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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
I think they're developing it so the Israelis will be able better able to piss off the Palestinians.
Don't know what it was, precisely, but there was a long rumbling roar, followed by a period of noise that caused all the windows to vibrate.
Then the news later said the Air Force had been doing some tests. I don't know where the nearest site was, but it must have been at least 20 miles away.
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.
Why not just fund ways to prevent it?
A sonic boom is just a concentration of waves that cannot move out of the way quickly enough.
Current research on anti sonic boom tech seems very low for some reason.
Seems strange considering it would be a huge advantage.
Besides the concepts that have been tested with shapes, you could possibly even create deliberate interference that would eliminate a lot of the energy of the wave by making it spread out more evenly.
Seems like something which could be done by a 'back room' computer when the flight path is being generated. At that point, you could modify the flight path to put the sonic boom where you want.
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>
Santa sued Air Force for killing his deer Rudolf
About 10 years ago or so.
I am very small, utmostly microscopic.
So Sonic Booms are okay over unpopulated Areas? I guess those wild Animals are immune to any negative effects.
Tell pilots how to avoid populated areas? And where in the U.S. do such areas exist? True, areas vary in how densely populated they are. But there's no NYC-LA route that won't irritate many millions of people.
No, unless someone can create sonic boomless aircraft, it's not right to irritate millions of people, pets, farm and wild animals just so a 100 or so people can knock a couple of hours off their cross-country flight. Create a super-first class for them in sub-sonic planes if you want, but leave the rest of us in peace.
This is a stupid idea (unless the summary is grossly in error, which is possible). Since pilots can't arbitrarily change their flight path, knowing where the sonic boom is going to fall is useless. You need to pre-plan the flight path.
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.
There was a breakthrough a few years back where they found how to prevent the bow shock from forming in the first place. Did that die in R&D?
A device in the cockpit to tell the pilot where to go, so as to minimize sonic boom impact? This is a one-time job, map out good regions to fly through, done.
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He makes a lot of assumptions. I, for one, would love to go back the internet before the ads (yes, I am that old!) I would gladly see all those ad-sponsored services go away or transform so that we don't need them. I'm not the only one who feels this way.
I live between a couple of air force bases. Between, not real close, probably 100 miles from each one so while not frequent occasionally there will be some low flying military jets or helicopters going subsonic over my neighborhood.
They can be incredibly loud and disturbing. If sonic booms as described by some here are no worse than thunder then I don't see a big problem.
If those military flights were regular and/or frequent I would be annoyed. As it is now I am just curious if it's worth it to run outside to see what is buzzing my home before it goes away.
Besides, I've always liked the sound of thunder. Also having lived near train tracks a few times you really do get used to such frequent noises.
...by more people than you can imagine. Right now there are researchers around the world looking at all aspects of aircraft and helicopter noise. Within the engine itself, there are at least four engineering sub-disciplines (fan noise, combustor noise, jet noise, acoustic liners) looking at ways to make them quieter. Progress during the jet age has been extraordinary with aircraft noise levels dropping by a factor greater than 10 (http://www.fly2houston.com/NoiseFAQ, scroll to the bottom for a chart). NASA's stated goal is to get noise down to a point where you won't hear planes once they've left the airport area. Granted, this is an optimistic goal, but the enabling technologies are being developed right now and if a good number of them make it into production, things will get a whole lot quieter.