Section 40102(a)(6) of Title 49 Defines an Aircraft as Any Contrivance Invented, Used, or Designed to Navigate or Fly in the Air, the Federal Aviation Administration Requires Registration of Every Unmanned Aircraft Weighing More Than 0.55 Pounds at Five Dollars Per Aircraft, the Canada Goose Weighs Up to Fourteen Pounds, More Than Twenty-Five Times the Threshold, Flies at Three Thousand Feet, Seven and a Half Times the Agency’s 400-Foot Ceiling, Has Been Reported at Twenty-Nine Thousand Feet, Eleven Thousand Feet Inside Class A Airspace, Migrates at Night With No Anti-Collision Lighting, Crosses the United States-Canada Border Twice Each Year With No Flight Plan, Radio Contact, Transponder, or ADS-B Out, Has Destroyed a Commercial Airliner With 155 Persons Aboard, Outnumbers the Agency’s 1.87 Million Registered Drones, and Has Never Once Filed a Registration

I. The Definition

The Federal Aviation Administration’s authority begins with a definition of startling breadth. Section 40102(a)(6) of Title 49 of the United States Code provides that “aircraft” means “any contrivance invented, used, or designed to navigate, or fly in, the air.” The regulation restates it more bluntly: “Aircraft means a device that is used or intended to be used for flight in the air,” under 14 CFR 1.1. The definition is functional, not mechanical. It asks one question: does it fly?¹

The agency has tested the outer boundary of this definition and reported back. In a 2012 legal interpretation, the FAA’s Assistant Chief Counsel for Regulations considered whether Yves Rossy’s jet-powered wing—a carbon-fiber wing with four turbojet engines, strapped to a man’s back, incapable of taking off on its own, steered by body movement—was an aircraft under 49 U.S.C. section 40102(a)(6). The agency concluded that the wing, “when worn and operated by a person in flight, is an aircraft.” The man wearing the wing was, for the duration of the flight, an aircraft.²

The agency’s reasoning is instructive. If a person with a wing strapped to his back is an aircraft, then the question presents itself with some force: what is a creature that comes with the wing attached?

II. The Registration Regime

The FAA maintains the most comprehensive aircraft registry in the world. Under 14 CFR Part 48, every unmanned aircraft weighing more than 0.55 pounds (250 grams) must be registered before it is flown outdoors. The registration costs five dollars, is valid for three years, and assigns a registration number that must be displayed on the exterior of the aircraft. The threshold is absolute: above 0.55 pounds, registration is mandatory; below it, the aircraft may fly under the exception for recreational flyers, and only then.³

The registered fleet is large and growing. The FAA’s aerospace forecast reported approximately 1.87 million recreational small unmanned aircraft in the system at the end of 2024, and the agency’s 2026 compendium reported that cumulative recreational operator registrations had exceeded 1.66 million by the end of December 2025. Every one of those operators paid the five dollars. Every one of those aircraft bears its number on its exterior.⁴

The regime does not stop at registration. Recreational flyers must pass the Recreational UAS Safety Test and carry proof of passage. They must operate within visual line of sight. Drones that are required to be registered must comply with Remote ID, broadcasting their identity and location at all times. The operator is, in the words of the former Transportation Secretary, an aviator, and with the title comes responsibility.³

The registry is thorough. It contains 1.87 million aircraft. It contains zero geese.

The registry contains 1.87 million aircraft. It contains zero geese.

III. The Subject

The Canada goose, Branta canadensis, is the largest of the true geese. Males weigh 5.75 to 14.25 pounds, averaging 8.5 pounds across all subspecies. The giant subspecies, B. c. maxima, produces the heaviest individuals: one exceptionally large male, rarely exceeded in the record books, weighed 10.9 kilograms, or 24 pounds, with a wingspan of seven feet four inches—the largest wild goose ever recorded of any species. The wingspan of the species ranges from 50 to 73 inches. The bird is, by any measure, heavier than air, and it is supported in flight by the dynamic reaction of the air against its wings.⁵

A male Canada goose at the top of the normal range weighs fourteen pounds. The registration threshold is 0.55 pounds. The goose exceeds the threshold by a factor of more than twenty-five. There is no provision in Part 48 for an aircraft that exceeds the threshold but declines to register. The five-dollar fee is not optional.

The fleet is large. The U.S. Geological Survey reports that Canada geese are probably more abundant now than at any time in history, with breeding populations established in every province and territory of Canada and in 49 of the 50 United States. In the 1950s, about a million called North America home; the number has since ballooned to seven million, according to estimates by the Canadian Wildlife Service.⁶

They are long-haul operators. With a favorable wind, Canada geese can cover 1,500 miles in twenty-four hours. They fly in V-formations that, according to the Audubon Encyclopedia of North American Birds, allow them to fly as much as 71 percent farther than they could individually—a formation-flying efficiency no human fleet has matched.⁷

IV. The Ceiling

Section 107.51(b) of Title 14 establishes the operating limitation for small unmanned aircraft: no higher than 400 feet above ground level. The ceiling is not advisory. Waivers are granted sparingly, and even the waiver the agency issued for high-altitude operations capped the deviation at 3,000 feet mean sea level—the altitude at which the goose considers its workday to have barely begun.⁸

Canada geese fly in V-formation at an altitude of one kilometer—3,000 feet—for migration flight. That is seven and a half times the agency’s ceiling. The maximum flight ceiling of Canada geese is unknown, but they have been reported at nine kilometers: 29,000 feet. That is seventy-two and a half times the ceiling, and it places the aircraft eleven thousand feet inside Class A airspace, which begins at Flight Level 180 and extends to Flight Level 600.⁹

Class A airspace is the most regulated airspace in the country. Under 14 CFR 91.135, operations in Class A require an IFR flight plan, two-way radio communications with air traffic control, and a transponder with altitude-reporting capability. Above Flight Level 240, distance-measuring equipment is additionally required. The goose files no IFR flight plan. It carries no radio. It carries no transponder. It carries no DME. It has been reported at 29,000 feet anyway.¹⁰

The goose flies at seven and a half times the agency’s ceiling. At its reported maximum, it is eleven thousand feet inside Class A airspace, where the regulations require an IFR flight plan, two-way radio, and a transponder. It carries none of the three.

V. The Night Flights

Section 107.29 of Title 14 governs night operations. No person may operate a small unmanned aircraft system at night unless the aircraft has lighted anti-collision lighting visible for at least three statute miles, with a flash rate sufficient to avoid a collision. The remote pilot may reduce the intensity of the lighting but may not extinguish it. The rule is explicit about the reason: other aircraft must be able to see the operator’s aircraft from three miles away in the dark.¹¹

Canada geese fly by day or night, depending on weather conditions and the brightness of the moon. They routinely cover two to three hundred miles in a single night of migration. Observers across the eastern flyways have documented the lines and vees “winging across night skies,” their flight sometimes so high that their incessant calls do not reach the earth. The migration is, in significant part, a night operation.¹²

The anti-collision lighting carried by the fleet on these night operations is zero statute miles’ worth. The goose bears no red position light on the left wingtip, no green on the right, no white tail light, no flashing strobe. The regulation requires three statute miles of visibility. The goose provides none. The remote pilot in command has filed no waiver and completed no knowledge test, because the goose has no remote pilot. It is the pilot.

VI. The Surveillance Gap

The national airspace system is a surveillance system. Section 91.215 requires transponders with altitude-reporting capability in Class A, Class B, and Class C airspace, within thirty nautical miles of a Class B primary airport, and above 10,000 feet mean sea level. Section 91.225 extended the requirement: after January 1, 2020, no person may operate an aircraft in Class A, B, or C airspace, in the Mode C veil, or in Class E airspace at or above 10,000 feet without ADS-B Out equipment broadcasting the aircraft’s position. Each person operating aircraft equipped with ADS-B Out must operate the equipment in transmit mode at all times.¹³

The goose is equipped with none of this. It carries no transponder, no Mode C altitude encoder, no ADS-B Out transmitter, no Remote ID broadcast module. Air traffic control cannot see it on its scopes. TCAS, the collision-avoidance system carried by every airliner, cannot interrogate it. The only sensor that detects a goose in flight is the human eye, and at 29,000 feet at night, the human eye detects nothing.¹⁴

There is one broadcast the goose does make. Remote ID requires drones to transmit their identity and location; the goose transmits its identity audibly, in the form of honking, at a volume sufficient to be heard from the ground. What it does not transmit is a Remote ID serial number, because it has never been issued one. The registration number that 14 CFR 48.205 requires to be displayed on the exterior of the aircraft does not appear on the exterior of the goose. The exterior of the goose displays feathers.³

VII. The Border Crossings

Twice each year, the fleet crosses the United States-Canada border. The autumn migration runs from September into November; the spring return reverses it. The crossings are not incidental. The entire fleet relocates between sovereign nations, overflying the border at altitudes between 980 and 3,300 feet, in formations visible on primary radar as unidentified primary targets with no associated flight plan.⁹

Part 99 of Title 14 governs operations in Air Defense Identification Zones. No person may operate an aircraft into, within, or across an ADIZ unless that person has filed a flight plan and made the position reports the part requires. The northern border ADIZ exists precisely to identify aircraft crossing between the United States and Canada. The goose crosses it without filing, without reporting, and without a discrete transponder code, because it has no transponder with which to squawk one.¹⁵

The continental air defense system, built at a cost measured in the tens of billions of dollars, is designed to detect and identify every aircraft approaching or crossing the nation’s borders. Every spring and every fall, several million aircraft cross the northern border. The system identifies none of them. The honking, if it were audible at the sector operations center, is not a recognized identification procedure.

VIII. The Collision Record

The National Wildlife Strike Database, maintained by the FAA with the Department of Agriculture, has recorded more than 276,000 wildlife strikes on civil aircraft between 1990 and 2022. The FAA estimates that only about twenty percent of strikes are actually reported. Waterfowl—ducks and geese—along with gulls and raptors, are the bird species that cause the most damage to civil aircraft in the United States. Ninety-two percent of strikes occur at 3,500 feet or lower: the altitude band in which the goose conducts the overwhelming majority of its operations.¹⁴¹⁶

The costs are measured in the hundreds of millions. The cost of wildlife strikes to the U.S. aviation industry was projected at $328 million for 2021 alone; the Fish and Wildlife Service has compiled figures exceeding $900 million in annual damages to U.S. civil and military aircraft; worldwide, bird strikes are estimated to cost the commercial airline industry a minimum of $1.1 billion per year. These are the costs of operating a national airspace system that shares its altitudes with an unregistered fleet.¹⁶¹⁷

On January 15, 2009, US Airways Flight 1549, an Airbus A320 departing New York’s LaGuardia Airport with 155 persons aboard, ingested Canada geese into both engines at 2,900 feet above ground level. Both engines failed. The crew ditched the aircraft in the Hudson River. All 155 survived. The FAA’s own strike report confirms the details: the birds were migratory Canada geese, the engines were destroyed, and the aircraft was damaged beyond repair. The unregistered fleet had downed a commercial airliner, and the NTSB’s probable cause reads, in the driest language available to the federal government, “ingestion of large birds.”¹⁸

It was not the first airframe. On September 22, 1995, a U.S. Air Force E-3 Sentry AWACS aircraft—call sign Yukla 27, assigned to the 962nd Airborne Air Control Squadron—struck a flock of Canada geese during takeoff from Elmendorf Air Force Base in Alaska and crashed 3,500 yards past the end of the runway, killing all 24 Canadian and U.S. airmen aboard. The Air Force’s own memorial account calls it one of the deadliest aircraft accidents in the service’s history. The geese involved held no airworthiness certificate.¹⁹

On January 15, 2009, the unregistered fleet ingested itself into both engines of an Airbus A320 at 2,900 feet. The NTSB’s probable cause, in the driest language available to the federal government, was “ingestion of large birds.”

IX. The Enforcement Arithmetic

The arithmetic is not complicated. The registration fee is five dollars per aircraft. The unregistered fleet numbers in the millions. At five dollars per aircraft, full compliance by the fleet would represent the largest single expansion of the registry in the agency’s history—tens of millions of dollars in registration revenue, every three years, in perpetuity, from operators who have never paid a cent.

The ratios are more striking than the revenue. The goose outweighs the registration threshold twenty-five to one. It outflies the altitude ceiling seven and a half to one on a routine migration, seventy-two and a half to one at its reported maximum. It outnumbers the entire registered recreational drone fleet. It operates at night, in controlled airspace, across international borders, above Flight Level 180, with no certificate, no medical, no radio, no transponder, no ADS-B, no Remote ID, no flight plan, no lighting, and no registration number on its exterior.

Section 91.113(b) requires that “vigilance shall be maintained by each person operating an aircraft so as to see and avoid other aircraft.” The right-of-way hierarchy gives balloons the right-of-way over everything, then gliders, then airships, then powered aircraft. The goose is a powered, heavier-than-air aircraft. It is required to see and avoid. It is required to give way to balloons. In practice, the vigilance is maintained entirely by the other party: the airline captain who sees the flock at the last second, the air traffic controller who issues the bird advisory, the airport wildlife biologist with the propane cannon. The see-and-avoid regime, as applied to the goose, is a regime in which only one side sees, and only one side avoids.²⁰

X. The Defense

The defense must be stated plainly, as this publication’s convention requires. It is, in fact, a strong defense. The statute says “contrivance invented, used, or designed to navigate, or fly in, the air.” A contrivance is a thing contrived—a product of human artifice. The goose was not invented. It was not designed, unless the design is attributed to a party the FAA has not named in any regulation. It evolved. The verbs in the definition—invented, used, designed—all imply a human actor doing the inventing, using, and designing. The goose does its own flying, with equipment it grew itself.

The Supreme Court has endorsed the everyday-speech reading of overbroad statutory definitions. In McBoyle v. United States, 283 U.S. 25 (1931), the Court held that an airplane was not a “motor vehicle” for purposes of the National Motor Vehicle Theft Act, because although “etymologically it is possible” for the term to cover an airplane, “in everyday speech, ‘vehicle’ calls up the picture of a thing moving on land.” By the same logic, in everyday speech, “aircraft” calls up the picture of a thing built by people, not a thing that honks.²¹

There is also the matter of the goose’s other regulator. Canada geese are protected under the Migratory Bird Treaty Act. The Fish and Wildlife Service, not the FAA, sets the hunting seasons that constitute the only fleet-reduction program the government operates. The FAA has never asserted jurisdiction over a bird, never issued an airworthiness directive against a flock, never grounded a single goose. The agency’s silence on the matter is total, and it has the virtue of being unanimous.

This publication has considered the defense and overruled it. The regulation says “a device that is used or intended to be used for flight in the air.” The goose is used for flight in the air. It is used by the goose. The FAA’s own Jetman interpretation held that a wing strapped to a man makes the man an aircraft; the goose arrives with the wing pre-installed, which is, if anything, a more complete compliance with the equipment requirement. The definition asks one question—does it fly—and the goose answers in the affirmative, twice a year, across an international border, at 29,000 feet.

The defense is that a goose is not a contrivance. The regulation asks one question—does it fly—and the goose answers in the affirmative, twice a year, across an international border, at 29,000 feet.

XI. Conclusion

Section 40102(a)(6) of Title 49 defines an aircraft as any contrivance invented, used, or designed to navigate or fly in the air. The Federal Aviation Administration requires every unmanned aircraft weighing more than 0.55 pounds to register at five dollars per aircraft, to display its number on its exterior, to operate within visual line of sight, and to broadcast its identity by Remote ID. The agency’s own legal interpretation holds that a man wearing a wing is an aircraft.

The Canada goose weighs up to fourteen pounds, more than twenty-five times the registration threshold. It migrates at 3,000 feet, seven and a half times the agency’s 400-foot ceiling, and has been reported at 29,000 feet, eleven thousand feet inside Class A airspace. It flies at night with no anti-collision lighting. It crosses the United States-Canada border twice a year with no flight plan, no radio contact, no transponder, and no ADS-B Out. It broadcasts its identity by honking. It has ingested itself into the engines of a commercial airliner carrying 155 persons and brought down a military surveillance aircraft with 24 crew. It outnumbers the agency’s 1.87 million registered drones.

No goose has ever filed a registration. None has ever been issued a number. The largest unregistered aircraft fleet in American airspace operates on a schedule no agency publishes, in airspace no certificate covers, under a definition the agency wrote itself.

Ergo.