Heh, I knew that posting "I can't find blah" would work:
"This Will Never Work" Attack of the Hawkmen
DVD Time Index 0:03:19
From Young Indy DVD Game: Special Delivery: medcamp-1 @ 0:17-1:48
This is the first of the DVD game tracks that is split. Hawkmen never had a bookend, but was the intro more abrupt in the TV airing, perhaps? That preamble does sound a lot like Vienna 1908 though...
PS: Does anyone find this dialog from London 1916 very unsettling?
Indy: "Is that a Zeppelin?"
Vicky: "No, it's a time-traveler from the twenty-first century coming to see if we're all right."
I mean, sure, Vicky is well read and everything, but the potential for conspiracy theories from that line is astounding. If you discount the bookends, you could imagine quite the fanwank story there.