I haven't seen anyone directly address it in the comments here (or in the video): was an audible sonic boom noticeable on the ground during today's test flight?
this plane doesn't look like it was made to produce a low boom. It has a very distinct von Karman ogive [1] fuselage and typical delta wings. I would guess that it's shape is primarily optimized for fuel efficiency at 1.5 mach or above.
If you take a look at NASA's low boom demonstrator [2], you can see that it's much skinnier and the nose is crazy elongated. This is intended to break up the bow shock into multiple parts, thereby decreasing the amount of energy each one has.
Silly question, but would it be feasible to just equip a plan with a telescoping nose merely for this effect that could be deployed prior to supersonic flight?
Given that they were only authorized to fly in the "Bell X-1 supersonic corridor", I'd wager that sonic booms are fairly commonplace there. I doubt there are any residents around.
There are residents for sure in that corridor, but the residents are on Edwards AFB, and are fairly used to sonic booms. When I was on Edwards, there was still the last operating SR-71, and that boomed any time it flew.
>However, in the first 14 weeks, 147 windows in the city's two tallest buildings, the First National Bank and Liberty National Bank, were broken.
If a sonic boom is "noticeable", that's one thing. But the problem is that even from cruising altitude they're shockingly loud. If the sonic boom is merely bearable, that's quite an improvement.
With planes being long enough away from the demonstrator, and speed of sound relatively low (about 330 m/s), the booms of all three planes should be separate enough, e.g. a good 100 ms away from one another, even if all three went supersonic and were dragging their respective shock waves.
The distance between the planes appeared to be around 30-50 m at the supersonic transition time, as much as I can estimate the size of the planes. A sound recording made under the flight path should allow to measure how many dB was the demonstrator's boom.
Right, and making an improvement is a big part of Boom's marketing. (It's in their name?!) I'm surprised I didn't hear them make any comments about it in the video during the flight as they crossed the sound barrier each time. Unless I missed it?
No, it's the whole point of Boom. They won't be able to keep the sonic boom a secret. They whole company's future hangs on making that sonic boom minor enough that supersonic flights will be allowed with few restrictions. Therefore asking what the boom was is perfectly fair.
Now, Boom might say (have they? I'm not following them) that the XB-1 is a demonstrator that they can do supersonic flight, and that the sonic boom reduction work will follow on. In that case asking what today's boom was is not that interesting.
The chase planes also went supersonic, so they would have contributed to the sonic boom, which might complicate that analysis (well, there would be at most 3 pairs of sonic booms, and it should be possible to tell which ones correspond to which planes).
