Unmanned Aerial Devices (UADs) are considered to be a type of aircraft by the International Civil Aviation Authority, an organisation of the United Nations. This means that UADs must comply with applicable aviation law. In the UK, this falls under the remit of the UK's Civil Aviation Authority (CAA).

As the number of UADs in the skies increases, so does the likelihood of collision.  In the US, there have been 25 separate near mid-air collisions between UADs and helicopters and planes since 1 June 2014.  Closer to home, in the UK, there have also been several near misses, including a recent incident with a passenger jet and a UAD near Heathrow Airport in December 2014, which the CAA gave an "A" rating, meaning there was a "serious risk of collision".  Such stories highlight the fact that, far from being toys, UADs have the potential to cause catastrophic damage which makes effective aviation regulation essential.

The UK position

UADs weighing less than 20kg

UADs weighing less than 20kg (defined by the CAA as "Small Unmanned Aircraft") are exempt from most of the regulations normally applicable to manned aircraft.  For such UADs, unless permission is obtained from the CAA, pilots must avoid flying them over or within 150 metres of a congested area or an open-air assembly of more than 1,000 persons, and 50 metres of another person, vessel, vehicle or structure which is not under control of the pilot (Air Navigation Order 2009).  This appears to mean that you cannot fly a UAD in the park if there are passers-by who are within 50m of the device.

Commercial UADs and UADs weighing 20kg or more

Permission to use UADs must always be obtained from the CAA where the use is commercial, even if the UAD weighs less than 20kg.  The rules also state that a pilot must be reasonably satisfied that the flight can safely be made, and that he can maintain direct, unaided visual contact with the aircraft sufficient to monitor the UAD's flight path in relation to other aircraft, persons, vehicles, vessels or structures for the purposes of avoiding collisions.  At present, more than 300 companies and public bodies have permission to fly UADs in the UK (compared to just 30 in January 2013), with hundreds more applications expected this year.

For UADs which weigh more than 20kg, stricter rules apply.  Permission to use them must be obtained from the CAA and a pilot qualification is required.  There are also airworthiness and registration requirements.

Enforcement

The CAA has rules to cater for the situation where a UAD strays beyond the "line of sight" of its pilot (500 metres horizontally and 400 feet vertically from the pilot).  The CAA can take legal action against UAD owners who break the rules.  In 2014, a man was reportedly fined £800 and ordered to pay costs after he pleaded guilty of flying a UAD within 50m of the Jubilee Bridge on the Walney channel and flying over a BAE Systems submarine testing facility.  This was the first offence involving recreational use of a UAD, but as their popularity increases, it is likely that more will follow.

Having said that, it is hard to imagine the regulations on UADs under 20kg being enforced against innocent consumers playing with their new gadget in the park.  Remote controlled toys are regularly flown in public spaces within the 150m of congested areas.  Are all those children flying their toys in their local parks and gardens supposed to apply for permission for the CAA?

It is more likely that enforcement action will be taken against those exploiting UADs for commercial purposes without taking applicable regulation into account.  However, dangerous use of a non-commercial UAD (e.g. which could put an aircraft at risk) could result in a prosecution.

US position

In the US, the use of UADs, whatever their size, is regulated by the Federal Aviation Administration (FAA).  A small UAD (under 25kg) can currently only be flown for commercial purposes if the user receives a Certificate of Authorisation or an exemption under the FAA Modernization and Reform Act 2012.

In February 2014, the FAA released proposed new rules governing the use of commercial UADs, which would apply to small UADs weighing up to 25kg.  Operators of commercial UADs would: be able to fly up to a maximum speed of 100mph and up to 500 feet; not be allowed to fly in airport flightpaths or restricted airspace areas; have to be at least 17 years old; and pass certain tests.  While the FAA claims it has attempted to be flexible in writing these draft regulations, some businesses have raised concerns they are still too restrictive.

Conclusion

Finding a compromise between safe and regulated airspace, both within and across national boundaries, while allowing the potential of UADs to be realised, is a challenge which no country has successfully met to date although many governments are attempting to do so.  It seems likely that a regulatory light touch will apply to small UADs safely used for non-commercial purposes.  The more widespread commercial use becomes, the more important it will be to ensure the regulatory framework is fit for purpose.  Countries which achieve this early in the game could gain a considerable competitive advantage.