Back in the 1970's, I rode in the gondola of the Goodyear blimp a few days before the Indy 500. We...slowly...floated around Indianapolis and I remember how actually quiet it was even when the propeller was running. The pilot told us a story about a drugged-up guy who tried to hijack on of the blimps once out west and demanded to be taken to Cuba. Apparently, he wasn't in a big hurry....