Events related to aircraft missing over oceanic areas have led to several new requirements, amongst which is the introduction of a long-range Underwater Locator Device (ULD).

The ULD low frequency (8.8kHz) technology is used to increase the range at which aircraft submerged wreckage can be located.

It will be mounted on the aircraft structure free of sound absorbent materials and not in wing sections or empennage. The installation is in accordance with ARINC specification 667, which describes the removal, installation and maintenance aspects of an ULD installation.

Note that the ULD is not to be confused with the Underwater Locator Beacons (ULB) as installed on the CVR and FDRs. The ULD is complementary to the ULB and is mounted to the aircraft structure.

ICAO states that by January 1st 2018 aircrafts flying long range over water with a MTOW>27.000 kg must be equipped with an ULD. Long range over water is determined by the exceedance of the distance from a suitable emergency landing spot. The distance corresponds to 120 min at cruise speed or 400NM whichever is the lesser.

EASA states that by January 1st 2019 Passenger aircraft flying long range over water with a MTOW>27.000 kg and cargo aircraft with MTOW > 45.500kg must be equipped with an ULD. Long range over water is determined by a distance >180 NM from shore.

CARS 121 MOS 11.64 states that aircraft with a MTOW>27.000 kg carrying a life raft should have an ULD by December 2, 2023.

Other authorities have accepted similar rules.

Contact Fokker Services for other aircaft types.

Global Navigation Satellite System (GNSS) refers to a constellation of satellites providing signals from space that transmit positioning and timing data to GNSS receivers. The receivers then use this data to determine position, altitude, time, and velocity. This performance can be improved by regional satellite-based augmentation systems (SBAS).

SBAS improves the accuracy and reliability of GPS information by correcting signal measurement errors and by providing information about the integrity of its signals.  SBAS is essential for applications where accuracy and integrity are critical. SBAS is a key enabler of Performance Based Navigation (PBN) usage for Automatic Dependent Surveillance-Broadcast (ADS-B) and Localizer Performance with Vertical Guidance (LPV).