Basic Principles

Basic principles of Unmanned Aircraft

Unmanned aircraft with an operating mass of 20 kg or less are defined as 'Small Unmanned Aircraft' and according to Article 253 of the ANO 2009 are exempt from the majority of the regulations that are normally applicable to manned aircraft.

Unmanned aircraft with an operating mass of more than 20 kg are subject to regulation as though they are manned aircraft. However, it may be possible to obtain an Exemption from certain regulations with which it is impossible for unmanned aircraft to comply.

Article 166 of the ANO 2009 includes specific regulations for small unmanned aircraft and Article 167 of the ANO 2009 includes additional regulations for small unmanned aircraft that are 'equipped to undertake any form of surveillance or data acquisition'. In summary, they prohibit unmanned aircraft from flying in congested areas, flying close to people or property, flying for aerial work purposes or flying beyond visual line of sight unless permission has been given by the CAA.

Article 138 of the ANO 2009 states that 'a person shall not recklessly or negligently cause or permit an aircraft to endanger any person or property'. This is equally applicable to all manned and unmanned aircraft.

Depending on the design and mass of an unmanned aircraft and the activity for which it will be used, it may be necessary to apply for permission from the CAA before commencing any flight. The table below summarises the requirements:

Aircraft MassAirworthiness Approval?Registration?Operating Permission?Pilot Qualification
20 kg and lessNoNoYes (Note 1)

Yes (Note 1) BNUC-STM or equivalent (Note 2)

More than 20 kg, up to and including 150 kgYes (Note 3)Yes (Note 3)YesYes, BNUCTM or equivalent (Note 2)
More than 150 kgEASA Permit to Fly or UK Permit to Fly in accordance with 'B conditions' (Note 3)YesYesYes, BNUCTM, CPL(A) or equivalent (Note 2)


1) Applicable from 1 January 2010 for aircraft used for Aerial Work purposes or if flown within a congested area and/or close to people or property.

2) Equivalent pilot experience will be considered on a case-by-case basis during application for an operating permission.

3) It may be possible to obtain certain exemptions from the airworthiness and registration requirements.

More detailed information about the requirements for unmanned aircraft operators is contained within CAP 722 Unmanned Aircraft System Operations in UK Airspace - Guidance.