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Comment by danielschonfeld | Hacker News Reader

I believe the problem with those was always the sonic boom created by flying at > 1 Mach. It shattered windows on the ground.

Could be wrong tho

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Most of that route would be over the Pacific, so it would be fine, too (although ex-West Coast US).

It might be a fuel issue on distance, but probably not. Also potentially an ETOPS range issue.

However, there are three big issues with transpac: (not impossible issues, but strong reasons why NYC-LON is ideal as MVP)

1) Greater number of destination cities on each side; for transatlantic, NYC-LON really is the main market. LAX-NRT is probably the best first pass. but LAX/SFO/SEA/LAS/Texas/NY/DC could all make solid claims on being sources of traffic, and there are >10 cities in Asia which would be destinations and fairly far apart? I'd almost certainly prefer a nonstop NYC-PEK to a domestic NYC-LAX, switch to LAX-NRT supersonic, then another subsonic NRT-PEK.

2) A lot of the good cities are inland, so no supersonic for those parts of the flights. NYC-PEK or NYC-PVG (corrected) would be awesome, but there's a lot of inland there. So you're also stuck doing something suboptimal, either connecting flights or operating outside supersonic regime.

3) After a certain point, comfort is a priority over absolute speed. If it lets you accomplish a mission (meeting, etc.) in a single day, that's a new capability. if it means you get 5h of cramped sleep and then another 7h of cramped sleep on the way back, that's not really better for most missions than 8-10h of comfortable sleep in a full-sized suite for the same price. There clearly is a value in 1-4h flights from USA to China/India, but that requires more than Mach 2.2 -- maybe exoatmospheric.

Another option is probably "events"; special flights to follow F1 and stuff like that. Concorde did a lot of that toward the end.

NYC-PEK or NYC-PVG would be awesome, but there's a lot of inland there.

A lot of really sparsely populated inland. How politically influential are the Siberian fur trappers this route [0] overflies? Enough to counteract the fat overflight fees that Russia likes to charge?

[0] http://www.greatcirclemapper.net/en/great-circle-mapper/rout...

You are right -- there would be a bit of extra subsonic about 150km into Canada, but it would work.

Flight time at 2.2 would still suck, but there could be a market. Probably depends on the total traffic between the city pairs, since some fraction would pay for supersonic coach-size business vs subsonic business/first.

I figured it took that far just to get to a suitable altitude. This isn't a King Air Beech 90 one can just keep cranking back while jamming the throttle. It was designed with very different goals.

Mythbusters tested the sonic boom myth. An F/A-18 flew ridiculously low (200 ft AGL) before the window cracked with a supersonic flyby.

A sonic boom from a fighter jet above around 10,000 ft usually doesn't break any windows. In one case, a General flew a F-22 in supercruise just off the Florida coast at over 50,000 ft and nobody "reported" the boom until the media story ended up on the news.

For low level supersonic flight, what typically happens is the pressure wave created either overflexes the window pane, or the window frame isn't strong enough and the glass falls out.

For a larger aircraft like the Concorde flying above 40,000 ft they wont break windows. People complain about the noise.

Supersonic flight is banned over populated areas. I'm not sure if it's from shattering windows or not.

Is there any reason you can't fly subsonic over land, then accelerate to supersonic over the ocean?

Supersonic-capable aircraft tend to be absurdly fuel-inefficient when operating subsonic (for aerodynamic reasons I don't really understand).

Grew up in Germany during the Cold War. Sonic booms from military jets were not rare. In the low level flight training areas the population really suffered.

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