CS ACNS.D.ADSB.030 ADS-B Transmit Unit Approval
ED Decision 2013/031/R
(See AMC1 ACNS.D.ADSB.030)
The ADS-B transmit unit is approved and it is integrated in the Mode S transponder.
AMC1 ACNS.D.ADSB.030 ADS-B Transmit unit installation
ED Decision 2013/031/R
To be approved, the ADS-B transmit unit should hold an EASA equipment authorisation in accordance with ETSO-C166b and ETSO-C112d, including any additional requirements as required to comply with the provision of the AMC’s to Subpart D section 4 (e.g. On-the-ground status determination and maximum NIC encoding). Where such additional requirements apply, it is expected that the ADS-B transmit unit manufacturer supplies compliance information through a Declaration of Design and Performance (DDP), or an equivalent document
The broadcast of Selected Altitude and Barometric Pressure Setting are optional for equipment meeting ETSO-C166b and equipment should implement this optional functionality if available and in a suitable format
If using earlier versions of ETSO-C112( ), it should to be demonstrated that all applicable requirements from EUROCAE ED-102A have been implemented. This can be achieved by a positive deviation of compliance to previous versions of EUROCAE ED-73 that have been documented in the Declaration of Design and Performance (DDP).
CS ACNS.D.ADSB.035 ICAO 24-bit Aircraft address
ED Decision 2013/031/R
The ICAO 24 bit aircraft address is implemented as specified in CS ACNS.D.ELS.055.
CS ACNS.D.ADSB.040 Antenna diversity
ED Decision 2013/031/R
(See AMC1 ACNS.D.ADSB.040)
The ADS-B transmit unit employs antenna diversity under the same conditions as specified in CS ACNS.D.ELS.065.
AMC1 ACNS.D.ADSB.040 Antenna Diversity
ED Decision 2013/031/R
The 1090 ES data protocol includes a bit to indicate, at any time, if only one or both antennas (if installed) are functional. The corresponding parameter for the Single Antenna bit is contained in register 6516 (message element bit ‘30’) and should be set to the appropriate value.
Note 1: For detailed guidance on the required antenna diversity as a function of aircraft maximum cruising true airspeed capability, refer to AMC1 ACNS.D.ELS.065.
Note 2: For further guidance on antenna installations, see CS ACNS.D.ELS.060, CS ACNS.D.ELS.065, AMC1 ACNS.D.ELS.060 and AMC1 ACNS.D.ELS.065.
CS ACNS.D.ADSB.045 Antenna installation
ED Decision 2013/031/R
The antenna is installed as specified in CS ACNS.D.ELS.060.
CS ACNS.D.ADSB.050 Transmit power
ED Decision 2013/031/R
The ADS-B transmit unit has a peak transmit power as specified in CS ACNS.D.ELS.010(c);(d).
CS ACNS.D.ADSB.055 Simultaneous operation of ADS-B transmit units
ED Decision 2013/031/R
(See AMC1 ACNS.D.ADSB.)
If more than one ADS-B transmit unit is installed, simultaneous operation of the transmit systems is prevented.
AMC1 ACNS.D.ADSB.055 Simultaneous operation of ADS-B transmit units
ED Decision 2013/031/R
Manual switching between transmitters is considered acceptable.
Note: The requirement applies to ADS-B transmit units broadcasting on the same data link. It does not preclude simultaneous operation of dual link installations.
CS ACNS.D.ADSB.060 On-the-ground status determination
ED Decision 2013/031/R
(See AMC1 ACNS.D.ADSB.060)
(a) The on-the-ground status is determined and validated by the ADS-B Out system.
(b) The on-the-ground status is not set by a manual action.
AMC1 ACNS.D.ADSB.060 On-the-ground status Determination
ED Decision 2013/031/R
For aircraft with retractable landing gear, the on-the-ground status determination is typically provided through a landing gear weight-on-wheels switch. For aircraft that have fixed-gear, the ADS-B Out system should be able to determine the air-ground status of the aircraft using other means.
Installations that provide a means to automatically determine on-the-ground status based on input from other aircraft sensors are acceptable if they are demonstrated to accurately detect the status. Otherwise, ground status validation algorithms should be implemented, using speed thresholds that match the typical aircraft’s rotation speed as closely as possible.
It is noted that for the validation of a directly determined on-the-ground status that is not validated outside the ADS-B transmit function, validation against the aircraft’s typical rotation speed (rather than a fixed value of 50 m/s (100 knots)) might not have been tested in accordance with ETSO-C166b. If that is the case, it is expected that the ADS-B transmit unit manufacturer supplies compliance information through a Declaration of Design and Performance (DDP), or an equivalent document.
Detailed guidance material is provided in Appendix I.