Special Duty?

I've been wondering about that, too! While I haven't figured out the complete answer, I've made a few educated guesses.

I think the "Burbank potatoes" was him deliberately obfuscating the real nature of his work. I've read that even some of the civilian government girls had to keep their occupations secret from their roommates if their jobs required higher security clearance.

Burbank was then home to Lockheed Air Terminal (now called Bob Hope airport). During the war, they covered the main factory with netting and disguised the airfield to look like farmland.

http://www.lockheedmartin.com/us/100years/stories/camouflage.html

So I think we can presume that Joe's job involved aircraft--possibly engineering, given his status as a non-commissioned officer. And I presume that "Special Duty" means Special Ops of some sort. But I'm no military expert. I'm sure if anyone who is happens upon this page he or she could set me straight.

He said he was working on sending babies (bombs) to Tokyo, so probably something related to bomber craft.