Towards Silent Supersonic Planes 332
Roland Piquepaille writes "There is no longer a single commercial supersonic airplane since the retirement of the Concorde last year. And even during its years of glory, the Concorde was not a commercial success, mainly because it was not allowed to cruise at supersonic speed over land. Why? Because of the sonic 'boom' which arises when you break the sound barrier. Now, a joint program between NASA, the military and the aerospace industry wants to remove, or at least reduce, this sonic boom, by changing the shape of supersonic planes. It seems to work. After a 'nose job' on a Northrop Grumman F-5E, about a third of the pressure released when breaking the sound barrier has already been suppressed. This overview contains more details. It also includes a photograph of the modified Northrop Grumman F-5Ea aircraft flying off the wing of the F-15B research testbed aircraft. [Note: Previous results were reported here by Slashdot in last September.]"
Now (Score:5, Funny)
not the sonic boom (Score:3, Informative)
Wrong (Score:5, Interesting)
Fuel costs about $400 per tonne plus taxes.
You do the maths.
Re:Wrong (Score:3, Insightful)
Re:Wrong (Score:5, Informative)
I took a few minutes to demonstrate that the cost of fuel was not, in itself, an especially large component of the running cost of the aircraft.
ALso, BA's accounts show that the Concorde operation was profitable prior to the crash.
Re:Wrong (Score:3, Interesting)
Re:Also Wrong (Score:3, Informative)
Because there are much less airplanes than there are cars. If plane emissions ever start to get anywhere even NEAR that of cars, you can bet that they start to get taxed more.
Jet aircraft have done far more damage to the ozone l
Re:not the sonic boom (Score:3, Informative)
The Sonic Cruiser was a subsonic plane, it was never intended to be supersonic. It was going to fly at something like 90-95% of the speed of sound, and cut an hour or two off of intercontinental flights.
I wish they'd built it just so we could have planes that look like they belong in the 21st century at our airports.
Re:Now (Score:3, Funny)
*sigh* did you RTFA? Supersonic travel allows you to outrun the sound waves emanating from your neighbours stereo.
Re:Now, whose account? (Score:2)
Crimony!!! Would my account go for that?
Re:Now (Score:5, Funny)
I know for a fact it works on cats.
Re:Now (Score:2, Funny)
had nothing to do with the concorde's success... (Score:5, Insightful)
Re:had nothing to do with the concorde's success.. (Score:2)
Re:had nothing to do with the concorde's success.. (Score:2)
Re:had nothing to do with the concorde's success.. (Score:5, Interesting)
The concorde was a major money maker for BA, less so for Air France. The fuel costs were expensive but not unprofitably so. A standard 747 holds 300 people, most in cattle class. All seats on Concorde are first class.
The reason the plane failed economically was part due to the oil price shock hitting when Concorde entered service. A much bigger factor was Boeing lobbying to have Concorde banned from the main US airports, a piece of protectionism the US govt. went along with.
The Concorde consoirtium had the last laugh, these days it is known as Airbus and the Economist thinks it likely that Boeing will be out of the civil aviation business entirely in ten years time. In response to the US protectionism the EU underwrote development of Airbus. Boeing tried to respond with the idiotic 'fly by wire is dangerous FUD' and the rest is la historie. Boeing's current survival strategy is renting some very overpriced fuel tankers to the pentagon that meet far fewer of the original criteria set than the Airbus bid and cost about twice as much. But don't call that protectionism, its free enterprise.
Re:had nothing to do with the concorde's success.. (Score:3, Insightful)
for the sarcasm impared... (Score:2)
For what it is worth, as a former employee one of Boeing's engine suppliers I think that the american aerospace industry (well at least the aero part, maybe not the space part, but we will have to see how bush's mars thing pans out, I am sceptical) (how's that for an excesive parenthetical?) is in for very rough times soon...
Re:had nothing to do with the concorde's success.. (Score:3, Informative)
Airbus thinks that the airlines will continue to consolidate their hubs. If so, they'll ditch the aging 747 platform for A380.
Boeing thinks that airlines will add more nonstop routes between secondary cities-- e.g Detroit to Shanghai. If so, they'll probably buy more 7E7's, as
Re:had nothing to do with the concorde's success.. (Score:3, Interesting)
Re:had nothing to do with the concorde's success.. (Score:3, Informative)
Re:had nothing to do with the concorde's success.. (Score:3, Informative)
The difference is in where the burden lies. Apparently (taking the parent post at face value), in the past manufacturers had to prove to the FAA's satisfaction that a design was safe. Now, they just have to give the design to the FAA, and the assumption is that it will be certified unless the FAA proves that it is unsafe (therefore the burden of proof is on the government).
Ob
Re:had nothing to do with the concorde's success.. (Score:3, Interesting)
You may not realize this, but there are people, lots of people, who are both willing and able to pay $10,000 for a plane ticket, if only to get from London to New York in half the time. For some people (bankers, investors, musicians, models, movie stars, people of that nature), it actually makes damn good financial sense to pay that much ex
Here are the Concorde problems: (Score:3, Informative)
2. The plane's range limited itself to flying between New York City and London/Paris--and even then the plane require priority handling by air traffic control during its flight.
3. The plane's carrying capacity was too low for its size.
4
Re:Here are the Concorde problems: (Score:5, Informative)
1) The wings were virtually hand made. This was because at the time of manufacture CNC machines had not been really developed. As a consequence when the linings were put in the fuel tanks on the BA aircraft after the Paris crash, they found the shape of the fuel tanks on each aircraft were completely different. The TU144 (Concordski) had less complicated wings, due to the use of Canards on the front of the aircraft.
2) Concorde could only just make JFK from Paris. If the wind were in the wrong direction, the plane couldn't fly. The proposed (but never built) B version of Concorde could have flown Supersonic from Germany to JFK, and could have reached a number of other destinations from London.
3) The Avionics on Concorde needed to be replaced for the aircraft to continue in service past 2004. I know this as the company I work for built the engine controllers, which were the first controller to have full digital control (RB211 engines on the 747 didn't get this until the 1980's). Needless to say the work was cancelled.
4) After the Paris crash, the work carried out on the aircraft meant that the Air France Concorde could not operate fully loaded with 100 passengers. I believe as Air France could then no longer operate the aircraft economically, therefore withdrew their service. This also made the BA service unviable. Due to political reasons the aircraft were not sold to another air carrier that were prepared to continue operating the aircraft (Virgin Atlantic).
To date Concorde is one of only 2 aircraft with supercruise capability (flying above Mach 1 without afterburn); the other is the F22. It has flown more hours supersonically than all the other supersonic planes in the world.
I spoke to Sir Richard Branson (Owner of Virgin Atlantic) live on BBC TV the day before Concorde was withdrawn from service. I asked him when he expected the replacement for Concorde to enter service, and he replied "not for another 30 to 40 years". I would hope that the developments into reducing supersonic noise and jet engine fuel economy would allow the development of a large passenger jet within the next 15 to 20 years, but that depends on the airline market for such an aircraft. A small supersonic business jet capable of reaching mach 1.4 may be in service in as little as 3 to 4 years, especially as Concorde is no longer in service.
Concorde will end up in history as the aircraft equivalent of the SS Great Eastern; a large Brunel ship that was built some 50 years ahead of its time. It too was never a commercial success, and was scrapped 30 years after entering service. No ship of the size of Great Eastern was built under the SS Titanic era of the early 20th century.
SONIC BOOM (Score:2, Funny)
Re:SONIC BOOM (Score:2)
You have clearly never seen Shock Treatment [imdb.com]. Witness picture of Ruby Wax making sweet love to an elderly orangutan [shocktreat...etwork.com]. "Some people do it for the money..."
Gawd, the internet has everything...
--
Evan
Directing the sound? (Score:3, Interesting)
Re:Directing the sound? (Score:5, Informative)
Re:Directing the sound? (Score:2, Informative)
Re:Directing the sound? (Score:2)
Re:Directing the sound? (Score:2)
Nope. They though of the idea in the 70's, if I remember correctly. They simply didn't have the ability to properly model the aircrafts until the advent of extremely powerful computer aided designs which allowed modelling of the airflow both in front and hundreds of feet behind the aircraft.
I've always wondered... (Score:2)
Re:I've always wondered... (Score:5, Informative)
This is why there are two booms from each aircraft. The first one from the pressure wave preceding the plane, and the second from the posterior wave.
Re:I've always wondered... (Score:5, Informative)
The main boom is the one I was describing, and as far as I can tell, it was accurate. At least the Wikipedia [wikipedia.org] seems to agree with me:
Re:I've always wondered... (Score:2)
Re:I've always wondered... (Score:2)
Re:I've always wondered... (Score:2)
So anyway, I believe the nose of the plane creates a cone-shaped shockwave through the air at all times while it's traveling over Mach 1, and you only hear the sonic boom when you're in the hyperbolic path the cone forms when i
Re:I've always wondered... (Score:3, Informative)
When a jet flies by, you would hear two booms: one at the front when the nose pierces the air, and another at the rear when the air fills the void behind the aircraft (in theory its polarity would be opposite that of the first).
Read about it here: Doppler Shift [kettering.edu]
Finally... (Score:5, Interesting)
Not only did the Concorde jump the gun by a few decades, I think it's hindered any development into the field of Commercial Supersonic Transport by being an noisy fuel-hog... Though it was one of the most beautiful planes ever built, right up there with the SR-71...
Offtopic... (Score:3, Interesting)
Re:Offtopic... (Score:2)
Well. Unless you count the video of the mid-air collision which effectively ended the development program. *THAT* was cool... Tragic, but very, VERY cool.
disagree (Score:2)
Re:disagree (Score:2)
That's my point. It *was* too soon for a decent SST. Had it been run as a free-market expirement, it would have ended a few years after it was brought to the public. The only reason it survived as long as it did was the fairly hefty initial government subsidies.
Had the industry instead waited for the technology to mature, which it is to some degree now, it wouldn't suffer from the ne
"SONIC BOOM!" (Score:2, Interesting)
But seriously, while this could be very cool for frequent travelers, I still think that even regular airplanes are too loud. Especially if you live relatively near an airport. Are any airplane manufacturers working on quieter sub-sonic planes?
Re:"SONIC BOOM!" (Score:5, Insightful)
The short answer is "yes"
.The long answer is "yes, but it's proving to be very difficult."
It used to be that the primary cause of (commercial) jet noise was the engines. Manufacturers have managed to reduce the acoustic output from the engines (somewhat :) through engineering and operation changes (see here [technologyreview.com] for example).
Other challenges include aerodynamic noise and structure-borne noise. Aerodynamic noise reduction can hopefully be achieved through shape changes. Structure-borne noise is a little difficult because it's difficult to mitigate without adding weight to the plane.
My personal feeling is that structure-borne noise reduction can be accomplished using active-vibration reduction, but then again, I'm more of a surface-transportation noise-guy than an aero/astro noise guy.
Re:"SONIC BOOM!" (Score:2)
Thirty-some years ago, Arthur Haley (sp?) wrote "Airport". In it, one of his characters said something incredibly simple. It is, he said, simply not possible to tiptoe a quarter of a million pounds of machine anywhere.
That was when the Boeing 707 was still pretty close to the state of the art. Modern transports are anywhere from that size to three times that size, and are actually much quieter. A LOT has been learned in thirty years about building quiet
Re:"SONIC BOOM!" (Score:2)
Dhalsim, Chun Li, Blanka, Guile... so much more fun.
PopSci... (Score:5, Informative)
All Zoom, No Boom
Teaching an F-5E Tiger how to tiptoes.
There's nothing more dramatic than a supersonic jet streaking overhead; and nothing more annoying than the bone-rattling sonic boom it leaves behind. The boom really consists of two bangs caused by the N-wave in the planes wake, with rapid pressure rises corresponding to the nose and tail. Northrop-Grumman hopes that by tailoring a F-5E Tiger with a longer nose an modified tail, and tinkering wiht its body and wngs, the boom can be transformed into a smooth, inaudible hump. Engineers got the idea from research that goes back to the 1970's. Today's computers, which make it possible to model airflows up to 200 yards from a plane, were required to put the theories into practice. Tests being next august. --Written by Bill Sweetman.
I don't know exactly when it was published, but it shows that this is really no new idea. On an interesting side-note, my uncle worked for McDonald Douglas before they were bought out by Boeing, and actually was a systems engineer for the Coherent Readar systems for the F-5F. When I told him about this he thought it was one of the coolest things he'd ever heard.
~I was playing poker with tarot cards the other night. I got a full house and that same night five people died. True story.
McDonald Douglas? (Score:4, Funny)
It's not the noise (Score:3, Insightful)
Re:It's not the noise (Score:2)
Re:It's not the noise (Score:2)
Concords were only allowed to fly in certain areas because of the sound issue, so indeed the sound is a problem.
It was a problem, but is akin to worrying that your latest sports car is too noisy to carpool the neighborhood kids to school. Who gives a flying ****? You'd have to make 8 trips instead of 1 and at 12 miles per gallon fuel consumption. No, the noise was the lowest on a long list of problems.
Only a niche market wants fast. The general populace would much prefer cheap.
Re:It's not the noise (Score:2)
Do it in 3000ft over new york and youll have more glass on the street than at 9/11
Re:It's not the noise (Score:3, Insightful)
This is much better than my solution (Score:2, Funny)
This year's NAB conference had an SST group (Score:2)
Anyone know what the heck these guys were doing in there
my guess is... (Score:2, Interesting)
Of course, ya never know. I worked tradeshows for 15 years, I have seen some thoroughly weird stuff, and some incredible stuff that just disappeared, never heard of it again. O
Let's face it. (Score:4, Insightful)
Let's face it, the main reason the Concorde wasn't allowed to fly over the US is because it wasn't US made.
Re:Let's face it. (Score:5, Interesting)
But alas, no. The Concorde has a much higher 'figure of merit' (FM), and creates a much larger boom than a fighter. The size of the boom relates to the weight and length of the aircraft, and since the Concorde is much heavier than the relatively small Fighters...
The Concorde has an FM of 1.4, wheras most fighters have less than a 1... Translation: Concorde leaves a much bigger boom.
Fun SR-71 fact (Score:5, Funny)
Re:Fun SR-71 fact (Score:2)
The unexpected result was that quite a few people got on the bus and faked being injured in an attempt to have a claim.
Supercruising also important (Score:5, Informative)
Most supersonic aircraft require afterburners in order to go faster then sound, and afterburners are incredibly voracious consumers of fuel. I think that one of the other very important innovations is the "Supercruise" ability, seen on aircraft like the F-22 Raptor [lmaeronautics.com]. This allows the aircraft to maintain supersonic speed for extended periods of time in a low power setting, and this in turn is just as vital for cheap, commercially viable flights. I hope that advances in sonic boom suppression will also work well with the necessary designs for supercruising, and that we may all be able to take advantage of such flights within the next 2-3 decades. If both aren't taken into account, and designers come up with plans that make for an either-or choice, it could mean supersonic planes will still be relegated to the relatively wealthy.
Pulse detonation engine (Score:2)
Here's an article [popsci.com] on a new type of jet engine being developed, a pulse detonation engine or PDE. It promises to boost thrust considerably, while at the same time dramatically reducing fuel consumption.
It's most likely anticipation of PDE that's driving the innovation in reducing noise from supersonic flight. Supersonic flight will be commonplace when PDE gets off the ground.
Re:Pulse detonation engine (Score:2, Funny)
true but (Score:2)
So no tech breakthroughs, as supercruise technically existed in the Con
Re:the Concorde cruises at Mach 2 (Score:2)
The reheats are turned back on, by the piano switches behind the thrust leavers, for around 10 minutes once the aircraft is clear of land, to push the aircraft through Mach1 and on to Mach1.7 where they are no longer required. [concordesst.com]
The F-22 can exceed M1 withuot any afterburner use at all.
Re:Supercruising also important (Score:3, Informative)
In other words, according to the link you provided, the plane must still use afterburners to reach its supersonic cruise speed. Afterwhich, afterburners are not required to maintain the speed.
Did I misunderstand?
Blah blah blah words words words (Score:5, Funny)
Geeks like us, and researchers looking to get more grant money, have been babbling about fusion, flying cars, a return to the moon, a trip to Mars, terraforming Mars, anti-gravity devices, transporters, replicators, eternal life, brain transplantation and human cloning for-fucking-ever. YOU KNOW WHAT? I AM FUCKING SICK OF READING ABOUT SPECULATIVE FLIMFLAM. I want to read, for once, a story like:
Flying cars being sold from reputable Web site for $20,000 RIGHT NOW
Holy shit: Man lands on Mars!
Fusion reactor perfected; lauded as "great success". Test reactor already tethered to power grid generating $BIGNUM megawatts; construction on fullscale reactor underway. AND...
Silent supersonic airliner makes first of new daily Transatlantic flights wearing $MAJOR_AIRLINE colours. Book tickets at $URL.
Stop wasting my fucking time until something is actually AVAILABLE NOW. God, I'm fucking sick of reading this kind of pie-in-the-sky bullshit! It's all over SlashDot and, to a lesser extent, all over the "mainstream" news media. Fuck this shit, I don't want to hear about how "at some point in the "near" future" we "may" have such-and-such. I want a fucking link to buy one on walmart.com.
Fucking Christ, are all research organisations just like us geeks-- starting projects but never finishing them?
Oh, and you over there at moller.com [moller.com]: STOP BABBLING ABOUT YOUR GOD-DAMNED FLYING CARS [moller.com] AND START SELLING THE FUCKING THINGS ALREADY!!! YOU'RE ALREADY 10 YEARS LATE, YOU FUCKWITS! And if the FAA won't let you sell them in the US, SELL THEM ELSEWHERE. RIGHT FUCKING NOW!
Please to be modding up, sirs! (Score:2)
High. Larry. Us.
I laff.
I am damn glad... (Score:2)
Re:Blah blah blah words words words (Score:2)
I believe the headline you're looking for is:
Holy Fucking Shit: Man Lands on Goddamn Mars, Jesus Christ.
different strokes for different folks (Score:3, Insightful)
A lot of intriguing stories are for our own mental enrichment; an external reward is not necessary. They're not time wasters (in the fundamental sense) for us when
Re:different strokes for different folks (Score:2)
The need (Score:3, Insightful)
Doesn't matter in the long run... (Score:4, Interesting)
Besides, whats the best we can do commercially? Mach 2 or 3 in the 'near' term (15-30 years). Big deal. Given the cost/benifit ratio I'm going to wager that we will be doing sub-orbital before we have air-breathing mach-3 flight.
Why? The amount of development required to develop 'quiet' and 'fuel efficient' supersonic craft vs. the level of technology already in existance for boosted flight. Leave the atmosphere and sound isn't an issue, and saves a lot of fuel as well; although spending an hour weightless is bound to upset a few tummies.
Either way, I am desperate to see some faster travel. 8 hours to Chicago from London 57 years after breaking the sound barrier and 35 years after landing on the moon is a sad commentary on the human condition at present.
Re:Doesn't matter in the long run... (Score:2, Funny)
"Eat a Dramamine and shut the fuck up, pussy."
Re:Doesn't matter in the long run... (Score:2)
When the X-15 was flying NASA essentially shuttle technology 20 years before the shuttle itself. What delayed the inception was Kennedy's push in the Apollo project which was an aviation evolutionary throwback.
Re:Doesn't matter in the long run... (Score:3, Interesting)
Yes, I can certainly see how "sad [a] commentary on the human condition at present" this is, that a mere 171 years after you would have
Nosejob (Score:2, Funny)
crappy science writing (Score:2)
sonic booms are not one time events (Score:3, Informative)
Basically there would be a violent rumble on the ground over the entire length of the plane's flight corridor. The idea is to reduce or remove entirely the shockwave coming off the vehicle surfaces.
What we really need (Score:4, Interesting)
There are lots of people that want to do New York- Paris in 1 hour, but most people I know aren't in that situation.
Maybe a blimp-like plane, that could transport transatlantic freight faster than a sea ship but at similar cost, or passengers on a leisurely voyage.
Fuel savings could make up for some of the extra costs. Better efficiency might appeal to the green crowd too.
Other advantages would include less jet-lag, and hopefully a more relaxing adventure.
And another one: terrorists aren't likely to send a blimp into a building at a stealthy 100kmh
Ok, can some
Re:What we really need (Score:2)
The Big Question I Haven't Seen Answered... (Score:4, Interesting)
And in the larger sense, what is the fuel efficiency delta between the quietest plane verses the most fuel efficient design possible.
Unless that delta is quite small, I'd say it ain't going to happen.
Plane in the lower left corner (Score:4, Funny)
I could tell you, but then I'd have to kill you.
Skunkworks is working on a supersonic business jet (Score:2, Interesting)
For those that don't know, Bershire Hathaway owns Netjets, the largest purchaser of business jets.
Fluel? (Score:2)
So if reducing the sonic boom would reduced drag it already would have been discovered and implemented long ago. Those planes with less noise would probably have a baaaad fluel efficiency.
Well, maybe not
Factual error in article (Score:3, Informative)
Of course it was even less efficient than the Concorde, but it did exist
Wow. This must be embarassing.. (Score:3, Informative)
The plane in the top right is definitely an F-15 as is stated in the caption. The side-mounted air intakes are a little hard to see, but are obviously different from the bottom-mounted air intake of the F-16, however the giveaway is the tail. F-16s have a very differently shaped tail than the F-15, and it's an F-15 tail in the picture.
Re:Looking at the picture (Score:4, Informative)
Top right - F-15
Center - Modified F-5
Bottom left - Standard F-5, painted in TigerShark livery.
The F-20 [fas.org] is just slightly different frm the F-5, as evidenced by the extra bulk around the tail root.
This particular F-15B from NASA has a different nose. More pointed than a line model. That is why you were confused.
Re:Looking at the picture (Score:4, Informative)
The F-5 in the lower left is owned by the Navy. The reason that it has the Red Star painted on it is that it's an agressor plane used by the Top Gun dogfighting school.
Re:Looking at the picture (Score:2)
I thought Northrop abandoned the F-20 Tigershark?
Re:Looking at the picture (Score:3, Informative)
Air Force uses an F5 variant called the T-38. [fas.org] You see the Shuttle pilots flying these around, and they are used as the chase planes on landing.
Good aircraft. They are supersonic, nimble, stable, and are good for teaching multi-engine techniques.
Re:Looking at the picture (Score:2)
Shhhh, you aren't supposed to say anything... (Score:2)
Obviously whoever wrote the caption didn't see it, so it would only be courteous not to mention it.
that is an opfor plane (Score:4, Informative)
Re:that is an opfor plane (Score:3, Interesting)
Re:That third plane is weird (Score:2, Informative)
Re:And what about cars and buses... (Score:2)
But also, an aerodynamic shape is the antithesis of efficient storage and transport of boxes. Is the aerodynamic advantage at 60mph enough to offset the lessened cargo capacity? Doubtful, otherwise they would have done it.