406MHz ELT’s and 406MHz Antenna’s Presented by Lloyd Klee Aviation Safety Supplies Ltd. NZHA Conference June 2016

Reasons as ELT to “failures” Most Helicopter ELT failure to alert RCC are due to Broken antenna (as it is on the outside of the aircraft) Separation of BNC connectors on Coax Cable Failure of the coax cable by earthing Failure of the ELT to stay in the mounting bracket (Velcro strap separates or is loose) Incorrectly mounted to allow G switch to activate (many Artex ME406 mounted in AF configuration) ELT not correctly encoded (factory maintenance code) Fire NZHA Conference June 2016

Slow Roll overs Helicopter accidents in particular have a high failure of ELT systems generally due to broken antennas Loss of control -slow roll overs will not activate an ELT even with multi axis G –Switches as the G-Switches are all the same specification and slow rollover sideway forces are always less than forward or vertical accident forces NZHA Conference June 2016

Antenna Location One of the major issues is the location of the Antenna Many are installed on the side of the helicopter – Which side? The side that the helicopter naturally lies on due the torsional rotation of the blades NZHA Conference June 2016

Antenna Location The rest are on the top and just as vulnerable NZHA Conference June 2016

Results of ELT location Then there is the issue with the location of the ELT ! The main mast to the rotor can crush the ELT especially if it is a R22 or R44 NZHA Conference June 2016

Antenna Cables through bulkheads The new cable “stripper” Passing Coax thru a bulk head is a nonsense The Coax in this case earthed and no signal was receipted NZHA Conference June 2016

Velcro straps that are not tight or suffer UV deterioration Strap must be tight, I recommend replacement at battery time Once again, no signal heard due to broken antenna NZHA Conference June 2016

So what is to be done to improve installations ? NZHA Conference June 2016

We have Tested an antenna within a Tail Boom – R44 NZHA Conference June 2016

Test of an antenna within a tail boom Check BT100 2015- 043 Power measured BT100 = 35.2dBm Power receipted on GEO satellite = -134.55 dBm average This test was with the ELT out in the open NZHA Conference June 2016

Within Tail boom Test- (success)  406AP- Vertical Antenna bent in “h” shaped to fit boom then tail boom enclosed Power measured on LEO satellite -138.23dBm average Satellite location correct Latitude 37.74823 longitude 176.07684 This test was also successfully repeated with a whip antenna Horizontal within the tail boom NZHA Conference June 2016

Testing on three separate occasions we have has proven That a 406MHz antenna within an aircraft fuselage will transmit successfully to the Cospas-sarsat system The tests show that it matters little if the fuselage material is composite or aluminium i.e. You do not need a window However NOTE that the signal will not transmit through a carbon fibre fuselage NZHA Conference June 2016

The Issues We needed to change some of the wording of the RTCA document D-204A This is to do with antenna location The word shall be needed to be replaced with should be Current Wording DO-204A 3.1.10.1 Antenna Polarization The antenna shall be mounted to provide either right-hand circular or vertical polarization when the aircraft is in the normal flight attitude. Actually most, if not all 406MHz ELT antennas are now omni directional NZHA Conference June 2016

The Issues 3.1.10.4 Internal Antenna Location The antenna shall / should be installed as close to the ELT unit as practicable, insulated from metal window casings and restrained from movement within the cabin area. The antenna shall / should be located such that its vertical extension is exposed to a RF transparent window. The proximity to the vertical sides of the window and to the window pane and casing and the minimum acceptable window dimensions shall / should be in accordance with the equipment manufacturer’s instructions This part of the regulation written around 121.5/243MHz ELTs NZHA Conference June 2016

Results if wording change Engineers will be able to install 406MHz ELT systems in the most crash worthy position & still comply with international regulations ELT systems currently fail due to these same regulations that prevent ELT antennas being placed in a crashworthy position NZHA Conference June 2016

Failure- Back to square one Regretfully, and despite the evidence of the testing, I have failed to get the RTCA working group to change the wording. The people within the group want surety of their documents. (NASA & others do not like the word should) At this stage, it appears that the working group do not trust installers to use their judgement They want rules that are black & white and not open to interpretation NZHA Conference June 2016

CAA requested support Following a request from me, the Director wrote to the chair of the WG and requested support for the research that I undertook The group responded that they (including NASA) could not afford to re conduct the tests 1 (really?) NZHA Conference June 2016

However in the meantime, PLEASE Change the location of antenna to a crash worthy position Check the Coax cable does not pass over fuselage joints or through metal bulkheads Always ensure that there is some slack in the coax cable Ensure all ELT installations are engineered and not installed as per the “book” because the NZ accident data clearly show that the “book” is wrong NZHA Conference June 2016

However in the meantime As of 10 June 2016, The NZ CAA have amended AC43-14 see https://www.caa.govt.nz/Advisory_Circulars/AC043_14.pdf AC43-14 quote “Where an antenna is not installed in an approved location, suitable testing should be carried out to determine the suitability of the selected location.”  AC43-14 also uses the word SHOULD BE for Location  Polarisation  but still requires an electronic window for an internal antenna  Thank you NZ CAA NZHA Conference June 2016

Next generation Cospas-Sarsat 406MHz beacon systems to include Mandatory GNSS specifications (GPS) In-flight activation because of flight anomaly including Altitude, banking, depressurisation ELT Power source options (rechargeable battery) Increase ELT Crashworthy specifications Return link services specifications options (SMS)? Second generation homing? Possibly just 406MHz (although I am against that) Improved Antenna and cabling specs incl. mandatory fire proof sleeves Effectively a flight computer connected to the ELT providing inflight data for the ELT to act from NZHA Conference June 2016

Next generation Cospas-Sarsat 406MHz beacon systems RTCA are developing aviation-based 406 MHz MEOSAR distress alerting and location proposals for consideration by Cospas-sarsat. Defining the frequency of transmission of data and applicable parameters- Rapid 406MHz pulses in the first few minutes Can the MEOSAR cope with flight 1000Km/hr Most importantly reduce the time for the first 406MHz burst to 5 seconds? (currently 50 seconds) & making GPS mandatory NZHA Conference June 2016

The new MEOSAR system Russia (SAR/GLONASS), USA (SAR/GPS) and ESA/EC (SAR/Galileo) working to include 406 MHz repeater instruments on future medium Earth altitude orbiting (MEO) GNSS satellite constellations •Constellations will be fully compatible (72 Satellites) • Global detection + location: • Any beacon without embedded GPS - greater than Cospas-Sarsat accuracy with 3 bursts or less • Self-locating beacons - GPS accuracy after single beacon burst •Return Link Capability – May allow two messages •Currently under in NZ NZHA Conference June 2016

Existing C-S system vs MEOSAR NZHA Conference June 2016

One Solution to ELT issues As a commercial plug with a small apology  You can OVERCOME many of the existing issues by Installing a Kannad Integra which has a backup 406MHz antenna inside the actual ELT thereby overcoming two of the main failures The Coax Cable and connectors & The Antenna breaking & GPS NZHA Conference June 2016

Also announced-10 year warranty NZHA Conference June 2016

Summary The NZ CAA has supported my involvement within the RTCA working group. However the RTCA is, at this stage, not going to assist with a wording change As I indicated previously, they want specifics not a generalisation. ( Shall vs Should) HOWEVER with the new revision of AC43-14 the Director of NZCAA has given the installers an opportunity to save more lives with better ELT installations – We all know about that golden hour NZHA Conference June 2016

The Tui beer circle of life- yeh right NZHA Conference June 2016

Questions ?? For any questions or comments on this presentation, email LKlee@aviationsafety.co.nz NZHA Conference June 2016