JULIE / JEZEBEL

What makes a passive buoy active?
Miss "Julie" Gibson, the namesake of explosive echo ranging technique.

I'm reading about the Grumman S-2 Tracker and the Wikipedia article mentions "Julie/Jezebel detection equipment", which leads to a page on WW2Aircraft.net, where I found this explanation:

THE LEGEND OF JULIE-JEZEBEL

May 27, 2005

In the 1950s the NADC (Naval Air Development Center, Johnsville, PA) was involved in the development of techniques to detect submarines.

One evening, between days of one of the program's technical reviews by visiting NAVAIR sponsors, some of the visitors took in the entertainment at The Wedge, a burlesque theater in nearby Philadelphia. A performer that evening was Julie Gibson, doing her "Dance of the Bashful Bride". The visitors were duly impressed, deciding that Julie "made passive boys (buoys) go active." OK, it may be kind of a lame play on words, but that is how they arrived at naming the program Project JULIE. JULIE was introduced into the Fleet in 1956.

JEZEBEL, the acoustic detection method using passive-listening sonobuoys, likely had its name inspired by Biblical reference. In Kings 1, Jezebel, a queen of ancient Israel, was nothing but bad. She was (among other things) "a Betrayer", and it was likely that idea of betraying the presence of an enemy submarine through passive acoustic detection that gave this technique its name.

Many Anti-Submarine Warfare aircraft were fitted with the AN/AQA-3 "Jezebel" acoustic search (passive sonar) and "Julie" echo-ranging (active sonar) gear.

More about Tracker to come, I hope.