Bessie info here for what it's worth, being no car expert myself. http://freespace.virgin.net/dr.dean/
As was depicted in "Parting of the Ways" with Rose and a Dalek guarding her, simply materialize and dematerialize the TARDIS around Bessie. But since the last time we saw Bessie (relative to the Doctor's time-line) was in BattleField, the Brig probably had it stored for the Doctor whenever he should return. Sincerely, Bill
^ If that's the case, it's a shame Kate didn't mention Bessie in The Power Of Three. "Dad kept something just in case you came back"
Love the idea of the Doc visiting '70s-'80s UNIT. He'd have to make sure to tell them "if the other bloke you know comes back around, don't tell him I was here". As for cars, they really need to bring back the Whomobile, cell phone and all. WHAT a contraption.
When the doctor left unit the brig put bessie in storage in case the doctor ever needed her again(battlefield), like to see the whomobile again.
Well, now that the Sarah Jane Chronicles are over, we could use a kid-friendly Doctor Who Spin off. Imagine: The Bessie Files Bessie is given an AI program of some kind and has kids run around solving mysteries with her. But get this: All of the mysteries involve aleins! And maybe Bessie can go through time or something. Also, Bessie gets a regeneration sequence in the first episode after being shot down by aleins of some sort.