All sections updated on 20th September 2022.
This information is a guide to airworthiness requirements that is aimed at owners and operators. It summarises but does not replace the requirements detailed elsewhere in regulation, by manufacturers, and in the BGA airworthiness exposition and publications.
‘Airworthy’ means that the glider conforms to the appropriate legal and technical requirements for safe flight.
‘Maintenance’ means any one or combination of the following activities: overhaul, repair, inspection, replacement, modification or defect rectification of an aircraft or component, with the exception of pre-flight inspection.
- Certification and continuing airworthiness – non Part 21 and Part 21 aircraft
- BGA Combined Airworthiness Organisation
- BGA Airworthiness Support
- BGA Inspectors
- Weight and Balance
- Daily Inspections
- Complex Maintenance Tasks
- Maintenance Records
- Aircraft Documents
- Aircraft Parts
- Information for Club Committees
- Detailed Information
Aircraft owners are responsible for the airworthiness of their aircraft.
An aircraft is usually owned by one person, a syndicate of owners, or a club. Depending on how a gliding club is structured, ‘the owner’ of a club aircraft may be the club chairman, or the committee members collectively.
Keeping a glider airworthy physically and legally fit for flight takes effort. Owners should ensure they are familiar with the relevant requirements, the aircraft maintenance programme and the aircraft maintenance manual. Failure to comply with the requirements may invalidate the aircraft insurance.
The owner is responsible for ‘maintenance management’. This includes ensuring:
- the aircraft is maintained in an airworthy condition
- any operational and emergency equipment fitted is correctly installed and serviceable or clearly identified as unserviceable
- the certificate of airworthiness (C of A) is valid (Part 21 aircraft certificates are non-expiring and validated by an Airworthiness Review Certificate (ARC))
- the maintenance of the aircraft is compliant (Part 21 aircraft require a maintenance programme as specified in point Part M Light item MA.302)
- airworthiness directives are complied with
- that any life limited components or inspections are enforced before they run out of life
The owner is responsible for the satisfactory completion of pilot/owner maintenance that they have carried out.
The owner is responsible for ensuring they have the information relevant to the airworthiness of their aircraft.
In a large syndicate, one of the owners should take responsibility for airworthiness management. Information for club committees regarding club aircraft airworthiness management is detailed below at paragraph 12.
More detail for owners
Having an aircraft that is safe to fly does not mean it is legal to fly. To achieve legal compliance for Part 21 and non-Part 21 aircraft, it is necessary to:
- use the correct data and information including the maintenance programme
- use the manufacturers and others airworthiness instructions
- understand who has authority to certify maintenance
- understand how maintenance is recorded and how utilisation is monitored. Several aircraft parts have a legally limited life, eg. Tost release hooks, harnesses, control cables and the airframe itself. The details must be recorded in the aircraft logbook.
Owners need to be familiar with:
Flight Manual and Maintenance Manual. These documents contain valuable information and need to be kept up to date with manufacturer’s amendments. New amendments are often found on manufacturers websites in the Technical Note or Service Bulletins sections.
Maintenance Programme. Part 21 aircraft operated within the BGA airworthiness system use a Self-Declared Maintenance Programme (SDMP). The BGA version is known as the BGA SDMP 267. There is an explanation in the BGA AMP part of the website) that must be customised to an individual aircraft. The customisation must include any type-specific maintenance requirements (a BGA inspector can advise). The BGA SDMP 267 includes an annual inspection that must be certified by a BGA inspector every 12 months. Owners are advised to carefully read and understand the requirement. Non-Part 21 sailplanes use a BGA 267 (the non-SDMP version). Part-ML requires that the SDMP is reviewed annually to ensure it still meets the maintenance requirements for the aircraft type, and the review must be recorded.
Annual inspections. A sailplane must have an annual inspection at least every 12 months. It is not – as the name suggests – just an ‘inspection’. The annual inspection includes a mandatory requirement for maintenance, which includes lubrication and possibly some parts replacement. Under the old Part M the annual inspection could be ‘anticipated’ by up to 90 days without loss, but under current Part ML rules (from 24th March 2020) the annual maintenance cannot be anticipated with loss. Annual maintenance is valid for 12 months from the day the inspector signs the Certificate Release to Service (CRS) on the BGA SDMP 267.
The annual maintenance can be extended by up to 30 days by the owner if required, but only if the ARC is still valid for that extended period. NB, if there are any Airworthiness Directives (ADs) applicable that are actioned by calendar dates or hours due at the annual maintenance, they cannot be extended.
Airworthiness Review Certificate (ARC). An ARC is an audit of a Part 21 aircraft’s paperwork for completeness and compliance. It is a separate activity to the annual maintenance. An ARC is not considered to be maintenance – it is a check of the aircraft’s compliance with the rules. The ARC signatory inspector will additionally review the aircraft for apparent defects that affect airworthiness, that all placards as required by the glider’s flight/maintenance manuals and BGA are fitted. A new ARC is issued every year. An aircraft must not fly if the ARC is not valid.
Pilot / Owner Maintenance. Pilot/owners are permitted to carry out and certify certain maintenance tasks on their aircraft. Details are in the AMPs on the BGA member’s website. Note that a student pilot is not deemed to be a qualified pilot and cannot certify Pilot Owner Maintenance.
It is important that pilot/owners ensure they are competent and aware of the requirements including paperwork requirements before carrying out any maintenance task. If in doubt, seek qualified guidance. In many cases, the services of a qualified inspector are needed. Some BGA inspectors are busy professionals and will quite properly charge a commercial rate. It is up to individual owners and inspectors to consider what service is required and to make their own arrangements, commercial or otherwise.
BGA inspectors. BGA inspectors can be professional or volunteers.
Professional maintainers advertise in ‘Sailplane and Gliding’ magazine, some of whom specialise in repairs. It is up to individual owners and inspectors to consider what service is required and to make their own arrangements. Most clubs have volunteer inspectors. Word of mouth among owners can usually help owners identify local inspectors who can provide the support sought by an owner.
Owners must establish via a BGA Maintenance work order what work they need before works starts (this is a requirement). The BGA does not get involved in commercial issues between parties.
Certificate of Insurance.
It is a legal requirement to hold an appropriate level of insurance. The insurance broker can advise.
The pilot is responsible for the satisfactory completion of the pre-flight inspection. Pre-flight inspection’ means the inspection carried out before flight to ensure that the aircraft is fit for the intended flight. That includes checking there is a valid C of A, ARC and insurance.
The pilot is responsible for the satisfactory completion of pilot/owner maintenance that they have carried out.
2. Certification and continuing airworthiness – non Part 21 and Part 21 aircraft
Non-Part 21 aircraft are essentially those of historic interest and those whose production was stopped before 1 January 1975. Non-Part 21 gliders are certified and maintained under self-regulated elements of the BGA airworthiness system.
Non-Part 21 aeroplanes are certified and maintained under national arrangements as required by the UK ANO.
Part 21 aircraft are certified and maintained under retained EU requirements. The maintenance requirements are defined under the part of the retained regulations known as ‘Part M Light’ (Part-ML).
Part-ML applies to Part 21 sailplanes, tugs and motor gliders. The Part-ML requirements are reflected within the BGA’s airworthiness system.
Non-Part 21 gliders are to:
- Display the BGA number and a BGA recognised unique fin marking.
- Hold a Certificate of Airworthiness (C of A). Issued annually by the BGA (an AMP refers)
- Comply with the maintenance programme. An annual inspection is a fundamental requirement
- Only to be flown if maintained in an airworthy condition.
Visiting, non-BGA non-Part 21 gliders should have a document equivalent to a BGA C of A. Details of the BGA approved procedures for non-Part 21 gliders can be found in the AMP.
Part 21 sailplanes are to:
- Display national registration markings. A fireproof data plate is required. Refer to CAA publication CAP523 with additional guidance in the AMP. A BGA recognised unique fin marking is also required.
- Hold a Certificate of Airworthiness (C of A) or Restricted C of A or Permit to Fly. Part 21 gliders are required to hold a Part 21 Certificate of Airworthiness (where there is still factory product support) or Restricted Certificate (where there is no longer factory product support) or a CAA permit to fly (usually for a new type of glider awaiting full certification). The C of A and restricted C of A are non-expiring once issued. The Permit to Fly must be validated annually.
- Hold an Airworthiness Review Certificate (ARC). A valid ARC is required for flight in a Part 21 aircraft. The ARC is a review of all legal documentation (apart from insurance) including logbooks, certificate of registration, C of A, radio licence, airworthiness directives, lifed items, latest flight manual revision, placards and a brief inspection of the glider. Note that only one day of annual maintenance validity remaining is required to issue an ARC. The ARC is valid for a year. For ARC renewal guidance refer to the AMP.
- Comply with the Maintenance Programme requirements. All gliders operated within the BGA airworthiness system use a Self-Declared Maintenance Programme (SDMP) – see AMP for details. The SDMP includes an annual inspection. Maintenance is subject to ‘Certificate of release to service’ (CRS) through certification by an approved person. In date annual maintenance is required for flight.
- Only to be flown if maintained in an airworthy condition.
Aeroplanes are to;
- Display national registration marking. A fireproof data plate is required. Refer to CAA publication CAP523 with additional guidance in the AMP.
- Hold a Certificate of Airworthiness (C of A) or Restricted C of A or Permit to Fly as appropriate. The C of A and restricted C of A are non-expiring once issued. The permit to fly must be validated annually. For aeroplane airworthiness procedures, please refer to the AMP.
- Hold an Airworthiness Review Certificate (ARC), or if non-Part 21 hold a National ARC (a NARC). Not applicable to Permit to Fly A valid ARC is required for flight in a Part 21 aircraft. The ARC is a review of all legal documentation (apart from insurance) including logbooks, certificate of registration, C of A, radio licence, airworthiness directives, lifed items, latest flight manual revision, placards and a brief inspection of the aeroplane. Note that only one day of annual maintenance validity remaining is required to issue an ARC. The ARC is valid for a year. For ARC renewal guidance refer to the AMP.
- Comply with the Maintenance Programme requirements. Maintenance is subject to ‘Certificate of release to service’ (CRS) through certification by an approved The SDMP includes an annual inspection. Maintenance is subject to ‘Certificate of release to service’ (CRS) through certification by an approved person. In date annual maintenance is required for flight.
- Only to be flown if maintained in an airworthy condition.
3. BGA Combined Airworthiness Organisation
The BGA provides airworthiness support to clubs and owners.
The BGA operates a Combined Airworthiness Organisation (CAO) which supports legally compliant continuing airworthiness and maintenance activity. The BGA holds a CAA-issued Part-CAO approval. The BGA CAO utilises CAA-approved personnel.
The BGA CAO has an Accountable Manager, a Chief Technical Officer (CTO) and a Quality Management Team. Those roles are supported and guided by a small network of volunteer experts including the BGA Technical Committee and Regional Technical Officers.
The responsibilities of the BGA CAO are described in the BGA Combined Airworthiness Exposition (CAE). The BGA CAO requirements are expanded on in the Airworthiness Maintenance Publication (AMP) which comprises individual AMP documents that describe specific topics. To assist owners and operators, the AMP documents are added to or amended from time to time
The BGA CTO publishes a periodic Technical News Sheet (TNS). This publication is aimed at anyone involved with BGA airworthiness and is required reading for BGA Inspectors.
The BGA CAO aims to inform owners by email about important airworthiness information relevant to their aircraft.
4. BGA Airworthiness Support
BGA airworthiness support is a BGA service that includes:
- support from the BGA CAO and personnel
- use of BGA inspectors
- a BGA issued ARC
Renewing the ARC automatically supplies the aircraft with 12 months BGA airworthiness support.
BGA inspectors are not authorised to certify maintenance on the aircraft that do not have a valid BGA issued ARC / valid BGA airworthiness support. Owners of aircraft without a valid BGA issued ARC can apply separately for BGA airworthiness support (which includes the next ARC issue) using the Airworthiness Support Application Form.
5. BGA Inspectors
BGA inspectors are appointed by the BGA based on their demonstrated technical knowledge and experience. BGA inspectors may perform and certify maintenance and repairs (where authorised) to non-Part 21 gliders and Part 21 sailplanes and powered sailplanes, including TMGs, and aeroplanes. Where certifying Part 21 sailplanes, powered sailplanes including TMGs, and aeroplanes, BGA inspectors are required to hold a Part-66L maintenance licence with the relevant privileges. When certifying, inspectors are to provide their signature, name and inspector number.
Information about BGA inspector ratings is available in the BGA Airworthiness and Maintenance Procedures on the BGA website. BGA inspectors operate under the BGA’s airworthiness approvals and airworthiness exposition. For details, including how to become a BGA inspector, please refer to the BGA members website.
6. Weight and Balance
It is critically important that an aircraft Centre of Gravity is kept within the laid down limits. Replacement equipment, repairs and other factors can cause the mass of an aircraft and/or its component parts to change over time. Sailplanes should be weighed at least every 10 years.
Weighing an aircraft is not a simple task and requires calibrated weighing equipment. If in doubt, the advice of an inspector should be sought. Refer to the AMP’s.
Owners are encouraged to seek a copy of the weighing data/report from the inspector or engineer who carried out the weighing.
7. Daily Inspections
Aircraft continuing airworthiness and air operations rules identify that the pilot in command is responsible for the pre-flight inspection, and that this inspection must be carried out by the pilot or another qualified person. BGA Operational Regulations state that “All gliders operated from BGA club sites shall be inspected before flying on each day. Club gliders shall be inspected by club approved persons who must sign that the glider is serviceable before it is flown on that day”.
The requirement to pre-flight inspect aircraft (ie gliders and powered aeroplanes) at BGA clubs is normally achieved by carrying out a Daily Inspection (DI). A DI is a safety critical task. Before carrying out a DI unsupervised, pilots must be trained by a suitably experienced person on how to complete a DI. The club, as the operator, is responsible for qualifying and authorising its members to carry out DIs of its club aircraft. The member pilot’s age, experience and training to carry out DIs should be taken into consideration. Documenting and signing for the DI helps to avoid incorrect assumptions about completing the task.
8. Complex Maintenance
‘Complex maintenance’ (a Part M Light definition) is subject to specific requirements. Before taking on for example a repair, or fabric recovering task, etc, inspectors should refer to the complex maintenance AMP to confirm whether or not the task is deemed to be complex and what specific procedure may be needed.
9. Maintenance Records
All maintenance, servicing, repairs, replacements, and defect rectification must be recorded and certified with the appropriate certificate of release to service and these records form part of the aircraft maintenance records.
Maintenance records should be maintained and retained until at least 2 years after the aircraft has been destroyed or permanently retired from service. The aircraft records stay with the aircraft and the owner has a responsibility to transfer the records to the new owner when sold.
Inspectors have a responsibility to retain their own records for 3 years after the maintenance is completed.
Maintenance records include:
- Scheduled & unscheduled maintenance worksheets and sign-off.
- Defect rectification worksheets
- Test results and records
- Details of any special inspections
- Compliance with Airworthiness Directives (ADs)
- Duplicate inspection record
- Record of flying hours and engine operation (aircraft logbooks)
- Release certificates for parts & materials
- Details of modifications including supplemental type certificates
The approved BGA aircraft logbook is designed to assist owners with compliant and easily managed maintenance records.
10. Aircraft Records
These records should be filed in a suitable folder and in ‘maintenance event’ date order and kept safe and secure from damage or unauthorised interference. This will keep all the documents for a particular aircraft in one place and easy to reference when needed.
Keeping aircraft documents safe is important – it should be noted that replacing documents and certificates can be an expensive and time-consuming task.
11. Aircraft Parts
Clearly it is important that parts fitted to aircraft must be fit for purpose. Aircraft parts are subject to varying levels of conformity requirements. For example:
Fully Released Parts. These are items such as aircraft and engine parts and appliances manufactured in accordance with the aircraft or engine type design specifically for that aircraft or engine type. Also, parts manufactured under Part 21 subpart G or FAA PMA scheme, and TSO, ETSO manufactured parts. These parts are released with either an EASA Form 1 or FAA 8130-3 release certificate or equivalent.
Parts and material released with a Certificate of Conformity. The ‘C of C’ is issued to confirm batch/lot traceability or manufactured in accordance with an approved specification. It can be used for “Standard Parts” ie. items of non-essential equipment and for materials used for the repair or servicing of aircraft. Most aircraft hardware, rubber goods, metal, fabric and other raw materials, liquids and compounds designed for aviation use will be released with a C of C.
Wood used for any structural repair must be graded and certified with a test certificate.
Non-Released Parts. Certain parts may be sourced from commercial suppliers. In many cases these will be OEM or quality pattern parts as originally used in the aircraft construction and may not be available from aviation parts suppliers. Many automotive derived engines are used in powered sailplanes. Some commercially available hardware and small parts are used in the construction of sailplanes generally.
Owners must ensure that they only fit parts that are legally airworthy and only use oils and lubricants that are specified for the application. Fuller information, including examples, is detailed in the AMP.
12. Information for Club Committees
Club fleets tend to be well utilised. They are usually operated and flown by some of the least experienced pilots and can lead hard lives. And in many cases, the gliders are old – K13’s and Pawnees are common examples. Therefore, maintaining club fleets can be quite a challenge. And it’s not just about staying safe. In the event of an accident, one of the first things an insurer will check is whether the glider is compliant with all related requirements.
There are two primary roles involved in ensuring airworthiness compliance of club aircraft:
This would normally be the Chairman of the club or, collectively the Committee of Management. The ‘Owner’ is responsible for ensuring that the aircraft is properly maintained and operated. If the aircraft is leased, the owner’s/operator’s responsibilities should be laid out in the leasing agreement. If the aircraft is privately owned and loaned to the club the responsibility remains with the owner, but the club should satisfy their duty of care.
The Maintenance Manager
A suitable club member should be appointed by the owner to monitor and manage the ongoing airworthiness of the club’s gliders (a maintenance manager). The person who manages the maintenance of a Part 21 aircraft should be separate from the ARC process. The maintenance manager could be the club Technical Officer (or Aircraft Member/Technical Manager) depending on how a club is structured and the positions within the club. The Maintenance Manager carries out the maintenance management function. There are no formal qualifications required for this role, but an owner could be asked during audit to demonstrate who is fulfilling this task.
A suitable system should be established within the club for reporting and managing defects, as well as ensuring that AD’s, lifed items and on condition parts are addressed between ARCs and annual maintenance.
Those pilot members permitted to carry out pilot-owner maintenance on the club fleet should be listed by the club.
The Airworthiness Certificate or Permit to Fly, annual maintenance and insurance validity periods should be made available to everyone who uses the club fleet. A suitable placard is one way of addressing that. Another is to make sure copies of the documents are easily to hand.
It should be made clear to all club pilots who operate the aircraft whether any maintenance is outstanding, or any defects exist that affect the airworthiness of a club aircraft. There are several ways of achieving that including documentation, cockpit warning signs, restricting access to the aircraft, etc.
When planning maintenance, the following points may need to be considered:
- When are the aircraft needed?
- What maintenance is required?
- Who is doing the maintenance and their availability?
- Workshop space and availability
- Arranging for a third party to maintain the aircraft
- Parts and materials
- Cost and budget constraints
An important responsibility for any airworthiness organisation is to carry out quality and oversight audits of aircraft within its responsibility through the BGA Quality Team. The Chief Technical Officer and Regional Technical Officers are there to offer guidance and support to clubs where needed.
Club or private owners may be selected as part of a structured audit plan for an oversight visit or, as the need arises, an unscheduled visit. Please allow access, provide assistance and make the aircraft and its records reasonably available for audit.
The CAA also has a responsibility (as part of their oversight of the BGA) to carry out audits. The CAA can carry out formal site audits and Aircraft Continued Airworthiness Monitoring (ACAM) audits.
These are selected randomly and if a club aircraft is selected, the owner has a legal responsibility to make available the aircraft and its records, including logbooks, maintenance records and certificates as requested at the agreed time and place. The ‘owner’ need not be present, but a representative must be.
An audit can result in a ‘Non-Compliance Notice’ containing findings, which must not be ignored. Findings are classified as either Level 1 or Level 2.
- Level 1 findings must generally be answered before next flight.
- Level 2 findings usually have a limited response time depending on the occurrence
If a club has any difficulties the BGA CTO and RTOs are there to offer guidance. If an owner does not agree with any finding or does not understand it, they should refer to the originator for clarification.
14. Detailed Information
Detailed information is available via the BGA members website Airworthiness webpages.
Details of the names of BGA inspectors in a local area can be obtained from the BGA office.