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Rockwell Collins To Develop Cockpit Display To Show Sonic Boom Over Land
An anonymous reader writes: Under contract from NASA, Rockwell Collins is developing equipment to let pilots of supersonic craft know where a sonic boom will be produced. The hope is to make supersonic flight over land practical. Flying higher widens impacts but lessens intensity. “In order for supersonic travel over land to happen, pilots will need an intuitive display interface that tells them where the aircraft’s sonic boom is occurring,” said John Borghese, vice president, Advanced Technology Center for Rockwell Collins. “Our team of experts will investigate how best to show this to pilots in the cockpit and develop guidance to most effectively modify the aircraft’s flight path to avoid populated areas or prevent sonic booms.”
... now the pilots can aim the sonic boom to hit the area where their mother-in-law lives....
becasue you love peace and quiet, well screw you. Is it ok to hit folks in low population areas with a shocking, loud noise. Helpful hint: NO, it is not.
"He took a duck in the face at 250 knots." -- William Gibson, Pattern Recognition
becasue you love peace and quiet, well screw you. Is it ok to hit folks in low population areas with a shocking, loud noise. Helpful hint: NO, it is not.
Sonic booms and noise pollution - well all pollution - should be where it rightfully belongs; in poor people's backyards.
Also the sonic boom issue was more FUD by Boeing, Douglas and Lockheed than the real issue. Back in the 80s, before the oil crisis, these companies wanted to stop British Aerospace and Aerospatiale from establishing a bridgehead at the luxury travel sector using Corcorde and its derivatives. But thankfully the Arab oil shock stopped Concorde.
Think about it, the total energy of all the shock and sonic boom is equal to amount of jet fuel burnt. During cruise at Mach 2.05 each Olympus 593 was producing around 10,000 lb of thrust, equivalent to 36,000 horsepower per engine.[18] Two engines, 72000 HP. Or 54 kilowatt, or 54,0000 joules/sec. If all of it ends up as sonic boom, (neglecting skin friction) you are going to spread 54,0000 joules every second over several square miles. Compare this to peak solar radiation 1000 joules per square meter. OK that is purely thermal but this is mechanical. So let us take 10 mph wind. 16kmph. 4.44 m/s. Over 1 sq m cross section, mass flow rate is 4.44 * density of air/second. Air is 1 Kg/m^3. So it is 4.44 kg. 4.44 m/s velocity. Works out to kinetic power (power, not energy because we are using mass flow rate, not mass) of 0.5*mdot*v^2 = 22 joules/sec. This is per square meter. or 22 watts per square meter. 22 million watts per square kilometer. Let us round it up to a nice 100 million watts for several square kilometers. Compare that to 54 kilowatt, total maximum possible power output of those two turbojet engines. 100,000 kW for 10 mph wind vs 54 kW for Concorde. Our eardrums and instruments are sensitive enough to pick up the sonic boom over 10mph wind, but thats about it. Barely detectable. Sonic booms deafening people, cracking buildings and killing birds are all FUD.
But cost... That is no mean thing to solve. In supersonic flight the energy needed to overcome the drag created by the shock wave is so high, there is no easy way to reduce the energy consumption. Only way to bring down the cost is to bring down the cost of fuel. The only way to make fuel cheaper is for the world to switch to non-fossil fules in such a large scale the oil industry collapses and oil falls to something like 5 dollar a barrel ( 2015 dollar not 1978 dollar).
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
âoeOur team of experts will investigate how best to show this to pilots in the cockpit and develop guidance to most effectively modify the aircraftâ(TM)s flight path to avoid populated areas or prevent sonic booms.
Yes. On Sunday it will do this. But Monday thru Saturday this technology will be used to test methods for waging Cymatic Warfare... in which fighter planes slave their autopilots to a central computer that flies them in passes towards a target zone from several vectors, such that the sonic boom interfaces-to-ground converge at the same instant. We have yet to see what might happen as standard building materials are subject to this type of harmonically amplified sonic energy. By Saturday afternoon we'll know.
Because there is no such thing as a single-use technology.
<blink>down the rabbit hole</blink>
Your prodigious display of math is all for naught since you've essentially proved 1=2.
I grew up in the early 60's when sonic booms were part of the background along with Duck and Cover. Nuclear war was just around the corner, or so we thought, and jets routinely generated sonic booms. Sometimes they'd sound like distant thunder and other times they'd rattle the house. Those were far louder, and more objectionable, than your putative 10 mph breeze.
Thankfully, they tapered off towards the end of the 60's as the Air Force realized people *really* didn't like being rattled and those same people objected to Congress. Since the later controlled the budget, the Air Force cut back on high speed overflight over the cities.
Booms weren't just domestic issues. NOVA interviewed a British Consul who was sitting in a tent in the Middle East discussing trade issues with his Middle Eastern counterparts. The Concorde flies overhead and the resultant boom startled all the conferees. The Consul said one of the men pointed at the sky and said "Concorde." at which point the Consul realized another trade issue had just been raised.
Some of those booms were anything but quiet and they sure weren't FUD as you assert.