Q; What was it actually used for? Navigation, or Navy communications on HF?
A: Woolywebbers were used for D, all the above.
Developed in ww2 Germany, these antennas had interesting capabilities in direction finding and sensitivity. After the war, the US and Russia in particular dismantled some and took them home. We built them in various places around the world to spy on friends and enemies alike, as well as take df fixes. A friend used to sit for hours in front of an R390A or two, listening to cw signals from Chinese or Russian air forces, said signals picked up via a woolywebber or rhombic antenna in Turkey, Viet Nam, or elsewhere depending on where he was posted. Oddly enough he hates cw but loves the R390A to this day.
Each service watches its counterpart, navy on navy, army on army, etc, and all the take was/is fed to nsa. The Russians and Chinese as well as others listen to our traffic too. Remote rx systems and sdr plus active antenna df arrays have largely done away with woolys, but there are still some in use, Germany still uses the one we gave them after we closed shop in Germany.
If one ever becomes a museum, I envision it packed with remote capable sdrs.
https://en.wikipedia.org/wiki/WullenweberIf you've not read these related tomes, you're welcome in advance;
https://www.scribd.com/doc/57791980/The-Puzzle-Palacehttps://cdn.preterhuman.net/texts/cryptography/Body%20of%20Secrets.pdfBonus reading material;
https://cryptome.org/2015/04/nsa-war-secrets-in-the-ether-p1-p2.pdf