In these consolidated cases, defendants, husband and wife, appeal their convictions for manufacture and possession of a controlled substance. ORS 475.992. They contend that the trial court erred in denying their motion to suppress evidence seized from their property pursuant to a search warrant based on information obtained without a warrant by police officers who were riding in a helicopter looking for marijuana that they had heard was growing on defendants’ property. The question is whether that information was obtained in violation of defendants’ privacy rights under Article I, section 9, of the Oregon Constitution. Because the discovery of the marijuana by the police was the result of “a purposive intrusion into defendant’s privacy,” State v. Slowikowski, 307 Or 19, 27, 761 P2d 1315 (1988), for the express purpose of seeking out the contraband on defendants’ property, and was not merely an incidental observation made during a routine flight from one place to another, it was a search within the meaning of Article I, section 9. Further, because the search was conducted without a warrant or any exception to the warrant requirement, the evidence so obtained must be suppressed. Accordingly, we reverse.
Defendants live on approximately 14 acres of rural property. The front portion of the rectangularly shaped property is pasture land. The house is situated behind the pasture land on a flat bluff of approximately two acres. The remaining acreage is on an incline to the rear of the house and abuts BLM land. The property is enclosed from behind the house to the BLM line by a four-foot high animal fence topped with two strands of barbed wire. A barn and a poultry pen are in the enclosed area behind the house. There are “no trespassing” signs surrounding the property. The marijuana at issue here, 17 plants approximately five feet high, was growing in plastic buckets about 300 feet from the house. Most of the plants were under two large trees, 45 to 50 feet high, in a generally wooded area. The other plants were nearby among smaller trees. Defendant husband testified that he had placed the plants among the trees so that they would not be seen from the sides of his property or from the air.
Acting on a tip that marijuana was growing in the area of defendants’ property, two sheriffs deputies chartered a helicopter with a pilot to scout the area. When the helicopter *243arrived over defendants’ property, one of the deputies said that he spotted marijuana plants. The helicopter then tilted and circled above the spot three or four times to enable the other deputy to confirm the observation. There was conflicting testimony as to the altitude of the helicopter when the deputy said that he identified the marijuana. The pilot did not testify, and neither deputy was able to testify as to the precise altitude of the helicopter. One estimated that “we were pretty close to four or five hundred feet.” Defendants’ son estimated that the helicopter was 15 feet above the tallest trees.
Defendants challenge the accuracy of the affidavit on which the search warrant was based as to the altitude of the helicopter at the time of the deputies’ observations and also argue generally that there was no probable cause for issuance of the warrant. The challenge to the accuracy of the affidavit is in the nature of a motion to controvert and, pursuant to ORS 133.693(2), defendants have the burden to establish its inaccuracy. ORS 133.693(3). The affidavit stated that the helicopter was at 500 feet.1 Given our view of the case, however, we do not consider it significant whether the helicopter was less than 500 feet in the air when the deputy said that he saw marijuana plants.
Defendants’ general challenge is that the aerial observations constituted a warrantless search that violated their privacy rights and that, therefore, under Article I, section 9, of the Oregon Constitution and the Fourth Amendment,2 the search warrant based on those observations was invalid.3 Article I, section 9, protects both property and pri*244vacy interests. State v. Owens, 302 Or 196, 729 P2d 524 (1986); see also State v. Dixson/Digby, 307 Or 195, 766 P2d 1015 (1988). Given our conclusion that defendants’ privacy rights were violated, we need not decide whether their property rights were also violated. However, we point out that, at common law, a property owner had a property right upward usque ad coelum — to the heavens.4 With the development of aircraft, it became necessary to make accommodations between the rights of property owners and those engaged in commerce through the airspace. See United States v. Causby, 328 US 256, 66 S Ct 1062, 90 L Ed 1206 (1945). It is not necessary here to discuss the various approaches that have been taken to achieve that accommodation; we need only point out that their purpose has been to permit air commerce while, at the same time, to recognize property owners’ rights in the airspace above their land. In some instances, the intrusion has been characterized as a trespass; in others it has been characterized as a nuisance. See Atkinson et al v. Bernard, Inc., 223 Or 624, 355 P2d 229 (1960); Restatement (Second) Torts § 159 (1965).
The point is that the coming of aircraft and their use in commerce has not done away with the privacy right of property owners in and about their property, although it has reduced the extent to which they may exert property rights in the airspace above their land. Generally, people must put up with aircraft flying over their property above the minimum altitudes fixed by the FAA;5 however, there is no reason related to the accommodation of air travel why they must suffer the intrusion into their privacy that occurs when an aircraft hovers or circles over their property in an effort to *245scrutinize or spy on their activities on their protected premises. “[T]he privacy protected by Article I, section 9, is not the privacy that one reasonably expects but the privacy to which one has a right.” State v. Campbell, supra, 306 Or at 164 n 1. (Emphasis in original.) Because privacy rights are not confined to defendants’ house and its curtilage, State v. Dixson/Digby, supra, we need not decide whether the officers invaded the curtilage.6
It is one thing for an aircraft to fly over property at a safe altitude en route to a destination at a normal operating speed or at a speed that is necessary to maintain flight, during which some observations might be made of what is on the ground.7 That such a lawful observation might be made, however, does not mean that the police conduct here was not a search: “Whether police conduct is a search does not turn on whether its object could be discovered by conduct that is not a search.” State v. Campbell, supra, 306 Or at 166. It is quite another thing when the aircraft hovers, circles or makes numerous passes over the property in a determined effort to observe the property or activities in which the owners are engaged. “A determined official effort to see or hear what is not plain to a less determined observer may become an official ‘search.’ ” State v. Louis, 296 Or 57, 61, 672 P2d 708 (1983).
In 1859, when Article I, section 9, was adopted, there can be no doubt that occupying the airspace over a person’s property was a trespass, an unprivileged entry, although the framers could not then have foreseen that persons would be able to put themselves in that position. In Campbell, the court pointed out that, since 1859,
“the government’s ability to scrutinize the affairs of ‘the people’ has been enhanced by technological and organizational developments that could not have been foreseen then. * * * In *246deciding whether government practices that make use of these developments are searches, we must decide whether the practice, if engaged in wholly at the discretion of the government, will significantly impair ‘the people’s’ freedom from scrutiny, for the protection of that freedom is the principle that underlies the prohibition on ‘unreasonable searches’ set forth in Article I, section 9.” 306 Or at 171.
There can be no serious doubt that aircraft are technological enhancements that permit man to travel in the airspace and, in the case of helicopters, to hover above the ground. Although Deits, J., dissenting, agrees that aircraft, including helicopters, are technological enhancements, she concludes that the use of a helicopter in this case did not violate defendants’ privacy rights, apparently because the police were in the airspace where they had the right to be and their observations “took only a short time.” Therefore, she concludes, there was no search, in spite of the facts that the police were “surveilling” defendants’ property for marijuana and that the aircraft continued to circle and to hover at lower altitudes to “confirm” the officer’s observation. She fails to explain why, if the police may hover over the property for a “short time” to search for marijuana, they may not do it for a longer time and for any reason. To rely on the legality of the officers’ observation post in the air is no more valid than it was for the state to rely on the legality of the officers’ observation post in State v. Campbell, supra, from which the officers received signals from the electronic transmitter they had installed on the defendant’s automobile.
As Professor Amsterdam points out in “Perspectives on the Fourth Amendment,” 58 Minn L Rev, 349, 403 (1974), the ultimate question is “whether, if the particular form of surveillance practiced by the police is permitted to go unregulated by constitutional restraints, the amount of privacy and freedom remaining to citizens would be diminished to a compass inconsistent with the aims of a free and open society.” In our view, the hovering or circling of aircraft at low elevations, when engaged in for the purpose of finding out what is on, or what is happening on, a person’s property, would diminish the privacy and freedom of citizens to a point that is inconsistent with the free and open society envisioned by the framers of Oregon’s Constitution. It would be a “significant impairment of the people’s freedom from scrutiny.” State v. Campbell, supra, 306 Or at 170.
*247It is no answer to say, as Judge Deits says, that persons can easily detect aircraft when they are close to their property. Although the ability to detect them might make the intrusion more obvious, it does not make it any less intrusive.
The gist of Judge Rossman’s dissenting opinion is that, because searches from the air are effective as an “investigatory tool in the fight against illegal drugs,” 95 Or App at 251, we should overlook constitutional technicalities. If that were the test, we should hesitate to invalidate warrantless or general searches and wiretapping, as well as numerous other effective investigatory tools that our constitution prohibits. Judicial intervention, however, is “the instrument by which a free society imposes on itself the seldom welcome, sometimes dangerous, always indispensable restraints that keep it free.” Amsterdam, supra, 58 Minn L Rev at 353.
Reversed and remanded for a new trial.
There is evidence that there was an initial observation, after which the helicopter circled and descended. However, the information in the affidavit purports not to rely on any observations made after the initial one.
The officers’ conduct was not a search within the meaning of the Fourth Amendment. Florida v. Riley, 488 US _, 109 S Ct 693, 102 L Ed 2d 835 (1989); California v. Ciraolo, 476 US 210, 106 S Ct 1809, 90 L Ed 2d 210 (1986). Both of those cases were decided under the reasonable expectation of privacy analysis that originated with Katz v. United States, 389 US 576, 88 S Ct 507, 19 L Ed 2d 576 (1967), which has been rejected in analyzing privacy rights under the Oregon Constitution. State v. Campbell, 306 Or 157, 759 P2d 1040 (1988); compare Oliver v. United States, 466 US 214, 104 S Ct 1735, 80 L Ed 2d 214 (1984).
Defendants argue that their case can be factually distinguished from three aerial observation cases relied on by the state, in which we held that the evidence need not be suppressed: State v. Farkes, 71 Or App 155, 691 P2d 489 (1984), rev den 298 Or 704 (1985); State v. Bruno, 68 Or App 827, 683 P2d 1383, rev den 297 Or 824 (1984); State *244v. Davis, 51 Or App 827, 627 P2d 492, rev den 291 Or 368 (1981). However, Davis and Bruno were decided under the Fourth Amendment. Although Farkes was decided under Article I, section 9, as well as the Fourth Amendment, we made no separate state constitutional analysis. Therefore, those cases, although they may provide some guidance, do not govern our analysis under the state constitution. State v. Caraher, 293 Or 741, 653 P2d 942 (1982).
The complete phrase is: “cujus est solum ejus est usque ad coeleum” — which, “taken literally, means that he who has the soil owns upward unto heaven, and by analogy, downward to perdition.” Prosser and Keeton, Law of Torts 79 § 13 (5th ed 1984). See Butler v. Frontier Telephone Co., 186 NY 486, 79 NE 716 (1906).
FAA regulations, designed for safety, do not appear to impose a specific altitude restriction on helicopters. See 14 CFR § 91.79(d) (1986). It would be strange, indeed, to define one’s privacy rights under Article I, section 9, by administrative regulations. That is particularly true when, as with helicopters, there is no minimum altitude imposed.
Under some circumstances, the occupier of land must manifest his desire for privacy. State v. Dixson/Digby, supra. Here, defendants had done all that can be expected of them by posting “no trespassing” signs around their property. It would seem silly to require that they display large signs facing the heavens to notify persons in the airspace not to snoop.
In his dissenting opinion, Judge Rossman treats this case as if the officers were merely flying over defendants’ property and happened to see marijuana plants. That is not so. They had received information that defendants were growing marijuana and were engaged in a purposeful, determined effort, without a warrant, to find it on defendants’ property.