Trespass by aircraft: is section 76(1) Civil Aviation Act 1982 now redundant?

Rights of overflight have been a vexed issue for many years. Frequently it comes to a head in the context of low level operations around airports, but it is not just about large commercial aircraft approaching and departing from major airports. It is important in the ‘novel aerospace’ world where, for example, open category drones are limited to 400’ above ground level, and we anticipate that new technology will enable more aircraft to exploit the airspace in closer proximity to one another, and in higher volumes, than hitherto.

In this context, two recent cases looked at whether an aircraft may trespass by passing through a landowner’s airspace. This should afford a useful opportunity to take stock on where the law stands. It might be unfair to suggest that drone cases are like the proverbial buses: you wait for ages and then two come along at once. Actually, not quite, since the recent judgments were in May 2023 and February 2025, and we missed an interim judgment in November 2021. However, although the previous trespass case involving low flying aircraft was in 1978, neither of these judgments took the opportunity to give a definitive ruling on the issue.

Trespass in general

The doctrine of trespass relies on the presence of a person or thing on land belonging to another, when authorisation has not been granted. It is a strict liability tort, and thus the landowner is in principle entitled to an injunction to require someone to leave and, if there is a credible threat of a repeat, to prohibit future entry onto the land. 

The fact that it is a strict liability tort avoids the need for a landowner to prove damage: mere presence on another’s land without consent is enough to engage the tort. That is not to say that damages may not be awarded where there is additional loss or damage.

Trespass and airspace

Various property law cases, and one involving a crane which swung over the claimant’s land, have confirmed the principle that encroachment into airspace over a neighbour’s land can constitute a trespass. A number of these cases relied on the Latin maxim cujus est solum, ejus est usque ad coelum (whose is the soil, his is also the heavens), but only in the context of the airspace immediately above the land.

Those cases also only dealt with buildings or other things on the ground. So far as aircraft are concerned, what is now the Civil Aviation Act 1982 modifies the common law position. Section 76 balances the interests of aircraft operators and the owners of land over which they fly. Section 76(1) provides that overflight at a reasonable height does not give rise to an action in trespass or nuisance, against the quid pro quo in section 76(2) of strict liability in the event of loss or damage.

Wording of this nature has been on the statute books in the UK since 1920.

Section 76(1) is clear that it only exempts the overflight itself from being a trespass or a nuisance: if it can be shown that the flight caused loss or damage, or otherwise constituted a nuisance, then damages would be recoverable. Of course a nuisance can also be occasioned without overflight where the question of trespass does not arise. However for there to be a trespass there must be an encroachment, without authority, by a person or an object on land owned or possessed by another.

So, while entry into airspace owned by another person is in principle be a trespass, the aircraft owner has a defence so long as the flight is at a reasonable height, complies with all regulations, and causes no additional loss or damage. This necessitates a two step analysis: first, does the landowner own the airspace? Only if so do you address whether the flight was at a reasonable height. 

Ownership of airspace

This obviously begs the question of ownership rights in airspace. If there is no entry into ‘land’ owned by another, there can be no trespass. This was examined thoroughly in Bernstein of Leigh v Skyviews & General Ltd [1978] QB 479, when a landowner objected to overflight of his land for the purpose of photographing his property. The competing issue was whether landowners own the airspace at all heights over their land, or only to some lower height. The court comprehensively rejected the ancient Latin maxim and concluded that the landowner only owned the “airspace necessary for the reasonable enjoyment and use of the land and buildings on it”. 

Against that background the court concluded that “the defendants' aircraft did not infringe any rights in the plaintiff’s air space”. The mere presence of the aircraft, for a single flight several hundred feet above ground level, did not interfere in any way with the use of the land. Taking a photograph was not an actionable nuisance. For those reasons no trespass was committed. Even if it had been, the flight was at a ‘reasonable’ height for the purposes of the predecessor statute to s.76 Civil Aviation Act 1982.

In that sense the judgment was clear that there was no trespass and it seems to follow that the judge did not believe the landowner owned the airspace at the height the aircraft was flying. However, the judgment is of limited help in determining either: 

• the vertical extent of the landowner’s ownership, or 
• what is a ‘reasonable’ height for the purposes of the statutory defence.

What did we know/not know before Anglo-International and MBR Acres?

That is the background to two recent High Court cases: Anglo-International Upholland Ltd -v- Wainwright and Persons Unknown (KB-2023-MAN-000209, 5 May 2023) and MBR Acres Ltd and others -v-Curtin [2025] EWHC 331 (KB), 19 February 2025. 

Before these judgments, the traditional analysis of trespass and overflight was as follows:

• The starting point is that trespass could occur by mere presence of an aircraft or drone in airspace owned by the landowner;
• While we know that the landowner owns the airspace which is “necessary for the reasonable enjoyment and use of the land and buildings on it”, the only guidance as to how high that extends is that a flight “many hundreds of feet above the ground” did not infringe that landowner’s rights; and
• While the operator has a defence to trespass, even if flying in airspace owned by the landowner, so long as the flight is at a “reasonable height”, we don’t know what that reasonable height is.

What were Anglo-International and MBR Acres all about?

Although both involved applications for injunctions to prevent drone flight over the owners’ land, they were very different cases, in background and outcome.

Anglo-International was an application by the owners of a derelict (and dangerous) college building which had become popular for trespassers. It had a substantial perimeter and despite considerable security expense the owners were unable to keep trespassers out. The internet featured many photos and videos of trespassers on the site. 

In a short (4 page) judgment, following a hearing which the named defendant did not attend, the judge rapidly decided that the purpose of the flights was mischievous. The complaint was not about the ‘simple act of flying’ but about the objective of the flights, namely to obtain pictures and footage which would facilitate and encourage further trespass. This meant that the height could not be said to be reasonable for the purposes of section 76(1).

The reasoning is not crystal clear, but the judge appears to have concluded that there was a trespass. Certainly section 76 did not protect the drone operators from the issue of an injunction. However, as with Bernstein, there was no consideration of the height the drones were flying, or whether this was within the landowner’s airspace. 

In contrast MBR Acres entailed substantial contested proceedings over many years. It involved protests against breeding animals for medical testing. The judgment clearly reflected both the right to protest, the limits of that protest, and the landowner’s right to conduct its business without interference.

The case was originally pursued against multiple named defendants, but also against ‘persons unknown’. This entailed an adjournment, after the main trial in April/May 2023, to await the outcome of a Supreme Court appeal in a case brought by Wolverhampton City Council against travellers which addressed many public law issues around injunctions ‘contra mundum’.

In November 2021 the judge declined to order an interim injunction against future drone use. It was clear that he was not attracted to the landowner’s arguments based on trespass.

By the time of the trial itself – before the same judge who heard the interim injunction application - the action was only pursued against one named defendant, although injunctions were still sought against persons unknown. The lengthy judgment is detailed and closely reasoned, but much of the case involved trespass on the ground and so much of the judgment has nothing to do with drones.

MBR Acres: the outcome on drone flight

The short point is that the judge declined to order injunctions against either the named defendant or against persons unknown. He accepted that the named defendant had only ever flown drones at least 50 metres above the landowner’s site and that those flights – adopting the test applied in Bernstein – did not interfere with the ordinary use of the land.

While the judge was satisfied that persons unknown might fly drones over the site in the future, the landowner had not been able to establish reliably the height at which drones had been flown in the past or was likely to be flown in the future. Without that evidence it was impossible to conclude there was a credible risk that future drone flights would amount to a trespass. 

The judge in MBR Acres was clearly influenced by the fact that the complaint was not really about the flight itself but about the filming. He did not believe the law of trespass would deliver an effective remedy against that, because much the same filming could be carried out without overflying the claimant’s site, or even from adjacent land. In his view the proper claim was really nuisance, harassment, misuse of private information or data protection – most of which have advanced significantly since 1978. But these causes of action were not pleaded, so the judge could not award relief. In contrast to the approach in Anglo-International, the judge was clear that the purpose of the flight was irrelevant: either it was a trespass, because it was within the site owner’s airspace, or not.

Despite frequently noting that trespass was a strict liability tort, he seemed to have concluded that there needed to be interference with the land as well as mere presence in the landowner’s airspace. There was no attempt to determine the vertical extent of the landowner’s airspace and consequently no consideration of a reasonable height below that for the purposes of the section 76(1) defence. Indeed section 76 does not feature in the judgment.

The other point that is notable about the case is that there was no material reference to the impact of drone regulation. Section 76(1) would only protect the drone operator if he had complied fully with all relevant regulations. While the judge did not rely on some of the evidence about the height of drone flight, evidence was quoted in the judgment of drones being flown at the height of a single storey building or within ten feet of individuals, or out of line of sight of the operator. The named defendant also made reference to using drones weighing 249 grams because of the different regulations applicable to heavier vehicles. Despite this there was no consideration of whether the drone flying – especially by the unknown pilots – complied with relevant regulations. 

So where are we after Anglo-International and MBR Acres?

The obvious conclusion is that Anglo-International made it easier to secure an injunction against overflight, but MBR Acres reversed that. Therefore drone operators may have greater latitude to fly over third party land. However the position is not straightforward.

The essence of the MBR Acres judgment, coupled with Bernstein, seems to be that there has to be interference with the use of the land, not merely presence in airspace belonging to the landowner. There is a logic that the test expounded in Bernstein means that the only airspace that belongs to the landowner is airspace that is critical to the use of the land – in other words, as soon as an aircraft enters that airspace, people lawfully on that land cannot go about their normal activity. As it happens there was certainly evidence that some of the lower flying drones did inhibit activity at the MBR Acres site, but this did not assist the landowner because of the inability to connect those flights with the unknown operators.

If this is indeed the correct understanding of the judgment, it effectively makes section 76(1) redundant. Section 76(1) says there is no action for trespass in circumstances where there is no other effect on the landowner, but MBR Acres and Bernstein seem to say there is no trespass until there is an effect on the landowner. On a plain reading, the statutory provisions which have been in place for over a hundred years presume that there is a trespass by virtue of mere presence in the landowner’s airspace. They contemplate flight in that zone, which has no effect on the landowner, and in that event there is no action for trespass, so long as the height is reasonable and the flight otherwise lawful. On a natural reading of the statute, one would expect a ‘buffer zone’ between the point at which the landowner is affected and the edge of the landowner’s airspace.

The judgments also fail to help with what is meant by a reasonable height for the statutory defence. It seems to follow that if the trespass only occurs when there is interference with the use of the land, then there cannot be a height below that which is nevertheless reasonable. But neither case addressed the point.

Does this make a real difference in practice? Perhaps not, in that the prospect of securing a future injunction, especially against unknown actors, may be low unless the landowner can show a real prospect of interference. But it also begs the question of the interaction with section 76(2) – the strict liability for ‘material loss or damage’ caused by overflying aircraft. There is a dearth of caselaw on claims for damage due to overflight and these two cases do not assist with whether there is a point at which there is interference with the use of the land but no material loss that is recoverable under section 76(2).

If it is correct that advances in technology will increase volumes of low flying aircraft, these issues are unlikely to go away. To some degree these cases were coloured by the fact that, from the landowners’ perspective, these flights were mischievous. One hopes a different view would be taken if the flights were for urgent transport of medical samples, as has been trialled recently in central London. Different considerations may apply to high traffic volumes in the vicinity of a commercial drone delivery depot. Ultimately this goes to the social acceptability of future drone operations, and we welcome further policy development on that issue.