tethers and physical connections — for tethered operations, any physically attached hardware and connections at the aircraft should be accounted for as part of the aircraft's configuration; consult current FAA guidance for how a given tethered setup is treated.
Any fuel — for gasoline-powered or hybrid sUAS, fuel loaded at takeoff counts toward the total.

Notice what is not included: the weight of the remote controller held by the pilot, the weight of a ground station, or the weight of cables that remain on the ground. The boundary is the aircraft itself at the moment wheels (or landing gear) leave the ground.

The 0.55-Pound Registration Threshold

Separate from the Part 107 operational limit is the registration threshold. Under 14 CFR Part 48, any sUAS weighing more than 0.55 pounds (250 grams) and less than 55 pounds must be registered with the FAA before it can be flown outdoors. The registration threshold and the Part 107 operational ceiling create two distinct weight-related rules that apply to sUAS:

Below 0.55 lb: No registration required (though Part 107 certification may still apply for commercial operations).
0.55 lb to just under 55 lb: Registration required; eligible for Part 107 operations.
55 lb and above: Not covered by Part 107; requires a different form of FAA authorization (typically a Part 91 operation with an airworthiness certificate or a Certificate of Waiver or Authorization).

For the knowledge test, keep both thresholds clear. Confusing 0.55 pounds with 55 pounds is one of the most common errors students make.

Why 55 Pounds? The Safety Rationale

The FAA chose 55 pounds as the upper boundary for the small UAS category after analyzing the kinetic energy an unmanned aircraft can transfer in a collision. A heavier, faster-moving aircraft poses a greater hazard to people on the ground, manned aircraft, and infrastructure. Below 55 pounds, the FAA determined that a risk-based, remote-pilot-certification approach (rather than full aircraft airworthiness certification) provided an acceptable level of safety for low-altitude, line-of-sight operations.

Above 55 pounds, the risk profile changes significantly. Larger aircraft carry more kinetic energy, can be harder to see and avoid in the National Airspace System (NAS), and may carry systems complex enough to warrant the same type-certification and airworthiness oversight applied to manned aircraft. This is why the 55-pound line exists as a gateway to a fundamentally different regulatory framework.

Practical Loading and Weight Management

The weight of a drone system is rarely a single static number. Payloads change between flights. Operators swap cameras, attach different battery configurations, or add third-party accessories. This makes weight management an active responsibility for the RPIC, not a one-time check.

Consider a professional mapping drone with the following components: airframe and motors at 18 lb, primary flight battery at 8 lb, backup battery at 4 lb, LiDAR sensor at 9 lb, and a small optical camera at 3 lb. Total: 42 lb — safely within Part 107. Now suppose the operator adds a thermal camera (4 lb) and a data-relay pod (6 lb). New total: 52 lb — still legal but with only 3 lb of margin. A second battery swap to extend flight time pushes the total over 55 lb, and the flight is now illegal under Part 107 without additional authorization.

This kind of incremental payload creep is a real-world problem. Professional operators should maintain a weight and equipment log for each aircraft configuration, calculate takeoff weight before every flight when payloads change, and build in a safety margin rather than routinely operating at the ceiling.

Key Numbers and Rules

55 lb (exactly) is not permitted — the rule says less than 55 pounds, so an aircraft weighing exactly 55.0 lb at takeoff is outside Part 107.
0.55 lb (250 g) is the registration threshold under Part 48.
Weight is measured at takeoff, not at landing. Fuel burn or battery discharge during the flight does not retroactively make a heavy takeoff legal.
The RPIC is responsible for verifying weight compliance before every flight — this cannot be delegated to a visual observer or crew member.
Aircraft exceeding 55 lb may operate in the NAS under a Part 107 exemption combined with a Certificate of Waiver or Authorization (COA), a type-certificated aircraft operated under Part 91, or an exemption under 49 U.S.C. §44807, but not under standard Part 107.
Manufacturers' published MTOW figures are a useful starting point, but the RPIC must calculate actual configured weight for non-standard payloads.

Waivers and Exceptions

Part 107 allows the FAA to grant waivers for many of its operational rules — for example, waivers for operations beyond visual line of sight or over people. Night operations no longer require a waiver: under the Part 107 amendments effective April 21, 2021 (14 CFR 107.29), an RPIC may fly at night without a waiver provided they have completed the updated recurrent training and the aircraft is equipped with anti-collision lighting visible for at least three statute miles. However, the 55-pound weight threshold is not a waivable provision under Part 107. It is a definitional boundary. An aircraft at or above 55 pounds simply falls outside the scope of Part 107 and requires a different regulatory pathway regardless of the pilot's qualifications or the safety case presented.

Operators planning to use heavy-lift systems for tasks like aerial firefighting support, precision agriculture with large spray rigs, or package delivery with heavier payloads must engage with the FAA's aircraft certification and authorization processes that apply to aircraft above the Part 107 ceiling.

Common Test Traps

Exactly 55 pounds is not legal. Part 107 requires the aircraft to weigh less than 55 pounds at takeoff. A drone weighing exactly 55.0 lb is not a small unmanned aircraft under Part 107 — a classic exam trick.
Payload is always included. Some questions describe a drone body that weighs 40 lb and ask about adding a 15-lb camera payload. Students sometimes count only the airframe weight and miss that the combined 55-lb total puts the aircraft right at — and therefore outside — the limit.
Batteries count in full. All batteries on board count toward MTOW, even spare batteries that are physically attached but not in use. Do not subtract unused battery weight.
The registration threshold is 0.55 lb, not 5.5 lb or 55 lb. Confusing 0.55 lb (250 g) with 55 lb is a frequent error on the knowledge test.
Weight is measured at takeoff, not average flight weight. Even if the aircraft burns fuel and ends the flight lighter, if it took off over the limit, the flight was illegal from the moment of liftoff.