Gliding is a sport that has always been at the bleeding edge of technology, from the Wright brothers to today's gliders with 30 metre wingspans that achieve glide ratios of 60:1*. Gliders are being used in grand prix racing, and some even come with jet engines. Flights of 1000km are regularly being recorded – without fuel. There have even been flights of 3000 km achieved recently. Gliders have been recorded flying at heights of 42,000 feet – this is not for the faint hearted!
This is a highly competitive, high tech sport as well as a gentle, relaxing past time. Instrumentation, aeronautical design, biosciences all play a part in pushing the boundaries of flight through gliding.
*60:1 means that a glider at 1km up can glide for 60km.
FLARM is quite simply a FLight AlaRM and was developed by some very bright electrical engineering glider pilots to in Europe to warn each other of the risk of mid air collisions flying around the European Alps where gliders previously could literally fly around a blind corner of a mountain one way and risk running into a glider flying around the same blind corner flying the other way.
The technology has been developed into Australian conditions by local electrical engineer/glider pilot locally and re-badged as the “Aus FLARM” and works equally as well in our generally more open skies. Essentially what it does is warn each user/pilot of the risk of collision from another user, particularly when you might not be able to physically see them due to either terrain (mountains), cloud or more likely just that they are sneaking up behind or above you.
The technology behind the FLARM is quite advanced and uses smart box (about the size of a iPhone) that has a precise GPS in it (much more precise than your average smartphone or Tom Tom) and on one channel of its brain, computes where its glider has been, where it is now, and thus how fast it is going (in three dimensions) and estimates where it is going in the next few second based on current 3 dimensional trajectory. It then sends this information out to all the other matching FLARM boxes in the listening area. The other side of brain is a receiver and a calculator, such that it receives matching signals from all the other FLARMS and it can not only show instantly where all the other users (gliders) are (even those that can’t be seen by eye), but also then calculates into the future where they will be and where you will be and tries to predict possible collisions and provides an alarm warning.
Considering this is working in three dimensions and noting that gaggles of gliders often choose to thermal/fly in reasonably close proximity at speeds ranging from 80 – 250km/h, there has been a lot of fine tuning of the software to make the alarms real and not erroneous. With excellent user feedback of avoiding near misses, the device has recently become mandatory in most competitions and Like all good bits of technology, smart users have sought to adapt it and use it to a competitive advantage as it can be used to show where some of your competitors are which at times can be used to advantage.
However the primary means of collision avoidance remains maintaining a good lookout.