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ETSO-2C66b

European Technical Standard Orders (CS-ETSO) · CS-ETSO · EAR revision 14 Aug 2026

IRImplementing rule

ETSO-2C66b

DISTANCE MEASURING EQUIPMENT (DME) OPERATING WITHIN THE RADIO FREQUENCY RANGE OF 960-1215 MEGAHERTZ

1 Applicability

This ETSO gives the requirements which distance measuring equipment that is manufactured on or after the date of this ETSO must meet in order to be identified with the applicable ETSO marking.

2 Procedures

- 2.1 General

Applicable procedures are detailed in CS-ETSO Subpart A.

- 2.2 Specific

None.

3 Technical Conditions

- 3.1 Basic

3.1.1 Minimum Performance Standard

Standards set forth in EUROCAE document ED-54 (1987).

In addition to Chapter 5 of EUROCAE document ED-54, all materials used except small parts (such as knobs, fasteners, seals, grommets and small electrical parts) that would not contribute significantly to the propagation of a fire, must be selfextinguishing when tested in accordance with applicable requirements of CS 25 Appendix F.

3.1.2 Environmental Standard

See CS-ETSO Subpart A paragraph 2.1

Addition: equipment manufactured in accordance with this ETSO shall be compatible with 50 kHz VOR equipment.

3.1.3 Computer Software

See CS-ETSO Subpart A paragraph 2.2

- 3.2 Specific

None

4 Marking

- 4.1 General

Marking is detailed in CS-ETSO Subpart A paragraph 1.2.

- 4.2 Specific

None.

- 5 Availability of Referenced Document

See CS-ETSO Subpart A paragraph 3.

IR · ETSO-2C66b — CS-ETSO · ED Decision 2003/010/RM · CS-ETSO Easy Access Rules · EAR revision 14 Aug 2026

All rules in SUBPART B -LIST OF ETSOS

Consolidated from the EASA Easy Access Rules (revision 14 Aug 2026, extracted 17 Aug 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.

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