10.5 Certification

Question 1

Part 21

UK Regulation (EU) No 748/2012 - Laying down implementing rules for the airworthiness and environmental certification of aircraft and related products, parts, and appliances, as well as for the certification of design and production organisations.

Answer 1

This regulation applies to all aircraft registered in the UK, as well as to all products, parts, and appliances used in those aircraft. It establishes the procedures and requirements for the issuance of certificates of airworthiness, approvals of design changes, and production organisations, among other things. Compliance with Part-21 is mandatory for any organisation or individual involved in the design, production, maintenance, or operation of aircraft and related products, parts, and appliances in the UK

Question 2

Part 21 UK Regulation (EU) No 748/2012

Annex I is split into Section A and Section B. Section A covers requirements for applicants and section B covers procedures for the CAA. Part-21 is divided into several Subparts, each addressing different aspects of the certification process.

Answer 2

Annex II contains Repealed Regulation with alist of its successive amendments.

Annex III a correlation table between EU regulation and the UKCAA ones.

Question 3

Implementing Rules (IR) are binding in their entirety and used to specify a high and uniform level of safety and uniform conformity and compliance. The IRs are adopted by the CAA in the form of regulations.

Question 4

Acceptable Means of Compliance (AMC) are non-binding. The AMC serves as a means by which the requirements contained in the basic regulation, and the IR, can be met. However, applicants can decide to show compliance with the requirements using other means. Both the CAA and organisations can propose alternative means of compliance.

Answer 4

Alternative Means of Compliance” are those that propose an alternative to an existing AMC. Those Alternative Means of Compliance proposals must be accompanied by evidence of their ability to meet the intent of the IR. The use of an existing AMC gives the user the benefit of compliance with the IR.

Question 5

Certification Specifications (CS) are non-binding technical standards adopted by the CAA to meet the essential requirements of the basic regulation. CSs are used to establish the Certification Basis (CB)

Question 6

An airworthiness directive means a document issued or adopted by the CAA which mandates actions to be performed on an aircraft to restore an acceptable level of safety

The CAA shall issue an airworthiness directive when

Answer 6

an unsafe condition has been determined by the CAA to exist in an aircraft, as a result of a deficiency in the aircraft, or an engine, propeller, part or appliance installed on this aircraft; and

that condition is likely to exist or develop in other aircraft.

Question 7

United Kingdom Technical Standard Order (UKTSO)

Question 8

An airworthiness directive shall contain at least the following information

Answer 8

an identification of the unsafe condition;
an identification of the affected aircraft;
the action(s) required;
the compliance time for the required action(s);
the date of entry into force.

Question 9

All Design Organisations shall collaborate with the Production Organisation as necessary to ensure

Answer 9

the satisfactory coordination of design and production

the proper support of the continued airworthiness of the product, part or appliance.

Question 10

A Type Certificate (TC) is awarded to the manufacturer of an aircraft, engine or propeller by the CAA. In the case of EU Member States, it shall be EASA.

Question 11

There are 3 different categories of Type Certificate

Type Certificate (TC)

Restricted Type Certificate (RTC)

Supplemental Type Certificate (STC)

Answer 11

The certificate constitutes a statement that the design of the aircraft has been approved by the CAA and meets the applicable Certification Specification (CS) standards.

The CAA will evaluate the design, flight testing and previous service experience of the aircraft type

Question 12

Any organisation applying for a type certificate or restricted type certificate shall demonstrate its capability by holding a design organisation approval

Answer 12

An applicant for a type-certificate or restricted type-certificate shall demonstrate its capability by holding a design organisation approval, issued by the CAA in accordance with Subpart J.

Question 13

A Supplemental Type Certificate (STC) is issued by the CAA approving a product (aircraft, engine, or propeller) major modification by another Design Organisation (not the original Type Certificate Holder (TCH)). The STC defines the product design change, states how the modification affects the existing type design, and lists serial number effectivity.

Question 14

In order to be issued a product type certificate or, when the aircraft does not meet the essential requirements, an aircraft restricted type certificate, the applicant shall

Answer 14

demonstrate its capability by holding a design organisation approval;

demonstrate compliance with the applicable Type Certification basis and environmental protection requirements;

demonstrate that the engine and propeller, if installed in the aircraft:

have a type-certificate issued or determined in accordance with this Regulation; or

have been demonstrated to be in compliance with the aircraft type-certification basis established and the environmental protection requirements designated and notified by the CAA as necessary to ensure the safe flight of the aircraft.

Question 15

Type Certificate Data Sheet (TCDS) associated with each Type Certificate or Restricted type certificate. TCDS records the basis of certification, the designation of each approved variant and general information concerning the design

Question 16

A Type Certificate and Restricted Type Certificate shall be issued for an unlimited duration. They shall remain valid subject to:

Answer 16

The holder remaining in compliance with this Annex 1 (Part-21); and

The certificate not being surrendered or revoked under the applicable administrative procedures established by the CAA.

Upon surrender or revocation, the Type Certificate and Restricted Type Certificate shall be returned to the CAA.

Question 17

Changes to a type-certificate are classified as minor and major. A ‘minor change’ has no appreciable effect on the mass, balance, structural strength, reliability, operational characteristics, operational suitability data, or other characteristics affecting the airworthiness of the product or its environmental characteristics.

Answer 17

Only the type-certificate holder may apply for approval of a major change to a type-certificate under this Subpart; all other applicants for a major change to a type-certificate shall apply under Subpart E (Supplemental Type Certification).
Any natural or legal person may apply for approval of a minor change to a type-certificate under this Subpart.

Question 18

Minor changes in a type design shall be classified and approved either:

By the CAA; or
By an appropriately approved design organisation under a procedure agreed with the CAA.

Answer 18

Major changes to a type-certificate shall be classified and approved by:
the CAA; or

an approved design organisation within the scope of its privileges provided in the terms of approval.

Question 19

Part-21 Subpart G details the requirements to be met by an organisation wishing to be granted POA. The process is similar to that described for Part-145 Maintenance Organisation. It is granted by the CAA where a designated team is assigned to the process.

Answer 19

The applying organisation is required to draft an exposition explaining how it will meet the requirements, the requirements include:

A Quality System.
An Occurrence Reporting System.
Allowing the competent authority access at any time.

Question 20

Each application for an agreement to the showing of conformity of individual products, parts and appliances under this Subpart shall be made in a form and manner established by the competent authority.
Such application shall contain:
evidence which demonstrates, where applicable, that:

Answer 20

production organisation approval under Subpart G would be inappropriate; or
the certification or approval of a product, part or appliance under this Subpart is needed pending the issuance of a production organisation approval under Subpart G

Provided a manual that contains:

Description of the production inspection system.
Description of the means for making the determination of the production inspection system.
Description of the tests required for product approval.
Names of persons authorised for raising the Statement of Conformity.

Question 21

Production Organisation Approval (POA)

Part-21 Subpart G details the requirements to be met by an organisation wishing to be granted POA. The process is similar to that described for Part-145 Maintenance Organisation. It is granted by the CAA where a designated team is assigned to the process.

Answer 21

The applying organisation is required to draft an exposition explaining how it will meet the requirements, the requirements include:

A Quality System.
An Occurrence Reporting System.
Allowing the competent authority access at any time.

Question 22

Subpart K - Parts and Appliances

Answer 22

The showing of compliance of parts and appliances to be installed in a type-certificated product shall be made:

in conjunction with the type-certification procedures of Subpart B, D or E for the product in which it is to be installed; or
where applicable, under the UKTSO authorisation procedures of Subpart O; or
in the case of standard parts, in accordance with officially recognised Standards

Question 23

standard repairs are repairs:
in relation to:
aeroplanes of 5 700 kg Maximum Take-Off Mass (MTOM) or less;
rotorcraft of 3 175 kg MTOM or less;
sailplanes and powered sailplanes, balloons and airships as defined in ELA1 or ELA2

Question 24

PART 21

Subpart O - United Kingdom Technical Standard Order Authorisations

Answer 24

This part covers how to obtain design organisation approval (DOA) and Production Organisation Approval (POA) of parts and appliances fitted to products (Aircraft, Engines and Propellers). It is very similar to the approval for DOA and POA for products and is expanded on in CS-UKTSO

Question 25

CS-ETSOs has two parts:

Answer 25

Index 1 lists all UKTSO which are technically similar to FAA-TSO Index 2 lists all UKTSO which are not technically similar to FAA-TSO

Question 26

Subpart Q - Identification of Products and Parts

Answer 26

The identification of products shall include the following information: the manufacturer’s name; product designation; the manufacturer’s serial number; any other information the CAA finds appropriate. Aircraft and Engines shall use a fireproof plate to contain the information above. The ID plate shall be secured to enable it to be accessible and legible and will not likely be defaced or removed during normal service or destroyed in an accident.

Question 27

Propellers, propeller blades and propeller hubs will be identified using a plate, stamping, etching or other approved method of fireproof identification. The identification will be placed on a non-critical surface.

Answer 27

For manned balloons, the identification plate prescribed in point (b) shall be secured to the balloon envelope and shall be located, if practicable, where it is legible to the operator when the balloon is inflated.

Question 28

CS-23 - Normal-Category Aeroplanes are the most common type of aeroplanes and are typically used for general aviation and small commercial operations. Applies to aeroplanes with a passenger seating configuration of 19 or less and a maximum certified take-off mass of 8 618 kg (19 000 pounds) or less. There are various levels depending on seating capacity and performance.

Answer 28

CS 25 - Large Aeroplanes CS 27 - Small Rotorcraft applies to rotorcraft with a maximum weight of 3 175 kg (7 000 lbs) or less and nine or less passenger seats. CS 29 - Large Rotorcraft maximum weight greater than 9072 kg (20 000 pounds) and 10 or more passenger seats must be type certificated as Category A rotorcraft. Rotorcraft with a maximum weight greater than 9072 kg (20 000 pounds) and nine or less passenger seats may be type certificated as Category B rotorcraft provided it meets the CS-29 requirements

Question 29

As a result of the UK leaving the EU, and because the CAA is no longer a member of EASA, the CAA has taken on State of Design responsibilities from EASA for products where the UK is State of Design. The CAA is now responsible for fulfilling the UK’s obligations as State of Design or Manufacture specified in Part II of Annex 8 – “Airworthiness of Aircraft” to the Convention on International Civil Aviation.

Answer 29

Through the EU (Withdrawal) Act 2018, and a number of statutory instruments, all EU aviation law in force and applicable up to 31 December 2020 has been retained in UK domestic law. Hence these aviation regulations continue to apply to all Part 21 products, whether or not the UK is State of Design. Non-Part 21 products (i.e. that fall within the categories set out in Annex I of Regulation (EU) 2018/1139) continue to be the responsibility of the UK CAA. Lists of Part 21 products where the UK is the State of Design are provided in Mandatory Requirements for Airworthiness (CAP 747) Section 1 Part 4.

Question 30

A Certificate of Airworthiness (C of A) is the internationally recognised document certifying an aircraft’s suitability to enter service. It is a requirement of the ICAO and is issued by the UK CAA to an individual aircraft. The aircraft’s Flight Manual (produced by the manufacturer) is also covered by the certification and forms part of the (C of A).

Question 31

For an aircraft to be allowed to fly, the aircraft must have a current and valid:

Answer 31

Certificate of Airworthiness, or a Restricted Certificate of Airworthiness, or a Permit to Fly.

Question 32

Aircraft that meet the applicable type design standard and are in a condition for safe operation are eligible for the issue of a Certificate of Airworthiness (C of A).

Question 33

Aircraft type design requirements and their associated Certificates of Airworthiness fall into two main categories

Answer 33

Part 21 aircraft non-Part 21 aircraft. Historically non-Part 21 aircraft are sometimes referred to as national aircraft

Question 34

Part 21 aircraft - Aircraft in this category are those that were previously managed by the European Union Aviation Safety Agency (EASA) and were considered as EASA types. These are regulated under UK Regulation (EU) 2018/1139 (known as the UK Basic Regulation) and its implementing regulations covering airworthiness, operations, flight crew licensing, etc. regardless of their State of Design or State of Manufacture

Answer 34

Non-Part 21 - Aircraft in this category are managed nationally under the UK Air Navigation Order. Airworthiness requirements for these aircraft are set out in the provisions of British Civil Airworthiness Requirements (BCAR). These aircraft, used for State purposes, are those included within the scope of the UK Air Navigation Order (e.g. military, customs, police, search and rescue, firefighting, border control, coastguard aircraft).

Question 35

Certificate of Airworthiness issue refers to the first issue of a UK C of A to the aircraft. The term C of A Subsequent Issue is applicable when one of the criteria below is met:

Answer 35

The previous UK C of A has been revoked or surrendered. The aircraft held a UK C of A prior to being exported to another State and has since returned to the UK Register. The aircraft was removed from, and has since been re-registered on, the UK Register. The aircraft has remained on the UK register and the (C of A) has expired, and a non-expiring (C of A) has not yet been issued.

Question 36

Certificates of Airworthiness are non-expiring and require a valid Airworthiness Review Certificate in order to operate under the provisions of the (C of A)

Answer 36

airworthiness review A 12-monthly review which entails a full documented review of the aircraft records and a physical survey of the aircraft.

Question 37

To be classified as Non-Part 21, an aircraft has to meet one or more of the following criteria:

Answer 37

Manned aircraft set out in UK Basic Regulation Annex I (known as ‘Annex I aircraft’): Historic aircraft meeting the following criteria: Aircraft whose: initial design was established before 1 January 1955, and production has been stopped before 1 January 1975; ii. Aircraft having a clear historical relevance, related to: A participation in a noteworthy historical event, A major step in the development of aviation, or, A major role played into the armed forces of a State;

Question 38

To be classified as Non-Part 21, an aircraft has to meet one or more of the following criteria:

Answer 38

Aircraft specifically designed or modified for research, experimental or scientific purposes, and likely to be produced in very limited numbers; Aircraft that have been in the service of military forces, unless the aircraft is of a type for which a design standard has been adopted by the UK CAA; Aeroplanes having measurable stall speed or the minimum steady flight speed in landing configuration not exceeding 35 knots calibrated air speed (CAS), Aircraft, including those supplied in kit form, where at least 51% of the fabrication and assembly tasks are performed by an amateur, or a non-profit making association of amateurs, for their own purposes and without any commercial objective

Question 39

Restricted Certificate of Airworthiness Under the current Part-21 regulation an orphaned aircraft cannot be issued a Certificate of Airworthiness, which requires that a Type Certificate (TC) holder takes responsibility for the continued oversight of the design.

Answer 39

They can therefore only continue to be operated if they hold a Restricted Certificate of Airworthiness or a Permit to Fly. These documents can only be issued on the basis of a design approved by the UK CAA

Question 40

An aircraft is deemed orphaned when

Answer 40

The legal person holding the TC has ceased to exist. The TC automatically becomes invalid by law because there is no one to be in compliance with the TC holder's responsibilities The TC holder no longer complies with his regulatory obligations

Question 41

An aircraft is deemed orphaned when Typical cases of this

Answer 41

The TC holder loses their Design Organisation Approval (DOA) or fails to comply with 21.A.174. (showing of compliance) The TC holder has surrendered the TC

Question 42

In addition to orphaned aircraft, a Restricted (C of A) could also be issued to an aircraft that has not fully met the requirements but qualifies for a Restricted CoA, or an aircraft used for crop spraying whilst the equipment is fitted may only be able to operate under a restricted CoA.

Question 43

The CAA shall issue a restricted certificate of airworthiness for:

Answer 43

new aircraft: upon presentation of the documentation required by point 21.A.174(b)(2); when the CAA is satisfied that the aircraft conforms to a design approved by the CAA under a restricted type-certificate or in accordance with specific airworthiness specifications, and is in a condition for safe operation

Question 44

The CAA shall issue a restricted certificate of airworthiness for:

Answer 44

used aircraft: upon presentation of the documentation required by point 21.A.174(b)(3) demonstrating that: the aircraft conforms to a design approved by the Agency under a restricted type-certificate or in accordance with specific airworthiness specifications and any supplemental type-certificate change or repair approved in accordance with this Annex I (Part 21); and the applicable airworthiness directives have been complied with; and the aircraft has been inspected in accordance with the provisions of Annex I (Part-M) or Annex Vb (Part-ML) of Regulation (EU) No 1321/2014, as appropriate;

Question 45

For an aircraft that cannot comply with the essential requirements referred to in Regulation (EC) No 216/2008 and which is not eligible for a restricted type-certificate, the CAA shall, as necessary to take account of deviations from these essential requirements:

Answer 45

issue and check compliance with specific airworthiness specifications ensuring adequate safety with regard to the intended use, and specify limitations for use of this aircraft.

Question 46

All UK CAA aircraft that are not in possession of a valid Airworthiness Certificate or Restricted Airworthiness Certificate will fly under a Permit to Fly that is approved either by the UK CAA or a Part-21 Organisation that has approval to raise Permits to Fly.

Answer 46

For example, as the result of damage, or when a Certificate of Airworthiness cannot be issued due to the aircraft not complying with the essential requirements for airworthiness or when compliance with those requirements has not yet been shown, but the aircraft is nevertheless capable of performing a safe flight.

Question 47

Any natural or legal person shall be eligible as an applicant for a permit to fly except for a permit to fly requested for the purpose of point 21.A.701(a)(15) where the applicant shall be the owner. (b) Any natural or legal person shall be eligible for application for the approval of the flight conditions.

Question 48

The applicant for a permit to fly may be a person other than the registered owner of the aircraft. As the holder of this permit will be responsible for ensuring that all the conditions and limitations associated with the permit to fly are continuously satisfied, the applicant for the permit should be a person or organisation suitable for assuming these responsibilities.

Question 49

permit to fly may be issued by the CAA after presentation of the required data, when the flight conditions have been approved and if required any CAA inspections are complete. An approved design organisation, with the privilege to do so, may issue a permit to fly when the flight conditions have been approved. An approved CAMO or CAO with the privilege to do so, may also issue a permit to fly when the flight conditions have been approved.

Answer 49

The permit to fly shall specify the purpose(s) and any conditions and restrictions which have been approved. For permits issued under points (b) & (c), a copy of the permit to fly and associated flight conditions shall be submitted to the CAA at the earliest opportunity but not later than 3 days. Upon evidence that any of the conditions specified in point 21.A.723(a) are not met the organisation shall immediately revoke that permit to fly and inform the CAA without delay.

Question 50

A permit to fly is not transferable. Notwithstanding point (a), for a permit to fly issued for the purpose for non-commercial flying activity on individual non-complex aircraft or types for which a certificate of airworthiness or restricted certificate of airworthiness is not appropriate and where ownership of an aircraft has changed, the permit to fly shall be transferred together with the aircraft.

Question 51

A permit to fly shall be issued for a maximum of 12 months and shall remain valid subject to compliance with all the following conditions

Answer 51

the organisation continues to comply with the conditions and any restrictions associated with the permit to fly; the holder, and its suppliers or subcontractors as appropriate, acknowledge that the CAA may carry out investigations; the permit to fly has not been revoked by the CAA or surrendered by its holder; the aircraft remaining on the same register.

Question 52

The first use of aircraft registrations was based on the radio call signs allocated at the London International Radiotelegraphic Conference in 1913

Question 53

It is mandatory that all UK Part-21 aircraft must be registered with the UK CAA and they must carry proof of this registration in the form of a legal document called a Certificate of Registration at all times.

Answer 53

The Certificate Of Registration (COR) also details the aircraft's serial number and the owner's name. The COR has no expiry date but is only valid until there is a change of ownership of the aircraft or until the aircraft is destroyed or permanently withdrawn from service. An aircraft can only be registered in one country and can only have one COR. If the aircraft is sold abroad, then the COR must be returned to the issuing NAA before it can be registered in the new country

Question 54

Nationality and Registration Marks An aircraft registration is a unique alphanumeric code that identifies a civil aircraft, similar to a licence plate on a car

Answer 54

Registration markings are normally positioned on the fuselage and wings but occasionally it can also be on the tail. Depending on the country of registration, this suffix is a numeric or alphanumeric code and consists of one to five digits or characters respectively. UK registered aircraft use a capital letter ‘G’ followed by a group of four letters.

Question 55

Wing registration markings must be 500 mm in height and fuselage registration markings must be 300 mm in height.

Answer 55

A fireproof plate with all the aircraft details must be positioned in a prominent place for the purposes of post‑fire or post‑crash accident investigation

Question 56

An ellipsis in square brackets [...] indicates that text has been intentionally left out, such as the result of an earlier amendment to the regulation, AMC, GM or CS.

Question 57

The Noise Certificate is a document issued by the UK CAA according to the procedures described in Part 21, Sub-part I, to each aircraft registered in the UK to which the noise certification regulations apply. The certificate attests the noise certification status of the aircraft to which it is issued. The certificate’s format and the information it contains is consistent with ICAO Annex 16.

Question 58

not every aircraft on the UK Register is obliged to have a Noise Certificate. For example there is no legislation requiring Noise Certificates for Permit to Fly aircraft and some older aircraft. Note also that microlight aeroplanes are now exempt from the need to be issued with a Noise Certificate (Official Record Series 4, No. 1502).

Question 59

A Noise Certificate is issued for an unlimited duration subject to the limitations described in Part 21 21.A.211 of Regulation No 748/2012. You will need to apply for a new Noise Certificate in the following cases

Answer 59

If the aircraft’s registration mark changes. If there is any change to the aircraft’s configuration that affects the aircraft’s noise characteristics (e.g. MTOW/MLW or a change to the aircraft’s engines and/or propellers). If it is discovered that any of the details entered on the Noise Certificate are not correct for the aircraft to which it was issued.

Question 60

You will not need to apply for a new Noise Certificate in the following cases:

Answer 60

When the aircraft is transferred from one UK operator/owner to another UK operator/owner and retains the same registration mark. If the noise record in the databases against which the certificate was issued is revised. Although not required, you may request that a new Noise Certificate be issued against the revised record.

Question 61

Aircraft noise certification levels approved by EASA up to and including 31 December 2020 are considered to be also approved by UK CAA. Noise certification levels approved by EASA since then are not automatically approved by UK CAA.

Question 62

Noise legislation The world's noisiest airliners are effectively banned from UK airports. Any subsonic jet aeroplane that has either a maximum take-off mass of 34,000kg or more, or more than 19 passenger seats must meet the ICAO noise standards set out in annex 16.

Answer 62

Exemptions The CAA can grant temporary exemptions from these requirements to specific flights, but only in very specific circumstances. Exemptions may be granted where the CAA is satisfied: that the operations of the aeroplane are of such an exceptional nature that it would be unreasonable to withhold an exemption (for example urgent relief flights, official visits by Heads of State); or that the aeroplane is being operated on a non-revenue flight for the purposes of alterations, repair or maintenance. The CAA will also consider applications for exemptions in relation to aeroplanes of historical interest.

Question 63

Where ownership of an aircraft has changed and it remains on the United Kingdom register, the noise certificate must be transferred together with the aircraft.

Answer 63

The holder of the noise certificate shall provide access to the aircraft for which that noise certificate has been issued upon request by the CAA .

Question 64

A noise certificate shall be issued for an unlimited duration. It shall remain valid subject to: .

Answer 64

compliance with the applicable type-design, environmental protection and continuing airworthiness requirements; and the aircraft remaining on the same register; and the type-certificate or restricted type-certificate under which it is issued not being previously invalidated under point 21.A.51; the certificate having not been revoked by the CAA or surrendered by the certificate holder

Question 65

You will not need to apply for a new Noise Certificate in the following cases:

Answer 65

When the aircraft is transferred from one UK operator/owner to another UK operator/owner and retains the same registration mark. If the noise record in the databases against which the certificate was issued is revised. Although not required, you may request that a new Noise Certificate be issued against the revised record

Question 66

All operators must produce a Weight & Balance Schedule. This document will include all the information that may be used to prepare a load sheet for each flight. The schedule will include details of the basic weight of the aircraft and also weights of all the items that may be added to the aircraft for specific flights. It will also detail the position of the datum from which moments are calculated and the moment arms for each item that may be added. The schedule is unique for a particular aircraft.

Answer 66

An operator shall ensure that during any phase of operation, the loading, mass and centre of gravity of the aircraft complies with the limitations specified in the approved Aeroplane Flight Manual, or the Operations Manual if more restrictive. must establish the mass and centre of gravity of any aircraft by actual weighing prior to entry into service and thereafter at intervals of 4 years, if individual aircraft masses are used and 9 years if fleet masses are used must determine the mass of all operating items and crew members include in the aircraft dry operating mass by using standard masses. The influence of their position on the aircraft centre of gravity must be determined. must establish the mass of the traffic load, including any ballast, by actual weighing or determine the mass of the traffic load in accordance with standard passenger and baggage masses. must determine the mass of the fuel load by using the actual density or, if not known, the density calculated in accordance with a method specified in the Operations Manual

Question 67

weight and balance This specifies that an operator shall establish mass and balance documentation prior to each flight, specifying the load and distribution. The mass and balance documentation must enable the commander to determine that the load and it’s distribution is such that the balance limits of the aircraft are not exceeded.

Question 68

Weighing of an Aircraft New aircraft that have been weighed at the factory may be placed into operation without reweighing if the mass and balance records have been adjusted for alterations or modifications to the aircraft.

Answer 68

. Aircraft transferred from one UK operator to another UK operator do not have to be weighed prior to use by the receiving operator, unless more than 4 years have elapsed since the last weighing.

Question 69

The mass and centre of gravity (C of G) position of an aircraft should be revised whenever the cumulative changes to the dry operating mass exceed ±0.5 % of the maximum landing mass or for aeroplanes the cumulative change in C of G position exceeds 0.5 % of the mean aerodynamic chord. This may be done by weighing the aircraft or by calculation.

Question 70

Moment =

Answer 70

Mass x horizontal distance from datum.

Question 71

Traffic Load =

Answer 71

Total mass of passengers, baggage, cargo, specialist equipment and ballast.

Question 72

Dry Operating Mass

Answer 72

Total mass excluding fuel and traffic load.

Question 73

Percentage Mean Aerodynamic Chord (% MAC)

Answer 73

Mean Aerodynamic Chord or MAC is the average length of the wing chord, in large aircraft centre of gravity limitations and the actual centre of gravity are often expressed in terms of % MAC.

Question 74

For a group of aeroplanes of the same model and configuration, an average dry operating mass and C of G position may be used as the fleet mass and C of G position, provided that

Answer 74

the dry operating mass of an individual aeroplane does not differ by more than ±0.5 % of the maximum structural landing mass from the established dry operating fleet mass; or the C of G position of an individual aeroplane does not differ by more than ±0.5 % of the mean aerodynamic chord from the established fleet C of G. the operator should verify that, after an equipment or configuration change or after weighing, the aeroplane falls within the tolerances above.

Question 75

To add an aeroplane to a fleet operated with fleet values, the operator should verify by weighing or calculation that it’s actual values fall within the tolerances.

Question 76

The CAA had previously been issuing radio licences to the aviation sector for a number of years on behalf of Ofcom. All Aeronautical Radio Licences are now issued and administered by Ofcom and not the Civil Aviation Authority. The CAA will continue to issue frequency assignments and Air Navigation Order (ANO) safety approvals as normal.

Question 77

The requirement for a radio licence originates from the International Telecommunication Union (ITU), an international organisation responsible for managing the allocation of radio frequencies. They are also responsible for regulating the use of transmitting equipment to ensure they operate within acceptable tolerances.

Answer 77

Installation of new radio equipment will be carried out as a major modification and will require approval by the CAA following successful ground and flight testing. On successful completion the aircraft will again be awarded with a Certificate of Approval of Radio installation

Question 78

The ICAO does not provide a detailed listing of equipment to be mentioned on a radio licence. However, all transmitting radio equipment for communication and navigation (VHF, HF, ELT, radar, etc.) installed on an aircraft should be listed in the radio licence.

Question 79

Radio equipment use and airworthiness Equipment shall comply with the necessary enforceable airworthiness directives and regulations issued by the:

Answer 79

Civil Aviation Authority (CAA) European Aviation Safety Agency (EASA) Federal Aviation Administration (FAA)

Question 80

Radio equipment is approved through the manufacturing process but the aircraft has to also go through an “approval of installation”. This is normally carried out by the aircraft manufacturer during the certification process of the aircraft

Answer 80

when the installation has passed all its testing it will be awarded a “Certificate of Approval of Radio installation”. When the aircraft is delivered to the customer the owner can then apply for his radio licence.

Question 81

if an aircraft is in service (post Type Certification) and the owner wants to install new radio equipment it will have to be carried out under a major modification to seek approval based on a Survey by the CAA followed by ground and flight testing to prove satisfactory functioning. When this process is successfully completed the aircraft will again be awarded with a “Certificate of Approval of Radio installation”

Question 82

Radio License The CAA no longer issue licences on behalf of OFCOM and all owners must now apply directly to OFCOM for radio licence issue and renewals. The certification process of the CAA still approves the radio equipment fitted to the aircraft.

Question 83

Operation of Installation The radio installation shall not be operated, whether the aircraft is in flight or not, except in accordance with the conditions of the licence issued under the laws of the country in which the aircraft is registered and only by a person duly licenced or otherwise permitted to operate the station under law.

Question 84

Change of Ownership A change of aircraft ownership invalidates the radio installation licence. The new owner must apply for a new licence.

Question 85

Radio Installation license Validity of Licence Licence is valid for 36 months and renewal can be applied for 2-months in advance of expiry.

Question 86

when ownership of an aircraft is transferred, if the aircraft remains on the same register, the noise certificate shall be transferred together with the aircraft

Question 87

who may issue a permit to fly

Answer 87

uk CAA or part 21 organisation that has approval