Recommendation Date
Recipient Name
Initiate with the aircraft manufacturers an investigation into the practicality of enhancing the survivability of the aerials of any ELTs in passenger transport aircraft which are hard wired into aircraft.
Reply Text
In New Zealand Civil Airworthiness Requirements Leaflet C.4, the CAA mandates standards for the installation of ELTs. Four items in this standard which are particularly relevant to the Commission's recommendation require the ELT installation to be such that:
• 'the location of the transmitter and antenna will minimise the potential for damage in accidents by impact or fire;'
• 'the transmitter and external antenna (if used) are mounted as close to each other as possible;'
• 'the attachment of the transmitter and external antenna (if used) to the airframe can support a 100g load applied through their respective centres of gravity in the plus and minus directions of the three principal axes of the aircraft;'
• 'the coaxial cable between transmitter and antenna has vibration-proof RF connectors on each end and when installed is secured to aircraft structures leaving some slack at each end;'

The intention is to minimise the probability of damage to the transmitter and antenna and their becoming separated in a crash. Nevertheless, the CAA will refer the Commission's recommendation to the relevant manufacturers of airline aircraft with a view to further enhancing the survivability of ELT antennas.
Related Investigation(s)