Last night I had the pleasure of talking with a local Scout group about search and rescue in Australia. It was very refreshing to speak face to face with our future leaders, and explain to them some of the challenges facing those who search for, and rescue those who get lost of require assistance in our vast country.
I was impressed at the questions asked by the Scouts, and their intuitive thinking. For example I explained that a search and rescue aircraft may deploy a life raft to people who require assistance in the middle of the desert. When I asked what the benefit a life raft might be to these people, the Scouts correctly identified that the raft can provide shelter, and is often equipped with a simple first aid kit and some drinking water. It was a very pleasing to hear this coming from a bunch of kids whom we normally associate with computer games, not the great outdoors.
One activity we did was to try to make letters from the Ground to Air Emergency Code. We simply tried to make a V (Require Assistance) and an X (Require Medical Assistance). The challenge was to make these letters large enough to be easily observable from an aircraft searching for them.
So how big do they need to be? The basic physics of the search aircraft operation was easy to explain. Search aircraft typically operate between 500 and 1000 feet above ground level, and travel at 120 knots. For our metric generation, this means they operate at around 150 to 300 metres above sea level, and travel around 200 kilometres per hour. The letters therefore need to be large – and in an open space – and in most cases are simply made with material to hand.
So why do we need to know the Ground to Air Emergency Code? If the search authorities are alerted via a PLB or EPIRB, there is no additional means of communications to allow you to advise the nature of your distress. The search authorities will attempt to request an aircraft of opportunity operating nearby to over fly the distress location, whilst specialised search and rescue units respond. This means that the first aircraft on scene may not be able to rescue you, or even communicate with you. Therefore if you’re able to alert the SAR authorities that you require medical assistance (X), the SAR authorities will be better prepared to deal with your situation when they arrive on scene.
The Ground to Air Emergency Code, and other communication means is explained further in “Save Our Selves, A guide to getting help in remote areas“