Talk:2743: Hand Dryers

The mouseover text is trolling, since that would be impossible. 172.70.200.140 16:23, 27 February 2023 (UTC)

Indeed, Randall wrote about that in How To 2. Nitpicking (talk) 03:49, 28 February 2023 (UTC)

The Pratt & Whitney J58 is capable of producing exhaust velocities exceeding that of Mach 2 at ground level. It would be possible (though extremely inadvisable) to dry one's hands in the exhaust, at least for the brief period where one still has hands. 172.70.115.72 16:44, 27 February 2023 (UTC) J. Kupec

With a low enough vacuum in the surrounding area, a supersonic hand dryer should be able to apply drying without enough energy dissipation to damage the skin. 172.69.65.184 17:27, 27 February 2023 (UTC)

As far as I understand it, the low velocity dryers heat the air, the high velocity ones don't, but rely on the air being compressed and air speed is of the essence. The other problem with the idea of very high speed is that 'stuff' could penetrate the skin (there is a type of needle-less vaccination gun on that principle).RIIW - Ponder it (talk) 19:31, 27 February 2023 (UTC)

That matches my memory, the first ones I remember were fairly low airspeed and had a data tag "1500 watts" for the heating element. Has anyone tried one of these with *dry* hands, to see how long the element takes to get hot? I don't think they heat up instantly. They certainly get hot--motorcycling on cold days I've pointed the nozzle inside my clothing to warm up at a rest stop.172.70.111.76 19:40, 27 February 2023 (UTC)

I don't think this effect fully explains observations. For example, the airflow feels warmer sooner when someone has used the dryer just before you. P₁h₃r₁e₃d₁₃ (talk) 21:10, 27 February 2023 (UTC)

"though this was first achieved many decades ago, in the 1950s" Yeager broke the sound barrier in level flight on Oct. 14, 1947, and planes had been doing it in dives for years. Cser (talk) 21:29, 27 February 2023 (UTC)

Without reading your comment, I further changed the (as it was for me) "1940s" version of the statement to include the original "inadvertent" barrier-breaking (of prop-planes in almost always irrecoverable dives, without control surfaces that would work well in supersonic/transonic airflows) and included the developments made, which these days are somewhat more trivial than having to sit on a rocket that is released from a high-altitude bomber's wing, and fight to keep it flying straight and level. (We even had a supersonic airliner, for several decades!) There's a lot of interesting history to this, but not really the place to say it all. 172.70.85.57 01:45, 28 February 2023 (UTC)

Should we make an "airplane banner" category? 172.70.111.76 02:31, 28 February 2023 (UTC) I was thinking the same thing, but I'm here about Covid (below).

Hand dryers were disabled in the early days of Covid in 2020 before hand transmission was ruled out as significant. I still feel awkward using one in a bathroom with others. I'm old and still mask when indoors publicly more than briefly. In 2023, I submit that you risk appearing hypocritical with a mask and a hand air dryer. Thus, I saw this XKCD as a reminder that hand air dryers had nothing to do with Covid. Still, there seems to be a bunch of fuss about the dryers. Apparently, some use mechanical air force (jet air) more than warm air for drying, from respectable gavi.org and wired.org in 2021 (https://www.gavi.org/vaccineswork/we-know-hand-dryers-can-circulate-germs-through-air-why-are-they-still-used and https://www.wired.com/story/wash-your-hands-but-beware-the-electric-hand-dryer/). I'm just rambling here; I'm not ready to do any editing. Bismuthfoot (talk) 04:16, 28 February 2023 (UTC)