Are you serious? I've never heard about a relief tube in one of those ole birds. I thought that was only for large a/c that you could walk around in.
I wonder why the cockpit comm tube only had a funnel on one end. I guess the guy up front would have the most trouble hearing. So in my opinnion, the funnel would be in the rear cockpit.
The following quote was from a site, listed below.
Student pilots occupied the front cockpit, while the instructor sat in a rear cockpit with identical controls.
http://www.collingsfoundation.org/ma_pt-17...earman_hist.htm
That was pretty typical for most trainers of that time.
US Air Force Museum site:
http://www.hill.af.mil/museum/photos/wwii/pt-17.htm
Intesting that their PT-17 was found in Mississippi living the life of a crop duster. When I grew up in the cotton fields of Mississippi, the stearman crop duster was a common site. Maybe you could write these guys and get an answer.
Or try Aviation Enthusiast which has are to upload comments - at
http://aeroweb.brooklyn.cuny.edu/specs/ste...arman/pt-17.htm
Here is a link about WASP pilots and their problems with relief tubes and where to carry their make-up kit.
http://www.marchfield.org/waspweb.html
BTW, I also found this little bit of info.
The Army models were PT (for Primary Trainer) -13, -17, and -18, depending on whether they had the 200 Lycoming, Continental or Jacobs radial engine. The PT-27, procured under the U.S. Army designation and serial numbers for Lend-Lease to Canada, was a special winterized PT-17 and was not used by the U.S.
Steve