Blanketing a Twin Otter's engines in Thule Greenland.  In the far north engines can rapidly get too cold to restart.  The blankets help the engines retain enough heat to be restarted for the return flight.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/78042080@N00">Erik Charlton</a> from Menlo Park, USA
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/78042080@N00/332142723/">Thule Greenland</a>