HGFA Skysailor Magazine

26 SKY SAILOR May | June 2018 Wing Tips: Sending Out An SOS R ecently, I had a discussion with a pilot who had had the misfortune of being involved in an accident during a competition. It was an inflight incident that resulted in him landing in a tree and sustaining a leg injury. Fortunately, he was carrying a Personal Locator Beacon (PLB) which he activated accordingly. In the post-accident analysis, one interesting point came out regarding the expectations a pilot might have after the SOS button is pressed on a PLB. Specifically, how long one has to wait for rescue once one of these devices is activated and whether the emergency response is the same over different brands of PLBs and trackers. Both the pilot and I did a bit of research and looked at what we considered the most popular PLB/tracker devices pilots are using. The list included: ➲➲ Spot messenger ➲➲ Delorme Inreach ➲➲ Australian Personal Locator Beacon (e.g: ACR ResQLink + PLB) ➲➲ 3G Tracker (e.g: Flymaster Tracker) All these PLBs use different technologies, so the question is: Does one PLB/tracker provide better performance and/or response than others? Spot Messenger & Delorme Inreach Both, the Spot Messenger and Delorme Inreach devices provide tracking and limited satellite communication. Depending on the model selected, the pilot can send pre-programmed messages from the device through the satellite system. Also, both devices have an ‘SOS’-type button if the pilot requires rescue. The main difference between the two brands is the satellite system used. The Spot product family uses the GPS satellite network to determine a customer’s location and the GlobalStar network of satellites to transmit messages and GPS coordinates to others. The DeLorme product family use the GPS satellite network for position information and the Iridium satellite network for messaging. The Iridium satellite system is said to provide more coverage due to a greater number of satellites, however, it costs more than GlobalStar. Despite using different satellite systems, when you press a button on a Spot Messenger or Delorme unit, the SOS message is relayed to a 24-hour emergency response centre in the USA (GEOS: International Emergency Response Coordination Center aka IERCC). In the first instance, the emergency response centre attempts to phone the device’s owner, then the two ‘next of kin’ contacts listed in the device’s registration information. The reason being that 80 to 90% of activations are false alarms. Once the activation is determined to be valid, the information is then relayed to the AMSA’s (Australian Maritime Safety Authority) 24-hour response centre. AMSA “…maintain a national search and rescue service for the maritime and aviation sectors.” The AMSA emergency centre reviews the information received from GEOS and may confirm activation validity by phoning the contacts on the registration list again. They will then contact the appropriate police services in the area of activation and hand over rescue coordination to them. Personal Locator Beacons Personal locator beacons (like the ACR ResQLink+), don’t provide any messaging functions. Instead, when activated, they provide a SOS signal to the Copsas-Sarsat satellite system on the 406MHz frequency band. AMSA has access to three ground station receivers that receive information from the Copsas-Sarsat satellite system. The PLB activation information is passed directly to the AMSA 24-hour emergency response centre. The response centre then endeavours to contact the owner, followed by the ‘next of kin’ listed in the PLB’s registration information, to determine if the activation is valid. Once validated, they pass the information to the local police for the emer-gency response. I spoke to a liaison officer at AMSA about the differences between Spot, Delorme and PLBs and she advised that all three systems get coordinated through the AMSA 24-hour response centre. However, PLB’s activation information is sent directly to AMSA (they have satellite receivers in Albany, Bundaberg and Wellington), and they do the work of contacting the owner and the ‘next of kin’ on the device’s registration details. She pointed out that PLBs are the cheapest of the three systems to buy and have no ongoing costs. She described that event organisers of, for example, sailing competitions ask their competitors to insert the competition organiser’s details in the second next of kin entry to enable the emergency response centre to contact the organiser quickly. This may be useful in PG/HG competitions. She also explained that many people think that pressing the SOS button on these devices will initiate an immediate response from rescue authorities. This is not the case, as there is typically a 50-minute delay between SOS activation and local authorities being informed and mobilised. 3G Trackers The SOS function in the Flymaster 3G trackers doesn’t contact GEOS or AMSA – it merely sends pre-defined emails that have been set up in the tracker's registration page. Naturally, 3G phone reception is required for this function to work. SOS Reception Reliability Depending on location, terrain and amount of tree cover, the reception of SOS activation is variable: ➲➲ 3G is limited to 3G mobile reception areas and the signal may punch through tree cover. Why it’s important to be mindful of response expectations when activating a Personal Locator Beacon. by Peter Allen