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‘In-sequence’ registration marks

At any given time, there are 75 ‘in-sequence’ registration marks available for new registrations. If you would like to choose from among these firstly please check with Aircraft Registration the ranges available then apply to register the aircraft using the Online CA1 form, on the “Out of Sequence” tab select your choice and the system will reply with availability.

‘Out of sequence’ registration marks – reserving a particular mark

If you are not yet in a position to register an aircraft (see How to Register an Aircraft ) it is possible to reserve out-of-sequence marks in your name for future use for a period of six months. At the end of the six months period the reservation can be renewed if necessary.  Please note that the reservation fee is not deductible from the registration fee once the aircraft itself is registered using the previously reserved marks. 

  • Please see forms and fees for details of how to apply and fees for registration and mark reservation.


Using G-INFO to check the availability of registration marks

You can search for a registration mark on G-INFO, the UK Register database to see if it has already been assigned to an aircraft.

If a mark does not appear on the database it is generally available, but some combinations of letters are not used at all and some marks may be reserved for future use. These non-available marks do not appear on the database but neither are they available for allocation.

After checking the database it is advisable to contact the Aircraft Registration section direct with your requests for availability.

Policy on Combinations of letters which cannot be used

In accordance with ICAO Annex 7, combinations of letters which would cause confusion with distress signals or other urgent signals are not used in registration marks. Examples of marks that cannot be used in either the first three letters or the last three letters of a registration mark are PAN, SOS, TTT and XXX. Any other identified distress signals are also blocked from allocation. Also, to avoid confusion with the three letter combinations beginning with Q used in the “Q Code” system, no marks will be issued which contain the letter Q.

To avoid problems if registration marks are used in telegraphic transmissions the letters ZC are not issued in any part of the registration mark.

Combinations which may be considered offensive may be excluded at the Aircraft Registration Section’s discretion.

Historical, current and de-registered marks not available for re-issue

Any UK registration marks that are currently in use or have been registered in the past are not re-issued to a second aircraft to avoid any confusion. An individual airframe may have more than one registration mark in its lifetime, but a particular registration mark can only apply to one airframe.

Therefore, there are no historical registration marks available for issue (i.e. between G-AAAA and the current in-sequence range) unless it is the original aircraft that is being re-registered or restored to the UK Register. Generally an original aircraft can return to any of the UK registration marks that it has previously carried.

Gliders: BGA trigraphs and registration marks

By default, a glider’s three-letter BGA trigraph will be used as the last three letters of its UK registration mark.

  • The British Gliding Association (BGA) is the recommending organisation for gliding in the UK and they maintain a record of gliders in the UK. The BGA issues a three-letter code for each glider, know as a trigraph.

For example, if the BGA trigraph is PXL the aircraft will be allocated the next available UK registration mark that contains PXL as the last three letters, so if G-CPXL is not available the aircraft will be allocated G-DPXL and so on. Out of sequence registration marks (see above) can also be used on gliders in place of trigraph related marks.

Microlights and minimum lift balloons

There are no longer separate blocks of marks issued to microlights or small light aircraft. These aircraft are now entered in the main in-sequence blocks or given out-of-sequence marks if requested.

However, minimum lift balloons are confined to the G-FYAA-ZZ blocks.

News from UK Civil Aviation Authority

  1. Regulator signs working arrangement with Japan
  2. Plans to upgrade airspace unveiled by UK regulator
  3. Regulator Board hosted a stakeholder meet-and-greet at Farnborough Airshow