Secondary Antenna Switching Device SASD Patent 547107 Presented

Secondary Antenna Switching Device ( SASD )- Patent 547107 Presented by Lloyd Klee 10/7/2020 © www. aviationsafety. co. nz 1

Project Goals • The project goal is to improve the ability of locating a crashed aircraft in the event that the 406 MHz ELT primary external antenna is compromised. 10/7/2020 www. aviationsafety. co. nz 2

Background • A recent helicopter crash, ZK-HTF late 2005 in New Zealand, highlighted the fragility of ELT antennas. • The 406 MHz ELT in this high speed incident functioned as designed • With the external antenna ripped off by a tree upon impact, the 406 and 121. 5 MHz transmissions were too weak to be picked up by the Cospas-sarsat system or searching aircraft. 10/7/2020 www. aviationsafety. co. nz 3

Background • The helicopter was found some 15 days after going missing. • It was located in a small bush covered creek bed 15 metres (50 feet) wide. • The area had been flown over a number of times by searching aircraft and the land owner had walked by the crash scene without realising that the helicopter was within a few metres of his path. 10/7/2020 www. aviationsafety. co. nz 4

ZK-HTF • ZK-HTF Eurocopter 120 B 10/7/2020 www. aviationsafety. co. nz 5

Here is ZK-HTF ! 10/7/2020 www. aviationsafety. co. nz 6

Actual site of crash 10/7/2020 www. aviationsafety. co. nz 7

Close up of crash site 10/7/2020 www. aviationsafety. co. nz 8

After bush had been cleared 10/7/2020 www. aviationsafety. co. nz 9

ZK-HTF • Internal position of Kannad 406 AF, post crash 10/7/2020 www. aviationsafety. co. nz 10

ZK-HTF • Remains of the external antenna, the branch is above 10/7/2020 www. aviationsafety. co. nz 11

Antenna remains 10/7/2020 www. aviationsafety. co. nz 12

Antenna Test Results d. Bu. V/m • Antenna Vertical Horizontal • Damaged 121. 5 MHz • Auxiliary Antenna 24. 5 111. 4 22. 7 92. 3 • Damaged 406 MHz • Auxiliary Antenna 82. 5 131. 7 72. 6 105. 1 10/7/2020 www. aviationsafety. co. nz 13

ELT • 10/7/2020 www. aviationsafety. co. nz 14

Summary • The tragedy was that the 406 AF-H ELT activated upon impact but the transmissions were not detected as the external antenna was destroyed. • In this case, had the antenna been on the other side of the aircraft, it is possible that the antenna would have survived the impact. For a report on the actions of the rescue coordination centre go to http: //www. nzsar. org. nz/reports. html 10/7/2020 www. aviationsafety. co. nz 15

Other reasons for failures to detect an ELT An ELT could “fail” for other reasons such as: • An electronic malfunction of the ELT or remote control • Antenna cables breaking on impact • The ELT being inadvertently turned off on the remote control • Lack of or poor service to the ELT 10/7/2020 www. aviationsafety. co. nz 16

Solution ? • Directly as a result of this incident, a development of a Secondary Antenna Switching Device (SASD) has been achieved • This will allow for an auxiliary antenna to be fitted to the SASD or at a nearby location within the fuselage which will be activated if the external antenna is damaged. 10/7/2020 www. aviationsafety. co. nz 17

Solution • The direct cost of searching for ZK-HTF was US$1, 400, 000 • Had the SASD device been fitted and worked as designed, the search cost would have been less than US$3000 10/7/2020 © www. aviationsafety. co. nz 18

Solution ? • The SASD is located between the fixed ELT and the primary external antenna. • In the normal state, the SASD has no effect on the circuit. It is “transparent” or INERT. • However, should the external antenna be damaged in a crash, the SASD will detect this fact via the activation of the 406 MHz ELT 10/7/2020 www. aviationsafety. co. nz 19

Solution • The SASD will use the first 406 MHz signal from the ELT to detect the fact that the primary external antenna has been damaged. • The 160 msec carrier lead signal is utilized and the SASD will switch rapidly to the auxiliary antenna within 5 msec. 10/7/2020 www. aviationsafety. co. nz 20

Solution l. If damaged, all further 406 MHz and 121. 5 MHz transmissions will be passed to the auxiliary antenna. The switched relay will stay in the alternate auxillary antenna position as the SASD has its’ own inherent battery power l 10/7/2020 www. aviationsafety. co. nz 21

SASD 10/7/2020 © www. aviationsafety. co. nz 22

SASD setup option • ELT to SASD with auxiliary antenna 10/7/2020 © www. aviationsafety. co. nz 23

Summary • In the passive (non operational ) state, SASD always remains connected to the primary antenna • If the secondary antenna is activated, the primary antenna can be restored by pressing the reset switch on the SASD 10/7/2020 www. aviationsafety. co. nz 24

SASD Block Diagram • 10/7/2020 © www. aviationsafety. co. nz 25

Solution • When activated the SASD will result in a power loss of only 0. 5 d. B • This is well within the specifications as laid down by Cospas-sarsat of 5 watts plus or minus 2 d. B as per C/S S. 007 page 6 - 49 clause 5. 3. 1. 3 10/7/2020 www. aviationsafety. co. nz 26

Patent 547107 approved • A worldwide patent has been applied for NZ # 547107 • A new TSO currently being written 10/7/2020 www. aviationsafety. co. nz 27

Sales l It is anticipated that the SASD will be sold as a standard accessory for a 406 MHz antenna or ELT l 10/7/2020 Sales of the SASD, once all necessary approvals are in place, will be sold via ELT & antenna manufacturers www. aviationsafety. co. nz 28

Current Status • Overview of progress against schedule – On track initial concept, patent, testing & samples produced – On schedule with testing and approval process – Testing has been accomplished with auxiliary antennas transmitting from within various fuselage types 10/7/2020 www. aviationsafety. co. nz 29

Auxiliary Antenna Trials 10/7/2020 www. aviationsafety. co. nz 30

Tail Boom • Inside Tail Rotor boom, structure is Aluminium and Nomex • The antenna is visible behind battery box 10/7/2020 www. aviationsafety. co. nz 31

ELT Growth 10/7/2020 www. aviationsafety. co. nz 32

Logo • Our logo includes a view of the Earth as seen by Apollo 17 in December 1972. Upon leaving the lunar surface, Commander Gene Cernan said • "we leave as we came, and, God willing, we shall return, with peace and hope for all mankind. " • 10/7/2020 © courtesy of NASA www. aviationsafety. co. nz 33

Contact Details • • 10/7/2020 Aviation Safety Supplies Ltd Phone +649. 4206079 Fax. +649. 4209279 Email sales@aviationsafety. co. nz www. aviationsafety. co. nz 34