I must be not understanding, overun. you suggest that EMAS' mechanism for energy dissipation is 'braking'. If a 125 meter bed 'effectively' provides 175m of 'additional runway braking', then the efficacy of its use is barely marginal.
The mechanism as I understand it has fibrous and frangible concrete installed as an 'arresting bed'; as the material decomposes with the passage of the landing gear, it provides greatly enhanced arrestment due friction and non uniform crumpling of the supporting material. My guess is that the landing gear is destroyed, the EMAS install is most definitely destroyed. But the sacrificial nature of the installation is a design consideration. Better to save lives than landing gear and lightweight frangible 'runway'?
Better than runway braking, surely?
I have to concur with Sqwak 7700, the EMAS system will attenuate velocity better than runway. It would have slowed the subject Tu204 markedly, perhaps saving everyone. The Runway is definitely non compliant per FAA, not that FAA regs should obtain here.
I would repeat my observation that 01 is "too long". Runway that should be overrun is not runway. It is overrun, and cannot (should not) be represented as usable runway for purposes of flight planning....
With great respect.
Last edited by Lyman; 3rd Jan 2013 at 07:48.