STEVE INSKEEP, HOST:
Good morning, I'm Steve Inskeep. In the movie "Airplane II," doors open automatically with a woosh (ph), and the password is for a person to make that wooshing sound.
(SOUNDBITE OF FILM, "AIRPLANE II")
INSKEEP: German scientists now want you to open doors with a sound, and you don't have to even make it. An ultrasound signal would bounce off your head. It would note the special way that your skull vibrates in response.
LOURDES GARCIA-NAVARRO, HOST:
What if you have a head cold?
INSKEEP: Well, then you go back to saying woosh-woosh. You're listening to MORNING EDITION. Transcript provided by NPR, Copyright NPR.