Winnie, I don't know who you're talking to, but they're talking smack!
The 139 loves the cold. Ask Alaska and Kazakhstan. Especially Kazakhstan. Those things used to freeze in an unheated hangar (-25 inside), but they would be wheeled outside every day and go flying with no problems (-30 to -40).
I think the record was 52 flights in one winters day with the 5 AW139's and a dispatch rate per month approaching 95% in what I would call a very harsh winter climate.
Then the poor machines would be subjected to +48 in the summer at the same base. That is an 88 degree Centigrade difference and it all just kept working.
The biggest problem seemed to be with Fuel valves freezing up, but a thump got them working again
