it so well, is the set of circumstances and the ability of the crew flying that day to meet those circumstances. this was a short flight, only 55 minutes or so, takeoff to landing, so it's not going to get very high in terms of altitude. it's going to be in the descent before you know it. and there were mountains in the regions, some up to 13,000 feet, and there was bad weather. now, in that environment it is -- these pilots fly those routes frequently, but they are challenging conditions. especially if, as les says, there was no landing guidance systems available to them. if you look at trigana as an airline, as i said previously, it's got about 14 previous incidents. some are serious, some not so serious since 1992. which is quite a number, frankly. it's quite a number.