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The B-52 and SR-71 had star tracking systems for that exact reason. Not sure about the B-52 version but the SR-71 worked in daylight.

https://www.glennsmuseum.com/items/b52_astro/

https://theaviationgeekclub-com.cdn.ampproject.org/v/s/theav...


I wonder how satellites affect that now. So many more by an orders of magnitude


They don't.

Cloud cover, OTOH, is a real killer-- but not a problem for high altitude aircraft.


That's my experience as well in 2 different companies where we went from 2 E15K to 2 E25K because it was "cheaper" than rewriting who knows how much code, for how long and at what cost

At the other one, we jumped from 2 25k to 2 M9000-64 for the same reasons...


Well Concorde showed pre-orders don't mean much... :-D


My take is it's not even an economic problem. Unless you fly really fast (like Mach 3++), flying east sucks.

Let's assume we have a plane capable of Mach 3+: the SR-71 holds a record for flying from NYC to London in 1h54 and it could do well over Mach 3. Let's assume our plane can do the same in 2 hours.

If you take off from NYC at 10am, you will land at 5pm local time in London. Sure it's a lot faster than a regular flight but you didn't gain as much as flying west bound.

With the same 2 hour flight (because when you fly that high, wind doesn't make such a big difference), you could leave London at 10am and land in NYC at 7am local time, that's so much better.

But that's for a plane doing Mach 3+. Boom is planning to fly slower than Concorde (Mach 1.7 vs Mach 2.02).

Concorde did that in 3 hours FYI.


I'm not sure why you're being downvoted because you're right: they have the technology, they don't have an engine, and this just looks like a civilian version of a fighter jet pretty much (except it has 3 turbojets).

And what people always fail to mention when it comes to supersonic flights is one of the main issue is neither a technological nor an economical one nor a supersonic boom one.

Traveling west bound is great: you leave in the morning and you arrive, local time, before the local time of your origin point. But traveling east bound isn't that great: you still have to leave in the morning and you land in the evening, so the only thing you gained is a shorter flight time but not a full day of work or shopping or what not.

So on regular flights (because Concorde was profitable, at least on the French side, thanks to charter flights), people would fly Concorde to go to NYC and fly back on a red eye...

As someone who worked for and flew on Concorde, I think what they're doing is amazingly cool though and I hope they succeed. But I'm still unsure what the long term plan is...


Right. Whether I arrive in London at 4pm or 8pm doesn't really make much of a difference. (Admittedly it probably lets you arrive on the continent without a red-eye--depending on supersonic over land rules--as you pretty much have to do today.)


I still prefer shorter flight time. I rather spend those hours in hotel bed or eating at restaurant than sit/lie in the airline seat.


All other things being equal, sure. But I'm probably not paying thousands of dollars to save a few hours. Maybe if that amount of money is basically pocket lint, but that's a tiny percentage of the population.


> I'm not sure why you're being downvoted because you're right

OP is being downvoted for saying there is still not supersonic civil aviation on a video showing a civil aircraft going supersonic.


You are right - (And it's not a civil aircraft just because it's painted white.)


Fair enough...


> they have the technology

Having the tech sounds funny. In some abstract way maybe. Actually being able to build a supersonic airframe and everything connected.


If you solve the boom component, can you just keep going West? London, NYC, LA, Tokyo, Singapore, Dubai, London?


Concorde holds the world record in both directions actually.

F-BTSD did it:

- westbound in 32 hours 49 minutes and 3 seconds on 12/13 October 1992, LIS-SDQ-ACA-HNL-GUM-BKK-BAH-LIS (Lisbon, Saint-Domingue, Acapulco, Honolulu, Guam, Bangkok, Bahrein, Lisbon)

- astbound in 31 hours 27 minutes and 49 seconds on 15/16 August 1995, JFK-TLS-DXB-BKK-GUM-HNL-ACA-JFK (New York, Toulouse, Dubai, Bangkok, Guam, Honolulu, Acapulco, New York)

https://en.wikipedia.org/wiki/Concorde_histories_and_aircraf...


This is correct, reheat / afterburner was used from Mach 0.9 something to 1.7, after which they'd were off. So yes, Concorde could supercruise.


As far as I know (source, I still patch the LTS kernels), the fan control of the POE hat for the Pi 4 hasn't been merged yet.

This thing was announced on May 2021...

So not so good is really an understatement.

https://www.raspberrypi.com/news/announcing-the-raspberry-pi...


At this point, probably never it seems...


And considering their effort in patenting every idea related to it, we’ll only see it when the first implementer gets sued.


The issue with (software) raid is you have no idea if what you're copying isn't actually corrupted. If the filesystem isn't checksumed there's no guarantee.


One can use software RAID5/6 to get the checksumming.


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