Sikorsky CH-54A Tarhe, s/n 66-18410, new to US Army in 1967. Later in civilian life a S-64A Skycrane, N6156U, Tanker 790, used for fire fighting missions flown by Heavy Lift Helicopters, Inc. Carrys two tanks, two doors on each tank, with total capacity of 2,600 US gallons. Shown here at the Prineville, Oregon, airport (PRZ/S39).
<a href="//commons.wikimedia.org/wiki/User:Tequask" title="User:Tequask">Tequask</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>