United States v. Causby/Opinion of the Court
Mr. Justice DOUGLAS delivered the opinion of the Court. 

This is a case of first impression. The problem presented is whether respondents' property was taken within the meaning of the Fifth Amendment by frequent and regular flights of army and navy aircraft over respondents' land at low altitudes. The Court of Claims held that there was a taking and entered judgment for respondent, one judge dissenting. 60 F.Supp. 751. The case is here on a petition for a writ of certiorari which we granted becuase of the importance of the question presented.

Respondents own 2.8 acres near an airport outside of Greensboro, North Carolina. It has on it a dwelling house, and also various outbuildings which were mainly used for raising chickens. The end of the airport's northwest-southeast runway is 2,220 feet from respondents' barn and 2,275 feet from their house. The path of glide to this runway passes directly over the property which is 100 feet wide and 1,200 feet long. The 30 to 1 safe glide angle  approved by the Civil Aeronautics Authority  passes over this property at 83 feet, which is 67 feet above the house, 63 feet above the barn and 18 feet above the highest tree.  The use by the United States of this airport is pursuant to a lease executed in May, 1942, for a term commencing June 1, 1942 and ending June 30, 1942, with a provision for renewals until June 30, 1967, or six months after the end of the national emergency, whichever is the earlier.

Various aircraft of the United States use this airport bombers, transports and fighters. The direction of the prevailing wind determines when a particular runway is used. The north-west-southeast runway in question is used about four per cent of the time in taking off and about seven per cent of the time in landing. Since the United States began operations in May, 1942, its four-motored heavy bombers, other planes of the heavier type, and its fighter planes have frequently passed over respondents' land buildings in considerable numbers and rather close together. They come close enough at times to appear barely to miss the tops of the trees and at times so close to the tops of the trees as to blow the old leaves off. The noise is startling. And at night the glare from the planes brightly lights up the place. As a result of the noise, respondents had to give up their chicken business. As many as six to ten of their chickens were killed in one day by flying into the walls from fright. The total chickens lost in that manner was about 150. Production also fell off. The result was the destruction of the use of the property as a commercial chicken farm. Respondents are frequently deprived of their sleep and the family has become nervous and frightened. Although there have been no airplane accidents on respondents' property, there have been several accidents near the airport and close to respondents' place. These are the essential facts found by the Court of Claims. On the basis of these facts, it found that respondents' property had depreciated in value. It held that the United States had taken an easement over the property on June 1, 1942, and that the value of the property destroyed and the easement taken was $2,000.

I. The United States relies on the Air Commerce Act of 1926, 44 Stat. 568, 49 U.S.C. § 171 et seq., 49 U.S.C.A. § 171 et seq., as amended by the Civil Aeronautics Act of 1938, 52 Stat. 973, 49 U.S.C. § 401 et seq., 49 U.S.C.A. § 401 et seq. Under those statutes the United States has 'complete and exclusive national sovereignty in the air space' over this country. 49 U.S.C. § 176(a), 49 U.S.C.A. § 176(a). They grant any citizen of the United States 'a public right of freedom of transit in air commerce  through the navigable air space of the United States.' 49 U.S.C. § 403, 49 U.S.C.A. § 403. And 'navigable air space' is defined as 'airspace above the minimum safe altitudes of flight prescribed by the Civil Aeronautics Authority.' 49 U.S.C. § 180, 49 U.S.C.A. § 180. And it is provided that 'such navigable airspace shall be subject to a public right of freedom of interstate and foreign air navigation.' Id. It is, therefore, argued that since these flights were within the minimum safe altitudes of flight which had been prescribed, they were an exercise of the declared right of travel through the airspace. The United States concludes that when flights are made within the navigable airspace without any physical invasion of the property of the landowners, there has been no taking of property. It says that at most there was merely incidental damage occurring as a consequence of authorized air navigation. It also argues that the landowner does not own superadjacent airspace which he has not subjected to possession by the erection of structures or other occupancy. Moreover, it is argued that even if the United States took airspace owned by respondents, no compensable damage was shown. Any damages are said to be merely consequential for which no compensation may be obtained under the Fifth Amendment.

It is ancient doctrine that at common law ownership of the land extended to the periphery of the universe-Cujus est solum ejus est usque ad coelum.  But that doctrine has no place in the modern world. The ai  is a public highway, as Congress has declared. Were that not true, every transcontinental flight would subject the operator to countless trespass suits. Common sense revolts at the idea. To recognize such private claims to the airspace would clog these highways, seriously interfere with their control and development in the public interest, and transfer into private ownership that to which only the public has a just claim.

But that general principle does not control the present case. For the United States conceded on oral argument that if the flights over respondents' property rendered it uninhabitable, there would be a taking compensable under the Fifth Amendment. It is the owner's loss, not the taker's gain, which is the measure of the value of the property taken. United States v. Miller, 317 U.S. 369, 63 S.Ct. 276, 87 L.Ed. 336, 147 A.L.R. 55. Market value fairly determined is the normal measure of the recovery. Id. And that value may reflect the use to which the land could readily be converted, as well as the existing use. United States v. Powelson, 319 U.S. 266, 275, 63 S.Ct. 1047, 1053, 87 L.Ed. 1390, and cases cited. If, by reason of the frequency and altitude of the flights, respondents could not use this land for any purpose, their loss would be complete.  It would be as complete as if the United States had entered upon the surface of the land and taken exclusive possession of it.

We agree that in those circumstances there would be a taking. Though it would be only an easement of flight which was taken, that easement, if permanent and not merely temporary, normally would be the equivalent of a fee interest. It would be a definite exercise of complete dominion and control over the surface of the land. The fact that the planes never touched the surface would be as irrelevant as the absence in this day of the feudal livery of seisin on the transfer of real estate. The owner's right to possess and exploit the land-that is to say, his beneficial ownership of it-would be destroyed. It would not be a case of incidental damages arising from a legalized nuisance such as was involved in Richards v. Washington Terminal Co., 233 U.S. 546, 34 S.Ct. 654, 58 L.Ed. 1088, L.R.A.1915A, 887. In that case property owners whose lands adjoined a railroad line were denied recovery for damages resulting from the noise, vibrations, smoke and the like, incidental to the operations of the trains. In the supposed case the line of flight is over the land. And the land is appropriated as directly and completely as if it were used for the runways themselves.

There is no material difference between the supposed case and the present one, except that here enjoyment and use of the land are not completely destroyed. But that does not seem to us to be controlling. The path of glide for airplanes might reduce a valuable factory site to grazing land, an orchard to a vegetable patch, a residential section to a wheat field. Some value would remain. But the use of the airspace immediately above the land would limit the utility of the land and cause a diminution in its value.  That was the philosophy of Portsmouth Harbor Land & Hotel Co. v. United States, 260 U.S. 327, 43 S.Ct. 135, 67 L.Ed. 287. In that case the petition alleged that the United States erected a fort on nearby land, established a battery and a fire control station there, and fired guns over petitioner's land. The Court, speaking through Mr. Justice Holmes, reversed the Court of Claims which dismissed the petition on a demurrer,  olding that 'the specific facts set forth would warrant a finding that a servitude has been imposed.'  260 U.S. at page 330, 43 S.Ct. at page 137, 67 L.Ed. 287. And see Delta Air Corp. v. Kersey, 193 Ga. 862, 20 S.E.2d 245, 140 A.L.R. 1352. Cf. United States v. 357.25 Acres of Land, D.C., 55 F.Supp. 461.

The fact that the path of glide taken by the planes was that approved by the Civil Aeronautics Authority does not change the result. The navigable airspace which Congress has placed in the public domain is 'airspace above the minimum safe altitudes of flight prescribed by the Civil Aeronautics Authority.' 49 U.S.C. § 180, 49 U.S.C.A. § 180. If that agency prescribed 83 feet as the minimum safe altitude, then we would have presented the question of the validity of the regulation. But nothing of the sort has been done. The path of glide governs the method of operating-of landing or taking off. The altitude required for that operation is not the minimum safe altitude of flight which is the downward reach of the navigable airspace. The minimum prescribed by the authority is 500 feet during the day and 1000 feet at night for air carriers (Civil Air Regulations, Pt. 61, §§ 61.7400, 61.7401, Code Fed.Reg.Cum.Supp., Tit. 14, ch. 1) and from 300 to 1000 feet for other aircraft depending on the type of plane and the character of the terrain. Id., Pt. 60, §§ 60.350-60.3505, Fed.Reg.Cum.Supp., supra. Hence, the flights in question were not within the navigable airspace which Congress placed within the public domain. If any airspace needed for landing or taking off were included, flights which were so close to the land as to render it uninhabitable would be immune. But the United States concedes, as we have said, that in that event there would be a taking. Thus, it is apparent that the path of glide is not the minimum safe altitude of flight within the meaning of the statute. The Civil Aeronautics Authority has, of course, the power to prescribe air traffic rules. But Congress has defined navigable airspace only in terms of one of them-the minimum safe altitudes of flight.

We have said that the airspace is a public highway. Yet it is obvious that if the landowner is to have full enjoyment of the land, he must have exclusive control of the immediate reaches of the enveloping atmosphere. Otherwise buildings could not be erected, trees could not be planted, and even fences could not be run. The principle is recognized when the law gives a remedy in case overhanging structures are erected on adjoining land.  The landowner owns at least as much of the space above the ground as the can occupy or use in connection with the land. See Hinman v. Pacific Air Transport, 9 Cir., 84 F.2d 755. The fact that he does not occupy it in a physical sense-by the erection of buildings and the like-is not material. As we have said, the flight of airplanes, which skim the surface but do not touch it, is as much an appropriation of the use of the land as a more conventional entry upon it. We would not doub  that if the United States erected an elevated railway over respondents' land at the precise altitude where its planes now fly, there would be a partial taking, even though none of the supports of the structure rested on the land.  The reason is that there would be an intrusion so immediate and direct as to subtract from the owner's full enjoyment of the property and to limit his exploitation of it. While the owner does not in any physical manner occupy that stratum of airspace or make use of it in the conventional sense, he does use it in somewhat the same sense that space left between buildings for the purpose of light and air is used. The superadjacent airspace at this low altitude is so close to the land that continuous invasions of it affect the use of the surface of the land itself. We think that the landowner, as an incident to his ownership, has a claim to it and that invasions of it are in the same category as invasions of the surface. 

In this case, as in Portsmouth Harbor Land & Hotel Co. v. United States, supra, the damages were not merely consequential. They were the product of a direct invasion of respondents' domain. As stated in United States v. Cress, 243 U.S. 316, 328, 37 S.Ct. 380, 385, 61 L.Ed. 746, '* * * it is the character of the invasion, not the amount of damage resulting from it, so long as the damage is substantial, that determines the question whether it is a taking.'

We said in United States v. Powelson, supra, 319 U.S. at page 279, 63 S.Ct. at page 1054, 87 L.Ed. 1390, that while the meaning of 'property' as used in the Fifth Amendment was a federal question, 'it will normally obtain its content by reference to local law.' If we look to North Carolina law, we reach the same result. Sovereignty in the airspace rests in the State 'except where granted to and assumed by the United States.' Gen.Stats. 1943, § 63-11. The flight of aircraft is lawful 'unless at such a low altitude as to interfere with the then existing use to which the land or water, or the space over the land or water, is put by the owner, or unless so conducted as to be imminently dangerous to persons or property lawfully on the land or water beneath.' Id., § 63-13. Subject to that right of flight, 'ownership of the space above the lands and waters of this State is declared to be vested in the several owners of the surface beneath.' Id. § 63-12. Our holding that there was an invasion of respondents' property is thus not inconsistent with the local law governing a landowner's claim to the immediate reaches of the superadjacent airspace.

The airplane is part of the modern environment of life, and the inconveniences which it causes are normally not compensable under the Fifth Amendment. The airspace, apart from the immediate reaches above the land, is part of the public domain. We need not determine at this time what those precise limits are. Flights over private land are not a taking, unless they are so low and so frequent as to be a direct and immediate interference with the enjoyment and use of the land. We need not speculate on that phase of the present case. For the findings of the Court of Claims plainly establish that there was a diminution in value of the property and that the frequent, low-level flights were the direct and immediate cause. We agree with the Court of Claims that a servitude has been imposed upon the land.

II. By § 145(1) of the Judicial Code, 28 U.S.C. § 250(1), 28 U.S.C.A. § 250(1), the Court of Claims has jurisdiction to hear and determine 'All claims (except for pensions) founded upon the Constitution of the United States or * * * upon any contract, express or implied, with the Government of the United States.'

We need not decide whether repeated trespasses might give rise to an implied contract. Cf. Portsmouth Harbor Land & Hotel Co. v. United States, supra. If there is a taking, the claim is 'founded upon the Constitution' and within the jurisdiction of the Court of Claims to hear and determine. See Hollister v. Benedict & Burnham Mfg. Co., 113 U.S. 59, 67, 5 S.Ct. 717, 721, 28 L.Ed. 901; Hurley v. Kincaid, 285 U.S. 95, 104, 52 S.Ct. 267, 269, 76 L.Ed. 637; Yearsley v. W. A. Ross Construction Co., 309 U.S. 18, 21, 60 S.Ct. 413, 415, 84 L.Ed. 554. Thus, the jurisdiction of the Court of Claims in this case is clear.

III. The Court of Claims held, as we have noted, that an easement was taken. But the findings of fact contain no precise description as to its nature. It is not described in terms of frequency of flight, permissible altitude, or type of airplane. Nor is there a finding as to whether the easement taken was temporary or permanent. Yet an accurate description of the property taken is essential, since that interest vests in the United States. United States v. Cress, supra, 243 U.S. 328, 329, 37 S.Ct. 385, 386, 61 L.Ed. 746, and cases cited. It is true that the Court of Claims stated in its opinion that the easement taken was permanent. But the deficiency in findings cannot be rectified by statements in the opinion. United States v. Esnault-Pelterie, 299 U.S. 201, 205, 206, 57 S.Ct. 159, 161, 162, 81 L.Ed. 123; United States v. Seminole Nation, 299 U.S. 417, 422, 57 S.Ct. 283, 287, 81 L.Ed. 316. Findings of fact on every 'material issue' are a statutory requirement. 53 Stat. 752, 28 U.S.C. § 288, 28 U.S.C.A. § 288. The importance of findings of fact based on evidence is emphasized here by the Court of Claims' treatment of the nature of the easement. It stated in its opinion that the easement was permanent because the United States 'no doubt intended to make some sort of arrangement whereby it could use the airport for its military planes whenever it had occasion to do so.' (60 F.Supp. 758.) That sounds more like conjecture rather than a conclusion from evidence; and if so, it would not be a proper foundation for liability of the United States. We do not stop to examine the evidence to determine whether it would support such a finding, if made. For that is not our function. United States v. Esnault-Pelterie, supra, 299 U.S. at page 206, 57 S.Ct. at page 162, 81 L.Ed. 123.

Since on this record it is not clear whether the easement taken is a permanent or a temporary one, it would be premature for us to consider whether the amount of the award made by the Court of Claims was proper.

The judgment is reversed and the cause is remanded to the Court of Claims so that it may make the necessary findings in conformity with this opinion.

Reversed.

Mr. Justice JACKSON took no part in the consideration or decision of this case.

Notes

 A 30 to 1 glide angle means one foot of elevation or descent for every 30 feet of horizontal distance.

 Military planes are subject to the rules of the Civil Aeronautics Board where, as in the present case, there are no Army or Navy regulations to the contrary. Cameron v. Civil Aeronautics Board, 7 Cir., 140 F.2d 482.

 The house is approximately 16 feet high, the barn 20 feet, and the tallest tree 65  eet.

 'Air commerce' is defined as including 'any operation or navigation of aircraft which directly affects, or which may endanger safety in, interstate, overseas, or foreign air commerce.' 49 U.S.C. § 401(3), 49 U.S.C.A. § 401(3).

 1 Coke, Institutes, 19th Ed. 1832, ch. 1, § 1(4a); 2 Blackstone, Commentaries, Lewis Ed. 1902, p. 18; 3 Kent, Commentaries, Gould Ed. 1896, p. 621.

 The destruction of all uses of the property by flooding has been held to constitute a taking. Pumpelly v. Green Bay Co., 13 Wall. 166, 20 L.Ed. 557; United States v. Lynah, 188 U.S. 445, 23 S.Ct. 349, 47 L.Ed. 539; United States v. Welch, 217 U.S. 333, 30 S.Ct. 527, 54 L.Ed. 787, 28 L.R.A.,N.S., 385, 19 Ann.Cas. 680.

 It was stated in United States v. General Motors Corp., 323 U.S. 373, 378, 65 S.Ct. 357, 359, 89 L.Ed. 311, 156 A.L.R. 390, 'The courts have held that the deprivation of the former owner rather than the accretion of a right or interest to the sovereign constitutes the taking. Governmental action short of acquisition of title or occupancy has been held, if its effects are so complete as to deprive the owner of all or most of his interest in the subject matter, to amount to a taking.' The present case falls short of the General Motors case. This is not a case where the United States has merely destroyed property. It is using a part of it for the flight of its planes.

Cf. Warren Township School Dist. v. Detroit, 308 Mich. 460, 14 N.W.2d 134; Smith v. New England Aircraft Co., 270 Mass. 511, 170 N.E. 385, 69 A.L.R. 300; Burnham v. Beverly Airways, Inc., 311 Mass. 628, 42 N.E.2d 575.

 On remand the allegations in the petition were found not to be supported by the facts. 64 Ct.Cl. 572.

 Baten's Case, 9 Coke R. 53b; Meyer v. Metzler, 51 Cal. 142; Codman v. Evans, 7 Allen 431, 89 Mass. 431; Harrington v. McCarthy, 169 Mass. 492, 48 N.E. 278, 61 Am.St.Rep. 298. See Ball, The Vertical Extent of Ownership in Land, 76 U.Pa.L.Rev. 631, 658 671.

 It was held in Butler v. Frontier Telephone Co., 186 N.Y. 486, 79 N.E. 716, 11 L.R.A.,N.S., 920, 116 Am.St.Rep. 563, 9 Ann.Cas. 858, that ejectment would lie where a telephone wire was strung across the plaintiff's property, even though it did not touch the soil. The court stated pages 491, 492 of 186 N.Y., page 718 of 79 N.E.: '* * * an owner is entitled to the absolute and undisturbed possession of every part of his premises, including the space above, as much as a mine beneath. If the wire had been a huge cable, several inches thick and but a foot above the ground, there would have been a difference in degree, but not in principle. Expand the wire into a beam supported by posts standing upon abutting lots without touching the surface of plaintiff's land, and the difference would still be one of degree only. Enlarge the beam into a bridge, and yet space only would be occupied. Erect a house upon the bridge, and the air above the surface of the land would alone be disturbed.'

 See Bouve, Private Ownership of Navigable Airspace Under the Commerce Clause, 21 Amer.Bar Assoc.Journ. 416, 421-422; Hise, Ownership and Sovereignty of the Air, 16 Ia.L.Rev. 169; Eubank, The Doctrine of the Airspace Zone of Effective Possession, 12 Boston Univ.L.Rev. 414.