The plane wasn't sabatoge they clearly point out that at the time that Desmond didn't enter the numbers in time cause the plane to be pulled out of it's course and broken up. Not sure which episode it was but they had found some printout of everytime the numbers were enter, and Desmond compare the time when he wasn't there to the time of the Losties coming to the island.
One says EKKO, another says ELKO, yet another says EKO and I thought when he first appear on the show some said he's ECHO. It does kind of crack me up when I seen some spell a name one way and another another way. I'm not a perfect speller myself. I'm a deaf person and I depend on the closed caption to follow whats being said on television shows. I get upset if one of the programs I enjoy watching and there's no cc coming up on the screen or it comes on/off later in the program. I've sent emails to the station pointing out to them that the program I was watching about the problem with the cc signal, I've been told okay we'll look into that. I once knew of a site where I use to go to and they would post the cc from each episode of Lost, my computer crash and I could never find that site again. So if anybody out there knows of this site please send me a message I'd would like very much to have it back in my favorites.

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Standing in the ocean with the sun burning low in the west
Like a fire in the cavernous darkness at the heart of the beast
With my beliefs and possessions, stopped at the frontier in my chest
At the edge of my country, my back to the sea, looking east