This model is a version of S-56 H-37
Helicopter Sikorsky H-37A Mojave Serial 56-073 Register 55-638 used by US Army Aviation. Built 1958. Aircraft history and location
| US Army Aviation |
|1958-03-10||Sikorsky S-56, c/n 56-073, ff:?|
del US ARMY as H-37A, 55-638, 10Mar58
redesig CH-37A, Oct 62
conv CH-37B, unk
wfu & soc unk.