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Supersonic biplanes: More fuel efficient, quieter sonic booms

supersonic biplanes does seem plausible, wonder where this avenue will lead if anywhere? i know there was an F-5 if i recall highly modified with a rather large 'chin' and telescopic 'probe' on the front to see if breaking it sooner using the probe and bulbous chin would result in a smaller noise footprint... amazing even now to think how far we've come in the 109 years of manned, powered flight...

and from what i recall of physics, where the shock cone is visible in that video is called the Prandtl-Glauert singularity, best way to explain it is actually the Wikipedia entry...

"The Prandtl–Glauert singularity is the prediction by the Prandtl–Glauert transformation that infinite pressure conditions would be experienced by an aircraft as it approaches the speed of sound. Because it is invalid to apply the transformation at these speeds, the predicted singularity does not emerge. This is related to the early 20th century misconception of the impenetrability of the sound barrier."

basically,
The white halo consists of condensed water droplets formed by the sudden drop in air pressure behind the shock cone around the aircraft, even so the conditions have to be right, humidity, pressure, elevation for it to appear, by the 'cloud' appearing you can sorta see where the shock cone is on the aircraft... behind the aircraft it wouldn't really be seen as there's nothing disturbing the flow, and as we all know that cone is where the sound barrier sits, when you 'outpace' (for lack of a better word) the cone you're travelling at a speed equivalent or above Mach... or that's how i recall it being explained :icon_lol: memory's a bit hazy at the moment :icon_lol:


 
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