This thread has stirred some old memories vis a vis Army fixed wing aviation.
DeHavilland of Canada built two light cargo aircraft during the Viet Nam war - the Buffalo and the Caribou. As I recall, they were initially Army aircraft, but the AF won a political tug of war and got the aircraft transferred to the AF. I also recall that the AF actually used the aircraft to some benefit in Viet Nam, but after the war, they were promptly sent to AF Reserve and Guard units, where they rotted on the vine.
Other than light utility aircraft (from Beavers and Otters up to and including Beechcraft King Airs), the two most successful Army fixed wing aircraft I can remember were the Grumman Mohawk OV-10, used in Viet Nam, and the Short Skyvans that the the AF used for a short time in Europe and then gave to the Army to use for a few years.
Here's a link for the Mohawk, probably the most significant, and effective, Army fixed wing aircraft since the AF was formed:
http://en.wikipedia.org/wiki/Grumman_OV-1_MohawkIn my second career (NWS Doppler weather radar tester) I got to spend several extended business trips in Enterprise, AL, which is near Ft Rucker.
Not much to do in Enterprise (or anywhere else within a 50 mile radius) on the weekends, so I enjoyed visiting the Army Aviation Museum at Ft Rucker. It's not very big, but has some really neat displays.