THINGS YOU NEED TO KNOW…
Should I blow?
The key to successful deployment is early detection and recognition that it’s an accident, not just some heavy braking or a controllable rear wheel slide. When the D-Air Street was launched in 2011, it was a two-part system with a sensor kit (the M-kit) and the vest (J-kit). The M-kit has an under seat sensor to detect impacts from the rear, fork sensors to detect front impacts and a bar-mounted computer processor unit (CPU) that also displays status. The underseat sensor also detects if the motorcycle is falling. The M-kit is powered from the bike’s electrical system and the J-kit has a self-contained battery that is recharged by a phone-style charger. Dainese claim over 20 hours of riding time from one charge. The LCD display on the CPU informs the rider of the status of the vest’s battery, whether the two kits are connected properly and flags up any errors with the system. The J-kit and M-kit both have phone-style SIM cards and communicate wirelessly. If it detects an accident, the M-kit sends the signal to inflate the airbag and it takes 45 milliseconds from first contact between bike and a foreign object for the vest to be fully inflated. The disadvantage of this system is that if you sell the bike the M-kit needs to be removed and set-up on your new machine. The D-Air Race version and the Alpinestars Tech-Air Street have always had on-board processors and the D-Air Street is the same for 2017.
Road or Race?
The main difference between Road and Race with Alpinestars and Dainese is the deployment circumstances. As there are a lot of relatively low-speed get-offs by racers during practice, the D-Air Race only activates above 50kph and it has to be a highside and lowside with rolling, similarly with Alpinestars. Because road accidents are often collisions, and below 30mph the Street versions have a 10kph activation speed and can detect headon and lateral collisions with either stationary or moving objects, as well as highsides and finally lowsides with or without rolling. At 50 kph (31mph) the average time between a motorcycle making initial contact with, say, a car and the rider hitting that car is just 100 milliseconds. Alpinestars used a target of 70 milliseconds, Dainese triggers in 40 milliseconds.
Coverage
Another difference is the capacity of the airbags themselves. The D-Air Racing Misano is 4 litres and covers the shoulders, collarbone and back. The Mugello R is 9 litres - covering again the back, shoulders, collarbone and lower rib cage (false ribs). The Street Range is 11 litres and covers the chest as well. The road-going version of Tech-Air also takes in the shoulders, chest, full back and also the sides. Alpinestars also switched to a new one-piece woven material for 2015 in which the bag is created entirely in the loom, with no subsequent stitching or cutting. The result is a very fine, thin airbag.