NASA appears to be desperate to find a way to get Americans to accept sonic booms. Their mission now? How loud can they be all day long before people get really pissed off?
@lauren IIRC the original research on sonic boom tolerance was carried out in the 50s and 60s by the USAF with military jets overflying towns at low altitude on afterburner.
But really, this won't lead to supersonic airliners. It'll maybe give a few dozen oligarchs a 50% faster bizjet: that's all. (There are good economic reasons we don't have SSTs or sub-orbital passenger rockets, regardless of whatever white powder Dilbert Stark is huffing right now.)
@lauren They were tiny! (If there's one in a museum near you, go walk through it: they're 2+2 seating on either side of the aisle, and it's like a cramped second class regional jet for leg/elbow room.)
I was once on a plane taxiing for takeoff behind a Concorde at JFK. It was louder than we're used to in the 21st century, but surprisingly quiet by 1960s (pre-hush-kit) airliner standards.
@lauren I'm still bummed that they retired Concorde the year I finally had enough money to pay for a single joy-ride for myself and my wife, and all the seats sold out before I realized.
@lauren Drag increases nonlinearly with Mach number, but there's a local minimum around Mach 1.5, +/- 0.2. Concorde went for Mach 2.2 speed (with four time the fuel burn of flight at Mach 0.9). Newer proposals are aiming at Mach 1.3-1.5, with supercruise (no afterburners needed), while regular airliners cruise at 0.85.
But Concorde needed 72 hours of maintenance between flights: it was only viable for LHR/JFK traffic. There's no point going faster if you have high inter-flight latency.
@cstross@lauren If “boomless” planes work out, even those lower supersonic speeds would greatly enhance domestic flight times for larger countries. And hopefully engine tech (and other maintenance items) have progressed sufficiently to make turnaround much much faster.
@michaelgemar@lauren Disagree. Crossing the USA in 4 hours instead of 8 hours sounds nice, but if there's only 1 flight per day it means cutting travel time of up to 32 hours to at most 28 hours. (That's the latency problem.) If you're a gazillionaire with a supersonic Bizjet it's another matter—the jet leaves when you're ready—as long as it's not permanently in the maintenance hangar. (Concorde was really reliable compared to military fast jets. But a working SSBJ needs to be far better.)
@Sdowney@lauren Concorde was about as loud as a 727 or a first-generation (no hush-kit, turbo-jet powered) 737-200. (Hush kit requirements made airliners a LOT quieter from about 1972 onwards. Concorde wasn't unusual for its time, except when on afterburner for take-off and transsonic acceleration. And of course the sonic boom, which is why it was banned from going supersonic over land.)
@cstross@lauren I remember reading how some big-name movie director was shooting a film on one side of the Atlantic while another film was being edited on the other side. So some minion flew the edits over every day by Concorde.
@timbray@lauren During the 1980s and 1990s banks used to courier magtapes across between London and NYC every day by Concorde—trading ended in London 5 hours before end of business in NYC, Concorde took 3 hours to make the flight, so there was a significant window (back when a trans-Atlantic leased line cost A LOT more than a daily Concorde ticket).
@danmcd@Sdowney@cstross@timbray@lauren I don’t think I personally ever used the 7-track tape drives on the systems I used, but they were there. Well, maybe I did—the machine I learned programming on had a tape-resident OS and compiler and 24-bit words, so it was old enough for 7-track tapes.
@stark@mark I disagree. They're nasty if you have to deal with them frequently. And in a commercial context, they're all about the ultra-rich. To hell with that.
We used to get sonic booms here in my corner of L.A. when the space shuttle landed at Edwards Air Force Base. Infrequent enough not to be a big deal, but still annoying.
@randulo That's what NASA is trying to do, and there are other efforts. They probably can reduce the noise level, but getting rid of them entirely is a pretty tough exercise, given, you know, physics.
@lauren@randulo I don't understand why this is a priority for them. Now, if they wanted to fund R and D for planes that don't emit vast amounts of CO2, rather than planes that produce even more CO2 than conventional planes but shave an hour or three off the flight time, that might be worth doing.
@lauren Yes, the NASA Space Shuttle caused sonic booms over LA on its way to landing at Edwards Air Force Base in Palmdale. I believe that 1985 was the year they flew the most times, 9 times that year, with 7 landing at Edwards.
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