Equipment used in aircraft may be eligible for a stand-alone approval or ‘authorisation’. These authorisations do not constitute an approval to install on an aircraft, but credit may be claimed from the equipment authorisation towards the showing of compliance with the aircraft Certification Specifications (CS) when certificating its installation.
The equipment approvals issued by the Civil Aviation Authority (CAA) using Certification Specifications European Technical Standard Order (CS-ETSO) are UK Technical Standard Order Authorisations (UKTSOAs).
The UKTSOA is granted in accordance with UK Regulation (EU) No 748/2012, Part 21 Subpart O when the manufacturer (Applicant) can demonstrate to the CAA that the equipment meets a prescribed Minimum Operational Performance Specification (MOPS). The MOPS acceptable to the CAA include those within or referenced from CS-ETSO. Further information about UKTSOA’s can be found on the CAA website.
The CAA also issued a small number of Equipment Approvals after the formation of EASA and prior to the UK’s withdrawal from the European Union (EU). These approvals are valid only for use on aircraft registered in the UK.
United Kingdom Technical Standard Order (UKTSO) Authorisations
United Kingdom Technical Standard Order (UKTSO) Authorisations issued by the Civil Aviation Authority (CAA) will be prefixed with UK.TSOA.XXXXX
European Technical Standard Order (ETSO) Authorisations (European approval)
European Technical Standard Order (ETSO) Authorisations (European approval) that were issued by EASA prior to the UK’s withdrawal from the European Union (EU) were prefixed with one of the following:
EASA.21O. (ETSO Authorisation)
- This is an Authorisation (approval) issued for an EU manufactured piece of equipment.
EASA.IM.21O. (ETSO Authorisation for Import)
- This is an Authorisation (approval) issued to a manufacturer from a non-EU Member State. In addition, before EASA could issue an ETSO Authorisation for Import (under Part 21, Subpart O), EASA must have an 'Arrangement' with the exporting Authority.
The EASA website offers more general information and a complete listing of ETSO Authorisations (issued).
Joint Technical Standard Order (JTSO) Authorisations (European approval)
Joint Technical Standard Order (JTSO) Authorisations that were issued by the UK Civil Aviation Authority (CAA) are prefixed with one of the following:
CAA.O. (JTSO Authorisation)
- This is an Authorisation (approval) issued for a UK manufactured piece of equipment, which complies with JAR-21, Subpart O and the relevant JTSO Standard (JAR-TSO).
CAA.N-O. (JTSO Authorisation for Import)
- This is an Authorisation (approval) issued to a manufacturer from a non-Joint Aviation Authorities (JAA) Member State, which complies with JAR-21, Sub-subpart N-O and the relevant JTSO Standard.
In addition, before a JAA Authority could issue a JTSO Authorisation for Import (under JAR-21 Sub-subpart N-O), the JAA must have had an 'Arrangement' with the exporting Authority (as required by JAR 21N5). The UK CAA had such an Arrangement with the following non-JAA exporting Authority:
- Federal Aviation Administration (FAA) in the United States of America.
The JAA Website offers more general information and a complete listing of JTSO Authorisations (issued).
There are currently five other National Aviation Authorities (NAAs) within the JAA which are able to issue JTSO Authorisations. Country and approval number prefixes are as follows:
- Austria - 'ACG'
- France - ‘F'
- Germany - ‘LBA'
- Italy - ‘ENAC'
- Sweden - 'LFV'
Aircraft equipment approved in the United Kingdom now supported under Grandfather Rights, falls into the following categories indicated by the approval numbers prefixed by the following letters;
Please note that while historic equipment approvals are still valid, it is the responsibility of the installer / operator to ensure that any equipment installed meets the operational requirements applicable to the aircraft and type of operation. Equipment must only be installed in accordance with an approved change.
British Civil Airworthiness Requirements (UK national approval)
Radio Equipment
WR (Wireless Receiver)
Equipment manufactured in the United Kingdom approved for use in any UK registered civil aircraft. Applicants must have demonstrated compliance with British Civil Airworthiness Requirements (BCAR), chapter A4-10 (CAP553). This category may also be used for equipment manufactured outside the United Kingdom, where the manufacturer is or was a Civil Aviation Authority (CAA) approved organisation.
VC (Validation Certification)
Equipment manufactured in countries other than the United Kingdom or ex-military equipment approved for use in any UK registered civil aircraft. Applicants must have demonstrated compliance with BCAR B4-10.
LA (Light Aircraft)
The prefix LA is followed by the Class in which the equipment was approved. 'LA1' for Class 1 and 'LA3' for Class 3.
Class 1 equipment is without operational restrictions and may be used for Visual Flight Rules (VFR) and Instrument Flight Rules (IFR) flight in any airspace, provided that it has adequate frequency coverage and number of channels for the particular area in which the aircraft is to operate. It may also be used for any of the purposes specified for Class 3.
Class 3 communication equipment may be used outside controlled airspace under VFR and IFR, to communicate with airfield Air Traffic Control (ATC)s where it is not a condition of use of the airfield that Radio Transmission (R/T) equipment be carried, or for communication with the Flight Information Region Controller. It may also be used within controlled airspace under special VFR or under Special entry/exit lane procedures. Class 3 navigation equipment may only be used outside controlled airspace under VFR or IFR, or 'Special VFR' within controlled airspace.
Please be aware for equipment installed in aircraft not exceeding 5700kg
G (Glider)
Equipment for use in any motorless aircraft, self-launching or self-sustaining gliders.
This may generally be interpreted to include balloons, hang gliders, microlights and other sporting and recreational aeronautical communications.
Please be aware for equipment installed in aircraft not exceeding 5700kg
MIS (Miscellaneous)
Non-flight operational radio equipment. Such approvals may be subject to limitations on operational usage and may apply to individual applicants and specific aircraft only.
Airframe Parts and Equipment
E (Equipment)
An 'E' approval was granted for equipment (other than radio apparatus) to UK Manufacturers. Applicants must have demonstrated compliance with BCAR A4-8.
AR (Appliance Registration)
An 'AR' approval was granted for equipment (other than radio apparatus) to non-UK Manufacturers. Applicants must have demonstrated compliance with BCAR B4-8.
SA (Safety Acceptance)
A 'SA' approval was issued when it has been shown that the equipment presents no hazard to an aircraft.
It should be noted that Safety Acceptance of cabin service equipment by the Civil Aviation Authority (CAA) does not imply acceptance of the item's performance, efficiency or its serviceability.
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