I'm not sure what you are reading but I don't see any equity buyback.
You may have read this? :-
News - CHC Helicopter
but that is simply it buying its own debt, the tradable equities in CHC are now broadly tracking the price of crude, but remain as depressed as ever - the stock closed at $1.24 and actually its not really traded that widely because liquidity is very poor in the name (for example it traded $500k worth all day yesterday).
What is the most concerning thing about this name is that its operating in an environment that is in a current downturn with an executive whose longest tenure is 1.5 years and Joan Hooper the CFO (Chief Financial Officer) holds a total of 80k shares and it would seem most of those come from options due to an employment contract! So that's how much she believes in the stock - her current disclosed compensation for 2014 was $1.7mil and she holds $107k of CHC common equity.
Joan if you believe in your company buy the stock!