What might my Dad have done in the 8th?

Please help me understand what my father's role in WWII might have been.  My mother recently shared with me that he was with the 8th Army Air Force and was stationed in the UK.  I was 16 when he died of lung cancer.  We didn't talk about the war so all I have are a few pieces of memorabilia and Mom's limited information about his service. 
 
I have a postcard booklet (fanfolded comics) of Army Laffs he sent to my mother, his girlfriend at the time.  The postmark shows it was sent from Tucson, AZ, but I cannot read the postmark date.  It appears he was on his way to training in Miami at the time.  He wrote the following (caps, punctuation and spelling are his),
 
PVT. STERLING E MANESS JR
ROSTER 178
CO. B
FT. MAC AURTHUR CALIF.
AM ON MY WAY TO MIAMA, FLORIDA    LOVE XXOO
ARMY AIR CORPS ORDINANCE
 
I know he was not a pilot.  Mom said he helped unload wounded and dead and cleaned up afterward.  A photo I have of him shows him with a tire on the ground and it appears he was repairing it.  I always assumed he worked on the planes.  
 
I also have a photo of nose art, but the "name" is cutoff as the intent was clearly to show the dark haired woman wearing a sheer blouse & skirt with a bold bra (and a girdle, I think?) showing through.  The photo is dark and difficult to see the detail.  It reads "PATCHI" and her ankles are in between the T and C.  The text on the side shows U.S. ARMY B-24H and there appears to be a crudely written serial no. 42-295219WW below it as the painted woman hides the official looking serial number.
 
Some of the men he may have been associated with:
I have a photo of men with the following names shown on the photo:  Hall, Shade, Mac, Potter, and Malone.
I have a photo of one man with the name Murray.
 
I have his dog tag (by the way, does the "P" in the lower right of the tag indicate his rank (Pvt?)? 
 
Any help is appreciated.  We weren't a "military family" so I know virtually nothing about the Air Force and had no idea it was part of the Army in WWII.  Please forgive my ignorance.  I spoke with Mom and shared that my daughter is preparing to go to MEPS soon.  That 's when she told me about Dad's connection to the 8th.  I always thought he was just an Army guy. 

Oh my goodness!  I can't thank you all enough for your posts and quick responses with links to more information.  Your enthusiasm for sharing your knowledge of WWII history is very appreciated. 

Folks:
I just wanted to add my thanks for everyone's speedy responses to Sonya.  You guys are great!

Genuine thanks to all who have posted.  I never imagined so much information in such a short time, especially the links and contacts and research you have done.  I am grateful for it all.
 

Kevin:
Thank you!  The photo of Patchie is one I have not seen before.  (CORRECTION - I do recall having seen the photo on the b24 site in the link, now that I think on it...had forgotten it, but one of the members above had posted it.)   I have learned through the help provided by this forum that my Dad was a member of the 459th Sub Depot.  He probably repaired some electronics on Patchie and must have thought the nose art worth a photo. 
 
Your uncle is a smart looking young man.  You must be very proud of his service.  I was not able to open the Library of Congress link, but did manage to search the site to find your uncle's interview.  I will listen to it. 
 
Thank you for sharing and, more importantly, thank you for your service.