SYLLABUS BY THE COURT:

1. Where it is alleged, in a mandamus action seeking inverse condemnation against Metropolitan Airports Commission (MAC) as airport operator, that petitioners' properties have been taken, destroyed, or damaged by a tortious invasion of their property rights by reason of noise, vibrations, dust, and oily grime claimed to have been created by aircraft using the airport and allegedly resulting in a loss of market values to those properties, it is held that a claim has been stated for which relief may be granted.

2. Minn.Const. art. 1, s 13, provides: 'Private property shall not be taken, destroyed or damaged for public use without just compensation therefor, first paid or secured.' However, not every inconvenience, annoyance, or loss of peace and quiet caused by aircraft using an airport will give rise to a cause of action in inverse condemnation against the airport operator. Inverse condemnation should be permitted only where such airflights constitute a direct and substantial invasion of property rights of such a magnitude that the owner of the property is deprived of its practical enjoyment and it would be manifestly unfair to the owner to sustain thereby a definite and measurable loss in market value which the property-owning public in general does not suffer. To justify an award of damages, these invasions of property rights must be repeated, aggravated, must not be of an occasional nature, and there must be a reasonable probability that they will be continued into the future.

3. Under Minn.St. s 360.107, subds. 1 and 16, MAC has all the powers necessary and convenient to accomplish the objects and perform the duties of maintaining, operating, and managing airports with all powers incident thereto. Thus, it has the power to take avigational easements in order to maintain and operate the airport.

4. The trial court correctly held that this was not a proper case for treatment as a class action on the grounds that there are a multitude of individual issues and an absence of common issues.

COUNSEL:

Mastor & Mattson and Charles R. Hall and Dygert & Gunn, Richard J. Gunn, Minneapolis, for appellants.

Oppenheimer, Brown, Wolff, Leach & Foster, and Gordon Shepard, Michael Berens, and Wayne G. Faris, St. Paul, for respondent.

Heard and reheard and considered and decided by the court en banc.

KELLY, Justice.

Petitioners appeal from an order of the Hennepin County District Court sustaining a demurrer to an dismissing their complaint and petition for writ of mandamus to compel respondent, Metropolitan Airports Commission of Minneapolis and St. Paul (MAC), to institute condemnation proceedings against the properties owned by petitioners and other similarly situated within their class and from the order denying their motion to have this action maintained as a class action. We reverse.

The central issues raised on this appeal are as follows:

(1) Does mandamus lie against MAC to compel it to institute condemnation proceedings to compensate landowners whose lands are claimed to have been taken or damaged by the operation of aircraft?

(2) Is a class action the proper and most efficient method for the adjudication of the rights of parties affected?

In connection with these issues, the parties have raised numerous related questions, some of which apparently were not considered by the trial court when it sustained respondent's demurrer.

This action was commenced by a group of property owners who reside under or near the take-off and landing flight paths for the Minneapolis-St. Paul International Airport. The 100 petitioners-appellants reside in the area of the city of Minneapolis, Hennepin County, generally referred to as South Minneapolis. They sought to bring this action as a class action on behalf of themselves and all others similarly situated. An affidavit filed in behalf of petitioners' motion before the district court indicates that the property affected would include approximately 27,565 homes, apartments, churches, places of business, and other buildings located in Hennepin, Ramsey, and Dakota counties. Petitioners compose a community cross section which includes the following occupations: A dentist, doctor, minister, lawyer, law professor, clerical and executive employees, a real estate appraiser, retired persons, a personnel manager, and a court reporter.

The class encompasses owners of all properties located within four corridors or sound cones emanating from the airport. These corridors extend generally northwest, northeast, southwest, and southeast from the airport. An outline of the four corridors is superimposed on a map accompanying the petitioners' complaint, but this depiction was produced as part of a study projecting airport activity levels for the year 1985 and thus it is not intended to be a definitive or uncompromising delineation of those properties which are affected in such a significant way as to make their owners proper parties to this lawsuit.

MAC, a public corporation, governed by Minn.St. 360.101 to 360.144, was created in and for the cities of Minneapolis and St. Paul pursuant to legislation enacted in 1943. L.1943, c. 500. The Minnesota Legislature set forth in the governing statute all of the details concerning its purposes, powers, membership, organization, financing, and jurisdiction. MAC was given the authority, resources, and responsibility for building and regulating the airport system that serves the Twin Cities metropolitan area. Respondent in its brief refers to a comprehensive summary of MAC's background and development contained in a recent law review article, Harper, The Minneapolis-St. Paul Metropolitan Airports Commission, 55 Minn.L.Rev. 363. The author who is a professor of transportation in the University of Minnesota School of Business Administration points out that Wold-Chamberlain Field was operated as an airport in the 1920's by the Minneapolis Park Board. With the advancement of technology and the increasing demand for airport services, Wold-Chamberlain Field has grown from a 2,000-foot sodded landing strip in 1920 to several concrete runways with lengths of 6,200, 8,250, and 10,000 feet in 1970. Most of this expansion took place during the late 1950's and early 1960's under the direction of MAC. While the airport facilities were growing in size, the type of aircraft using it likewise underwent a metamorphosis from internal combustion and turbine powered aircraft to jet propelled aircraft of larger size and greater number.

The airport facilities were financed in part through grants-in-aid from the Federal government to MAC as the sponsoring local agency. The grants were given pursuant to a number of assurances, conditions, and agreements by MAC relating to the operation and use of the airport. These assurances, conditions, and agreements remain binding upon MAC.

The determination of flight glide paths, take-off and landing directions and angles, movement of aircraft in general, and certification of the various types of aircraft which may use the airport are all under the authority of the secretary of transportation. 49 U.S.C.A., ss 1348, 1402, and 1421.

MAC has been accorded tax support by the legislature to further the operation of its facilities and develop airports. This support arises from the taxing authority given to Minneapolis and St. Paul to levy property taxes for MAC's benefit. This taxing authority is limited in amount, however, to a tax levy up to an annual 1-mill limit on assessed valuation to support operating budgets. Minn.St. 360.116. Since 1962, MAC's operating budget has not needed nor used this potential tax support. In addition, MAC has the authority to issue general obligation revenue bonds to a present maximum limit of $125,000,000, of which all but $9,000,000 have been issued. Economic forecasts made in connection with the proposal for a second major airport indicate that MAC has a capability to debt service out of airport-generated resources an additional $17,000,000 in bonding.

Petitioners allege that MAC in the operation and use of the Minneapolis-St. Paul International Airport has interfered with the use and enjoyment of their property to such an extent as to amount to a taking, requiring compensation under the Constitution of the State of Minnesota. Minn.Const. art. 1, s 13. In support of this contention, petitioners have alleged that respondent's operation has interfered with their use of the property in a number of ways. In their complaint, it is alleged, inter alia:

'By reason of defendant's use and operation of the Minneapolis-St.Paul International Airport, aircraft take off and land in great numbers at said airport, at irregular intervals at all hours of the day and night. Said aircraft fly at low altitudes within the airspace immediately above or in close proximity to the property of the plaintiffs.

'Such activity of the defendant has caused and is causing air and noise pollution to invade the property of the plaintiffs to such a degree that physical damage to such property has resulted and to such an extent that plaintiffs have been deprived of the free and unmolested use, possession and quiet enjoyment of their property.

'The activity of the defendant creates deafening, disturbing and frightening noises and vibrations to intrude upon the property of the plaintiffs, and causes dust and oily grime to pass over and to settle upon plaintiffs' property and in the homes and other structures located thereon.

'Defendant, by such activity, is perpetuating a continuing trespass and maintaining a continuing nuisance to such an unreasonable degree that plaintiffs have been greatly molested and annoyed thereby.

'Such acts of the defendant disrupt sleep, interfere seriously with entertainment and normal peaceful enjoyment and use of the property of the plaintiffs; interrupts and prevents normal conversation and communication, use and enjoyment of the telephone, television and radio; and creates fear, nervousness and apprehension on the part of the plaintiffs and others lawfully in and upon the property of the plaintiffs.

'The defendant, by such activity, has caused depreciation and diminution of the market value of the property of the plaintiffs, has confiscated and condemned such property, has interfered with the ownership, possession, enjoyment and value of such property and has caused a taking or damaging of the property of the plaintiffs for its use, without just compensation having been paid, without due process of law, and contrary to the Constitution and the Laws of the State of Minnesota and the Constitution of the United States of America.'

Because of the posture of this appeal, this court must assume that all of the foregoing allegations and contentions are true and base its decisions on that assumption.

1--3. Does mandamus lie against MAC to compel inverse condemnation?

Petitioners in this case have brought an action in inverse condemnation against MAC as a result of noise and pollution from the operation of airplanes directly over and near their properties. Inverse condemnation has been described as:

'* * * (T)he popular description of a cause of action against a governmental defendant to recover the value of property which has been taken in fact by the governmental defendant, even though no formal exercise of the power of eminent domain has been attempted by the taking agency.' Thornburg v. Port of Portland, 233 Or. 178, 180, note 1, 376 P.2d 100, 101 (1962).

In the development of the common law, courts have attempted to place their decisions in legal pigeonholes sometimes described as legal fictions. These legal fictions and theories have undergone not only minor changes, but also drastic changes to meet the varying contemporary needs of society and to improve our system of justice. The courts which have ordered inverse condemnation based upon overflights of airplanes have done so, in general, either on the theory of trespass or on the theory of nuisance. Perhaps at one time in the history of common law, a direct overflight by an airplane would unquestionably have been a trespass, as ownership of land included ownership of the airspace directly above to the periphery of the universe. In United States v. Causby, 328 U.S. 256, 260, 66 S.Ct. 1062, 1065, 90 L.Ed. 1206, 1210 (1946), the Supreme Court of the United States stated:

'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 coleum. But that doctrine has no place in the modern world. The air 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.'

On the other hand, should we consider giving trespass a new look? After all, if we can take away the rights of landowners to a part of the airspace directly above their land, can we not treat the invasion of their land by sound waves, fumes, oil, and what not as a recognizable trespass? A suggestion of this sort was made in Laird v. Nelms, 406 U.S. 797, 800, 92 S.Ct. 1899, 1901, 32 L.Ed.2d 499, 503 (1972), where Mr. Justice Rehnquist stated:

'* * * Perhaps the precise holding of United States v. Causby, supra, could be skirted by analogizing the pressure wave of air characterizing a sonic boom to the concussion that on occasion accompanies blasting, and treating the air wave striking the actual land of the property owner as a direct intrusion caused by the pilot of the plane in the mold of the classical common-law theory of trespass.'

Any discussion of whether inverse condemnation should be anchored to a nuisance theory, a trespass theory, a trespass theory with a new look, or on some combination of these theories should be preceded by a summary of United States Supreme Court decisions dealing with inverse condemnation, i.e., United States v. Causby, 328 U.S. 256, 66 S.Ct. 1062, 90 L.Ed. 1206 (1946); and Griggs v. Allegheny County, 369 U.S. 84, 82 S.Ct. 531, 7 L.Ed.2d 585 (1962).

The Causby case involved an action by the owner of property located directly below the take-off and landing glide path of an airport used extensively by military aircraft. No actual touching of the property's surface was found. Aircraft passing as low as 67 feet above his house cause the plaintiff much anxiety and discomfort in addition to ruining his chicken raising business. The supreme court initially brushed aside the argument based on the common-law principle that ownership of property extends to the periphery of the universe and held that Causby and suffered a compensable taking under the Fifth Amendment. While not defining precisely what elements are necessary for a taking by overflight, the court indicated several of the factors is found significant in reaching its decision. It thereby created confusion, however, because it used concepts of nuisance and trespass alternatively as the bases for the holding. Elements of trespass were relied upon by the court when it stated that although a direct touching of the property was not necessary, an invasion of that airspace above the ground which the landowner can occupy and use in connection with the land would be a taking. The court then went on to indicate that factors such as inconvenience, frequency, interference, and rights to the enjoyment and use of land played a significant role in reaching its decision -- concepts normally associated with nuisance actions. Thus, if a trespass is required, may only those people affected by direct overflight of their property recover? If a nuisance concept may be applied, then may all those whose use and enjoyment of their property is substantially interfered with recover regardless of the flightpath's location? In 1962, the Supreme Court decided Griggs v. Allegheny County, Supra, a case also involving direct overflight of property near an airport. Mr. Justice Douglas, speaking for the court, reaffirmed Causby, but did not clarify it.

The lower Federal courts which have dealt with this issue have almost unanimously allowed recovery only to those property owners located directly below the flight path. Batten v. United States, 306 F.2d 580, 583 (10 Cir. 1962). See, also, Avery v. United States, 330 F.2d 640, 645, 165 Ct.Cl. 357, 366 (1964); Bellamy v. United States, 235 F.Supp. 139, 140 (D.S.C.1964); Leavell v. United States, 234 F.Supp. 734, 739 (D.S.C.1964); and Neher v. United States, 265 F.Supp. 210, 216 (D.Minn. 1967). This approach more nearly resembles the trespass theory rather than the nuisance theory and for ease in reference, we refer to it as such.

The state court decisions have largely deviated from the Federal court pattern by allowing recovery both to those property owners directly beneath the flightpath and to those near the flightpath. However, this difference in result may not be inconsistent with the Federal court decisions because the Fifth Amendment to the United States Constitution refers only to a Taking of property, whereas many state constitutions similar to Minnesota's require compensation where private property is 'taken, destroyed or damaged.' Minn.Const. art. 1, s 13. Some state court opinions have cited similar provisions in their state constitutions as support for allowing recovery to property owners both under and near the flightpath. See, Martin v. Port of Seattle, 64 Wash.2d 309, 316, 391 P.2d 540, 545 (1964). A number of state courts, however, have dismissed the significance of this distinction and have allowed compensation to all parties whether in the flightpath or near it by interpreting the Causby and Griggs cases as allowing recovery based on a nuisance theory.