Maintenance Directive NL-2011-002R2

1. The design holders’ instructions for continuing airworthiness prevail over this MD. In absence of any specific recommendations of the design holder the instructions of this MD apply.
2. The aircraft maintenance program must establish compliance with the instructions specified in Table 1 below . Table 2 provides the associated instructions.
3. One-time variation of the intervals is allowed. Refer to Informatieblad Permitted Variations for instructions.
4. Standard aviation regulations apply to the performance of the periodic functional checks, certification authorisation and maintenance records and retention periods, except that for MLA’s and amateur built aircraft (under Dutch rule) these periodic functional check tasks have to be performed by appropriately certified organisations or authorised persons instead of the pilot/owner.
5. Where the periodic functional check requirements relate to specific components that are not attached to the aircraft, e.g. in balloons, the certificate of release to service should include reference to the part number and serial number of these components.
6. The periodic functional check requirements as specified in Table 1 apply to the mandatory equipment only.

Table: 1

System	Maximum interval	Applicability	Instruction (Table 2)
Pitot-static, including instruments	24 months	Aircraft with non-MSG-3 AMP’s 1)	1
Radio navigation	24 months	Aircraft with non-MSG-3 AMP’s 1)	2
Radio identification	24 months	Aircraft with non-MSG-3 AMP’s 1)	3
Magnetic compasses and magnetic compass systems	24 months	Aircraft with non-MSG-3 AMP’s 1)	4
Aircraft Mass and Balance	48 months	Aircraft with an ICAO or Special CofA, excluding balloons. 2)	5

¹⁾ Note that this MD also applies to aircraft with an MSG-3 AMP where the design holder refers to national regulations for periodic functional check requirements of these systems.

²⁾ For Commercial Air Transport the Air Operations Regulations contain requirements for periodic weighing.

Table 2:

Ref.	Instructions
1	Functional check and leak check of a) Barometric altimeter system. In accordance with the design holder’s instructions, or, in absence thereof, in accordance with FAR Part 43 Appendix E to Part 43, paragraph (b)(1). b) Speed indication systems, including vertical speed indication systems. In accordance with the design holder’s instructions, or, in absence thereof, in accordance with the calibration instructions provided by the component manufacturer. In absence of design holder’s instructions for the leak check, AC43.13-1B chapter 12- 58, resp. 12-59 may be used.
2	Functional check in accordance with the design holder’s specifications and instructions.
3	Operational check in accordance with the design holder’s specifications and instructions.
4	Functional check that the accuracy complies with the design holder’s specifications and adjust as necessary. Record the compass inaccuracies that remain after adjustment on a compass deviation card as required by the applicable C ertification Specification (e.g, CS 23.1547, CS-22.1547). The deviation card should be placed at the compass location. If the use of specific systems has a significant effect on compass readings, then this should be accounted for. In absence of design holder’s specifications, AC43.13-1B chapter 12-37 may be used. The check requires a designated area on the airport. Contact the airport for information about these areas.
5	Aircraft weighing to be performed to determine operational empty mass and centre of gravity, per TC-holder’s instructions. In absence thereof, AC43.13-1B chapter 10 may be used.

1. GM - Explanation of AMC and GM

a) Acceptable Means of Compliance (AMC). By complying with the AMC the corresponding requirement is considered complied with. Deviations may be accepted by CAA-NL, provided that the applicant demonstrates that an equivalent level of safety is obtained.

b) Guidance Material (GM) Information contained in Guidance Material is non-mandatory.

2. GM – Non-mandatory systems

This MD only mandates certain checks on certain mandatory equipment. It should be noted that all operational and emergency equipment fitted is correctly installed and serviceable or clearly identified as unserviceable.

3. AMC – Functional check on-wing or off-wing

The checks required by this MD are intended to be performed on-aircraft (‘on-wing’), to ensure that the complete system functions within specification. If however, one chooses to perform functional checks on specific equipment off-aircraft (‘off-wing’), possible inaccuracies of the remainder of the system need to be considered, as well as possible negative effects of the removal and installation. For pitot-static systems, the latter means that at least a leak check should be performed after re installation.

4. AMC – Instructions for transponder functional check

Operational checking of the transponder is required, as part of the radio identification equipment check. Maintenance tests should include a periodic verification check of aircraft derived data including the ICAO 24 bit aircraft address using suitable ramp test equipment¹. For this transponder operational check, please follow the instructions in EASA SIB 2011-15, Appendix 1, which are provided to minimise the hinder such testing causes to air traffic control, with the following amendments for tests in FIR Amsterdam:

a. Instead of contacting the local air traffic control unit as indicated in paragraph b of this appendix, the ATC The Netherlands Operational Helpdesk should be contacted:

• Tel: + 31 (0)20 406 2201; 0700 – 1830 LT on weekdays; 0700 – 1700 LT during weekends
• Fax: + 31 (0)20 406 3672
• Email: ops_helpdesk@lvnl.nl

b. Instead of changing the Aircraft Identification (Flight ID) to the first 8 characters of the name of the company conducting the tests, as indicated in paragraph d of this appendix, the Flight ID should not be changed, to prevent the risk of error in resetting it.

¹ Ref JAA Leaflet 13 Revision 1, ‘C ertification of Mode S Transponder Systems for Elementary Surveillance’ and EASA AMC 20-13: ‘C ertification of Mode S Transponder Systems for Enhanced Surveillance (EHS)’.

5. AMC – Instructions for Electronic Locator Transmitter (ELT) operational check

For test instructions, see http://www.cospas-sarsat.org. Although many ELTs in the 406 to 406.1 MHz band have self test functions that emit a recognisable test pulse that would not result in Search and Rescue teams being deployed, these transmissions do require satellite processing time. Therefore, live unshielded testing of ELT’s should not take place, to prevent COSPAS-SARSAT system problems to process distress calls. For performing functional tests, the following options exist:

a) For ELTs that can be removed from the aircraft (e.g. Survival ELTs and Automatic Portable ELTs) the operator can remove the ELT from the aircraft and test it in either a shielded room or a shielded bag. Shielded ELT test bags can be obtained from most ELT manufacturers.

b) For ELTs that cannot be removed from the aircraft (or those which the operator wishes to test in situ) an antenna cap should be used to prevent the ELT transmission from going beyond the aircraft. Antenna caps can be obtained from either an antenna manufacturer or, in some cases, from the ELT manufacturer. Operators may also use self-manufactured antenna caps provided that they can be shown to prevent transmission from the aircraft.

c) Some ELTs have test functions that do not actively transmit on the emergency frequencies or which send codes that are not recognised by the COSPAS-SARSAT satellites. In these cases live testing can be performed as long as the operator can demonstrate that it will not cause an interaction with any of the SAR services. In all cases, procedures for testing ELTs should be based on the manufacturer’s recommended testing practices and, where applicable, should be performed using their recommended test equipment unless this would result in unshielded testing.

6. AMC – Instructions for magnetic compass compensation

a) In case the use of specific aircraft systems causes large compass deviations and flights are foreseeable with the systems ON and with the systems OFF, then separate compass deviation tables should be produced with the systems ON and with the systems OFF.

b) More detailed guidance information is provided in CAA-UK CAP 562 Civil Aircraft Airworthiness Information and Procedures, Book 2 , Leaflet 34-20.

c) Designated compass compensation areas should be treated by maintenance providers in the same way as special equipment requiring calibration for the performance of maintenance. This means that the maintenance provider should verify that standards are met. CAA-UK CAP 562 Civil Aircraft Airworthiness Information and Procedures, Book 2, Leaflet 34-10, provides useful guidance.

d) Besides the periodic functional check requirement, compass accuracy should also be verified in any of the conditions listed in AC43-13 chapter 12-37 under (a):

• (a) When the accuracy of the compass is suspected.
• (b) After any cockpit modification or major replacement involving ferrous metal.
• (c) Whenever a compass has been subjected to a shock; for example, after a hard landing or turbulence.
• (d) After aircraft has passed through a severe electrical storm.
• (e) After lighting strike.
• (f) Whenever a change is made to the electrical system.
• (g) Whenever a change of cargo is likely to affect the compass.
• (h) When an aircraft operation is changed to a different geographic location with a major change in magnetic deviation.
• (i) After aircraft has been parked on one heading for over a year.
• (j) When flux valves are replaced.

7. AMC – Appropriately approved persons and organisations

Note that in all cases, certifying staff should have the appropriate aircraft or group rating endorsed on the license/authorization and should ensure having at one’s disposal all tools, equipment and documentation necessary and be able to demonstrate being competent to perform the tasks.

Minimum authorisation requirements:

a) For aircraft with an EASA Certificate of Airworthiness or EASA Permit to Fly:

Maintenance tasks shall be signed off/certified by appropriately trained certifying staff within the scope of their EASA Part-66 AML in accordance with the requirements of Part-66, in particular 66.A.20 and accompanying AMC & GM, and where applicable within the scope of the internal company authorization and procedures.

b) For aircraft referred to in Annex I of the Basic Regulation:

Amateur built aircraft

Amateur built aircraft fall under Annex II of the Basic Regulation (EU) 2018/1139. An amateur builder is the person who built the aircraft, but is not necessarily the designer of the aircraft type. An amateur builder may install the systems and instruments, but the maintenance specified in this MD should be performed by appropriately certified persons or organisations. These persons and organisations are not required to have the particular amateur built aircraft on their approved scope, as long as they are endorsed with a license or organisation approval to perform these tasks on technically similar aircraft.

Microlight aircraft (MLA)

MLA are defined in the “Regeling MLA’s” and fall under Annex II of the Basic Regulation (EU) 2018/1139. In general, there are no qualification requirements for anyone performing MLA maintenance, except that the maintenance specified in this MD should be performed by appropriately certified persons or organisations. These persons and organisations are not required to have the MLA on the scope, as long as they are endorsed with a license or organisation approval to perform these tasks on technically similar aircraft.

Design Approval Holder: The holder of a type-certificate, restricted type-certificate, supplemental type-certificate, European Technical Standard Order (ETSO) authorisation, major repair design approval or any other relevant approval deemed to have been issued under EC 748/2012, Part-21.

EASA CofA: EASA-standaard-BvL or EASA-beperkt-BvL as per Besluit luchtvaartuigen 2008 Chapter 4 article 7.

Functional check: A quantitative check to determine if one or more functions of an item performs within specified limits.²

ICAO CofA: ICAO-standaard-BvL as per Besluit luchtvaartuigen 2008 Chapter 4 article 7. Does not include CofA’s issued for aircraft under the Basic Regulation 216/2008 as such aircraft hold an EASA CofA.

Magnetic compass: also referred as ‘magnetic direction indicator’ in certification specifications.

Mandatory equipment: The minimum operational and emergency equipment required for the intended flight as defined in the applicable operational regulations. (E.g., Regeling navigatie- en telecommunicatie-installaties, the applicable subpart of Commission Regulation for Air Operations detailing the Instruments, Data and Equipment).

Operational check: An operational check is a task to determine that an item is fulfilling its intended purpose. Does not require quantitative tolerances. This is a failure finding task.

Special CofA: speciaal-BvL as per Besluit luchtvaartuigen 2008 Chapter 4 article 7.

RPAS: Remotely Piloted Aircraft Systems (also known as UAS or Unmanned Aerial Systems).

² ATA MSG-3 Revision 2005.1.