"Both the Ks, however, managed to soldier on nicely"
I'm under the strong impression that the Chinook is lifting far more than the 'k' is in Afgan and that the 'k' decided to clip a sand dune on a departure from a strip as it could not get airborne due to performance issues....
As for reliabilty, how many 'k' frames are actually working and doing a job? I'm not talking about flying around Wilts either(no need to post the answer to this,but the answer is obvious)
I standby to be corrected.