This is the second time I've seen Kagi referenced with their summariser. It looks super useful, and the fact their summary references their points is just spectacular.
My only concern is around running out of searches with their basic plan.
mistersheep
joined 1 year ago
The ground noise is expected to be around 60 dB(A), about 1/1000 as loud as current supersonic aircraft. This is achieved by using a long, narrow airframe and canards to keep the shock waves from coalescing.[4] It should create a 75 Perceived Level decibel (PLdB) thump on ground, as loud as closing a car door, compared with 105-110 PLdB for the Concorde.[5] Wikipedia
Cool. A car door closing is far more acceptable than thinking you're being bombed. But yeah, the nose on it is really long. Considering that this experimental craft can only carry a pilot, any kind of passenger craft using the same technique would have to be absolutely enormous.
You're right that we have precise ways to say this, but people like seeing bigger numbers rather than smaller ones, and most people aren't "precise" about anything.
It's a relative metric, not an absolute one. And since they're using the word "lighter" (i.e. less massive) it means that they're talking about the reciprocal of mass.
I.e. 1/5 the mass = 5 times "lighter"
If something is 50% the mass of something else, you could say the the heavier one is twice as heavy as the light one. Which means that the light one is two times "lighter" than the heavy one.
But I agree with your sentiment, relative comparisons of reciprocals is confusing at the best of times.