Subtlety is not heavy metal's default position; never has been - neither in its musical output or, indeed, its cover art. When UK hopefuls UFO approached Hipgnosis in 1975 for sleeve ideas for their new album it was the firm's crack design team, led by Storm Thorgerson, that came up with the initial idea. Thorgerson and co. then proceeded to absolutely throw the kitchen bathroom sink at it. Literally. The band wanted to call the album Force It, so Hipgnosis gave them taps (geddit?), and lots of them.
In the UK it was released as the band intended. Sexual politics aside, it's a non gender specific couple seemingly getting it on in the bath. But the Americans wouldn't stand for such shenanigans. On its initial release in the US the offending protagonists were airbrushed out totally (with a shedload more taps added) and then subsequently replaced by the band's guitarist Michael Schenker (though not, unfortunately, in the bath).
I heard today about the passing of Storm Thorgerson aka Mr. Hipgnosis. He's obviously best known for the iconic sleeve design of Floyd's Dark Side of the Moon (and quite rightly too), but his canon goes far deeper than that. When I wrote a Sleeve Notes piece for Classic Rock magazine a few years ago, remembering UFO's Lights Out album cover, I grabbed a few words from Storm as well as interviewing Phil Mogg, the band's vocalist. Mogg was typically vague, only remembering two geezers (him and Michael Schenker) wearing overalls in Battersea Power Station. Thorgerson on the other hand, while admitting it wasn't the best cover they did for the band (try Force It - the one with the taps) saw a sleeve not without a certain charm: 'where vanity meets industrial design.'