Zeke
19th Jun 2001, 10:36
Time saved on major routes
Flights, Current time, Time savings
L.A.- Boston, 5 hours, 40 minutes 35 minutes
N.Y.- London, 7 hours, 50 minutes
San Francisco- Tokyo, 10 hours 45 minutes, 1 hour, 20 minutes
Singapore- London, 13 hours 40 minutes, 1 hour, 55 minutes
The proposed Boeing jet would shave time off long flights. Times are approximate.
Source: USA TODAY research
06/18/2001 - Updated 04:49 PM ET
Boeing gambles on speed with Sonic Cruiser
By Alan Levin, USA TODAY
SEATTLE — In 1958, Boeing bet its future on a sleek jet unlike anything that had come before. The 707 flew higher, faster, farther and quieter than the propeller planes of the day. Almost overnight, it catapulted Boeing to the top of the commercial aviation business.
But something unexpected happened in the decades that followed. Despite improvements that allow jets to fly farther and quieter, none but the Concorde flies much faster than 550 mph, the 707's original cruising speed.
Now Boeing is gambling it can finally build an economically viable passenger jet that can fly on the verge of the sound barrier.
Boeing
Boeing "Sonic Cruiser" may transform commercial aviation, flying just under the speed of sound.
Boeing says that its proposed "Sonic Cruiser" will fly as much as 20% faster than current models, perhaps as fast as 648 mph. The jet will be capable of flying long distances, possibly linking cities such as New York and Singapore with non-stop flight. And, more important, it won't cost airlines more to operate than today's jets, the company says.
The Concorde flies at more than twice the speed of sound, but unpleasant sonic booms, jet emissions at high altitudes and high fuel costs doomed its potential. Only two airlines fly the Concorde, and no one is building a replacement.
For the Sonic Cruiser to be able to fly just under the speed of sound, Boeing has to battle the laws of physics and economics. The jet must minimize the shock waves that other passenger jets encounter at those speeds. And its engines can't burn too much fuel.
The new jet could hardly be more different from existing large jets. Preliminary drawings show the Sonic Cruiser with huge wings that angle from the rear of the fuselage, rather than from the middle. Instead of a tail to keep it level, it will have two small wings near its nose. Passengers shouldn't feel any differences from a regular flight.
Experts say the jet could transform commercial aviation. Boeing estimates it will begin operating in six or seven years. "If the planes can really do what Boeing says they will, the major airlines will have no choice. They can buy them, or they can become a coal-hauling cargo operation," says Richard Aboulafia, aviation director for the Teal Group Corp. consultants.
Boeing officials say they will need the rest of the year to complete the design and to decide such things as how many passengers the jet will hold. They say it will probably carry about 200.
Officials at Airbus, Boeing's rival in the large jet business, call the Sonic Cruiser a ruse designed to hide Boeing's failure to develop a new jumbo jet. Airbus plans to build a jet that will carry 550.
John Leahy, Airbus' executive vice president for customer affairs, says Boeing's jet won't fly as fast or as efficiently as Boeing claims. "There is no such thing in this industry as a free lunch," he says.
High expectations for new jet
As Boeing prepared for a new round of publicity on the Sonic Cruiser at this week's Paris Air Show, USA TODAY interviewed dozens of aerodynamic experts, airline officials and sources close to Boeing to learn more about the new jet and its chances of success. According to these experts:
The speeds promised by Boeing can be attained.
In the early '70s, teams at NASA devised plans for a jet that would fly at 98% of the speed of sound. (Sound travels at 661 mph in the high altitudes where the Sonic Cruiser will fly.) Design elements were tested in flight, and models performed well in wind tunnels.
"Oh, yeah," says Richard Whitcomb, retired NASA aerodynamicist, on whether a passenger jet can fly that fast. "Easily. I did it." Indeed, though the drawings released by Boeing look vastly different from Whitcomb's models, officials say the jet will incorporate key principles that he pioneered.
The radical design presents Boeing engineers brand-new challenges.
Instead of tweaking familiar jets, engineers must wrestle with new issues. The Sonic Cruiser's design makes it inherently less stable than traditional aircraft, for example. And although the jet won't normally be flown above the speed of sound, Boeing will most likely have to demonstrate to federal regulators that it can safely fly at supersonic speeds in an emergency, such as a sudden descent.
The economics of the new jet, more than technical issues, might decide its future.
Boeing says the new jet will fly at 628 to 648 mph but will not cost airlines more to operate, as measured per seat, per mile, than current models. Even if it costs slightly more, analysts believe the benefits to passengers of saving up to two hours on long flights will far outweigh the extra cost.
If the Sonic Cruiser costs 10% to 15% more to fly, the jet will be less attractive. If costs go any higher, then the new jet could be doomed. "This has to be economically attractive," says John Roundhill, Boeing's vice president of marketing for the Sonic Cruiser.
Breaking the sound barrier
The lure of speed has long drawn aircraft manufacturers toward Mach 1 — the sound barrier. But the complex physics of flying just below the sound barrier have beaten them back.
Mach 1 is the speed at which sound waves move through the air. A jet moving through the air creates sound waves. When the jet reaches the same speed as those sounds, it throws off a shock wave. People can hear the result as a "sonic boom." The speed of sound changes with temperature. Sound travels at about 740 mph at sea level and drops to 661 mph above 36,000 feet as temperatures fall.
Up to Mach .80 (eight-tenths the speed of sound), air flows smoothly and predictably across the surfaces of an aircraft. Above Mach .80, things start to get chaotic.
As air flows over curved surfaces (such as wings and the front of the fuselage), it speeds up. As a result, even though a jet is flying at Mach .90, air may be flowing at supersonic speeds over parts of it.
When this occurs, shock waves dance about the wings and fuselage, buffeting the jet and dramatically increasing drag. Drag is the amount of resistance the air places on the jet. The effects of flying near the sound barrier were so severe in early aviation tests after World War II that some theorized the barrier could not be broken.
Since the first supersonic flight in 1947, technological advances have allowed military jets and a few civilian models to fly above Mach 1. Concorde passengers hardly notice passing the sound barrier.
But flying near the speed of sound has remained difficult. A small increase in speed near Mach 1 can cause the engines to guzzle fuel. To keep expenses down, jets mostly fly at Mach .75-.85.
After a supersonic jet program in this country failed around 1970, NASA and the aviation industry tried to make jets fly closer to Mach 1. Led by Whitcomb's discoveries in NASA's wind tunnels, the group equipped a fighter jet with a new wing and flew it just below the sound barrier in test flights. A thinner, flatter wing and strategic reshaping of the fuselage reduced shock waves and lowered drag. Several manufacturers, including Boeing, developed plans for the new jet.
But as fuel prices soared in 1973, the industry reversed course. Instead of more speed, airlines demanded jets that used less fuel. The new designs were shelved.
They weren't forgotten, however. Several of the young Boeing engineers who worked on the failed program in the '70s are now key company executives. They include Roundhill, Alan Mulally, president of the company's commercial aviation division, and Walt Gillette, the Sonic Cruiser program manager.
In an interview, Roundhill offered few specifics about the design. But he confirmed that several factors played a role in the decision to proceed with the jet.
Computers play a key role
Powerful new computers make designing jets easier. Supercomputers can calculate air flows and suggest optimum shapes of a jet.
New composite materials made of graphite weigh 20% less than metal alloys and can make aircraft much lighter. Roundhill said that Boeing might build the wings and fuselage with composites. And computers imbedded in cockpits can make unruly jets easier to fly.
Roundhill also confirmed reports that an unnamed engineer had come up with a breakthrough that helped make the jet possible. He wouldn't identify the breakthrough or even the engineer.
One thing that clearly set the drawings of the Sonic Cruiser apart from current jets was the decision to place the jet's wings at the rear of the fuselage. Aerodynamic experts say this solves a big problem in the earlier designs for a faster jet.
To minimize sonic shock waves, a jet's fuselage must be narrower where the wings attach. On a traditional jet, this would require a narrow middle section of the fuselage. Manufacturers feared passengers would feel awkward boarding such a jet. It also costs more to build.
On the Sonic Cruiser, the fuselage will be narrowed at the rear because the wings attach there. As a result, the fuselage is closer in shape to a traditional jet's.
On the same day last March that Boeing unveiled the Sonic Cruiser, company officials also said they would not build a jumbo jet to succeed the 747. For the first time, Boeing conceded the market for the world's largest jet to a competitor. Airbus had recently announced it would build the A380, a jet that will carry 550 passengers. It believes airlines will need very large jets to reduce the number of flights in and out of overburdened hub airports.
Design challenges
Boeing has a different philosophy. It thinks airlines will bypass those hubs with smaller jets flying non-stop to distant destinations. In other words, airlines want a jet like the Sonic Cruiser that can fly faster and farther than today's jets. Continental Airlines CEO Gordon Bethune, a former Boeing executive, agrees. The other airlines "who are late with the (Sonic Cruiser) are going to be very much at a disadvantage against me," he says.
Several aerodynamic experts are more cautious. They don't doubt that it can fly, only that its unusual configuration could make it too costly and awkward to build.
"There are some definite design challenges there," says Peter Coen, an aerospace engineer at NASA Langley Research Center. "But I think they could be met."
Jerry Grey, a visiting professor at Princeton University and nationally known aerodynamics authority, says, "If I had to guess, I would have to say that it will probably never be developed and never fly."
Boeing has announced new aircraft before, only to drop them in the face of airline indifference. It could happen with the Sonic Cruiser, Roundhill concedes. But he doesn't think so. "We wouldn't even be focusing on this if we didn't believe it would be economically viable," he says.
Flights, Current time, Time savings
L.A.- Boston, 5 hours, 40 minutes 35 minutes
N.Y.- London, 7 hours, 50 minutes
San Francisco- Tokyo, 10 hours 45 minutes, 1 hour, 20 minutes
Singapore- London, 13 hours 40 minutes, 1 hour, 55 minutes
The proposed Boeing jet would shave time off long flights. Times are approximate.
Source: USA TODAY research
06/18/2001 - Updated 04:49 PM ET
Boeing gambles on speed with Sonic Cruiser
By Alan Levin, USA TODAY
SEATTLE — In 1958, Boeing bet its future on a sleek jet unlike anything that had come before. The 707 flew higher, faster, farther and quieter than the propeller planes of the day. Almost overnight, it catapulted Boeing to the top of the commercial aviation business.
But something unexpected happened in the decades that followed. Despite improvements that allow jets to fly farther and quieter, none but the Concorde flies much faster than 550 mph, the 707's original cruising speed.
Now Boeing is gambling it can finally build an economically viable passenger jet that can fly on the verge of the sound barrier.
Boeing
Boeing "Sonic Cruiser" may transform commercial aviation, flying just under the speed of sound.
Boeing says that its proposed "Sonic Cruiser" will fly as much as 20% faster than current models, perhaps as fast as 648 mph. The jet will be capable of flying long distances, possibly linking cities such as New York and Singapore with non-stop flight. And, more important, it won't cost airlines more to operate than today's jets, the company says.
The Concorde flies at more than twice the speed of sound, but unpleasant sonic booms, jet emissions at high altitudes and high fuel costs doomed its potential. Only two airlines fly the Concorde, and no one is building a replacement.
For the Sonic Cruiser to be able to fly just under the speed of sound, Boeing has to battle the laws of physics and economics. The jet must minimize the shock waves that other passenger jets encounter at those speeds. And its engines can't burn too much fuel.
The new jet could hardly be more different from existing large jets. Preliminary drawings show the Sonic Cruiser with huge wings that angle from the rear of the fuselage, rather than from the middle. Instead of a tail to keep it level, it will have two small wings near its nose. Passengers shouldn't feel any differences from a regular flight.
Experts say the jet could transform commercial aviation. Boeing estimates it will begin operating in six or seven years. "If the planes can really do what Boeing says they will, the major airlines will have no choice. They can buy them, or they can become a coal-hauling cargo operation," says Richard Aboulafia, aviation director for the Teal Group Corp. consultants.
Boeing officials say they will need the rest of the year to complete the design and to decide such things as how many passengers the jet will hold. They say it will probably carry about 200.
Officials at Airbus, Boeing's rival in the large jet business, call the Sonic Cruiser a ruse designed to hide Boeing's failure to develop a new jumbo jet. Airbus plans to build a jet that will carry 550.
John Leahy, Airbus' executive vice president for customer affairs, says Boeing's jet won't fly as fast or as efficiently as Boeing claims. "There is no such thing in this industry as a free lunch," he says.
High expectations for new jet
As Boeing prepared for a new round of publicity on the Sonic Cruiser at this week's Paris Air Show, USA TODAY interviewed dozens of aerodynamic experts, airline officials and sources close to Boeing to learn more about the new jet and its chances of success. According to these experts:
The speeds promised by Boeing can be attained.
In the early '70s, teams at NASA devised plans for a jet that would fly at 98% of the speed of sound. (Sound travels at 661 mph in the high altitudes where the Sonic Cruiser will fly.) Design elements were tested in flight, and models performed well in wind tunnels.
"Oh, yeah," says Richard Whitcomb, retired NASA aerodynamicist, on whether a passenger jet can fly that fast. "Easily. I did it." Indeed, though the drawings released by Boeing look vastly different from Whitcomb's models, officials say the jet will incorporate key principles that he pioneered.
The radical design presents Boeing engineers brand-new challenges.
Instead of tweaking familiar jets, engineers must wrestle with new issues. The Sonic Cruiser's design makes it inherently less stable than traditional aircraft, for example. And although the jet won't normally be flown above the speed of sound, Boeing will most likely have to demonstrate to federal regulators that it can safely fly at supersonic speeds in an emergency, such as a sudden descent.
The economics of the new jet, more than technical issues, might decide its future.
Boeing says the new jet will fly at 628 to 648 mph but will not cost airlines more to operate, as measured per seat, per mile, than current models. Even if it costs slightly more, analysts believe the benefits to passengers of saving up to two hours on long flights will far outweigh the extra cost.
If the Sonic Cruiser costs 10% to 15% more to fly, the jet will be less attractive. If costs go any higher, then the new jet could be doomed. "This has to be economically attractive," says John Roundhill, Boeing's vice president of marketing for the Sonic Cruiser.
Breaking the sound barrier
The lure of speed has long drawn aircraft manufacturers toward Mach 1 — the sound barrier. But the complex physics of flying just below the sound barrier have beaten them back.
Mach 1 is the speed at which sound waves move through the air. A jet moving through the air creates sound waves. When the jet reaches the same speed as those sounds, it throws off a shock wave. People can hear the result as a "sonic boom." The speed of sound changes with temperature. Sound travels at about 740 mph at sea level and drops to 661 mph above 36,000 feet as temperatures fall.
Up to Mach .80 (eight-tenths the speed of sound), air flows smoothly and predictably across the surfaces of an aircraft. Above Mach .80, things start to get chaotic.
As air flows over curved surfaces (such as wings and the front of the fuselage), it speeds up. As a result, even though a jet is flying at Mach .90, air may be flowing at supersonic speeds over parts of it.
When this occurs, shock waves dance about the wings and fuselage, buffeting the jet and dramatically increasing drag. Drag is the amount of resistance the air places on the jet. The effects of flying near the sound barrier were so severe in early aviation tests after World War II that some theorized the barrier could not be broken.
Since the first supersonic flight in 1947, technological advances have allowed military jets and a few civilian models to fly above Mach 1. Concorde passengers hardly notice passing the sound barrier.
But flying near the speed of sound has remained difficult. A small increase in speed near Mach 1 can cause the engines to guzzle fuel. To keep expenses down, jets mostly fly at Mach .75-.85.
After a supersonic jet program in this country failed around 1970, NASA and the aviation industry tried to make jets fly closer to Mach 1. Led by Whitcomb's discoveries in NASA's wind tunnels, the group equipped a fighter jet with a new wing and flew it just below the sound barrier in test flights. A thinner, flatter wing and strategic reshaping of the fuselage reduced shock waves and lowered drag. Several manufacturers, including Boeing, developed plans for the new jet.
But as fuel prices soared in 1973, the industry reversed course. Instead of more speed, airlines demanded jets that used less fuel. The new designs were shelved.
They weren't forgotten, however. Several of the young Boeing engineers who worked on the failed program in the '70s are now key company executives. They include Roundhill, Alan Mulally, president of the company's commercial aviation division, and Walt Gillette, the Sonic Cruiser program manager.
In an interview, Roundhill offered few specifics about the design. But he confirmed that several factors played a role in the decision to proceed with the jet.
Computers play a key role
Powerful new computers make designing jets easier. Supercomputers can calculate air flows and suggest optimum shapes of a jet.
New composite materials made of graphite weigh 20% less than metal alloys and can make aircraft much lighter. Roundhill said that Boeing might build the wings and fuselage with composites. And computers imbedded in cockpits can make unruly jets easier to fly.
Roundhill also confirmed reports that an unnamed engineer had come up with a breakthrough that helped make the jet possible. He wouldn't identify the breakthrough or even the engineer.
One thing that clearly set the drawings of the Sonic Cruiser apart from current jets was the decision to place the jet's wings at the rear of the fuselage. Aerodynamic experts say this solves a big problem in the earlier designs for a faster jet.
To minimize sonic shock waves, a jet's fuselage must be narrower where the wings attach. On a traditional jet, this would require a narrow middle section of the fuselage. Manufacturers feared passengers would feel awkward boarding such a jet. It also costs more to build.
On the Sonic Cruiser, the fuselage will be narrowed at the rear because the wings attach there. As a result, the fuselage is closer in shape to a traditional jet's.
On the same day last March that Boeing unveiled the Sonic Cruiser, company officials also said they would not build a jumbo jet to succeed the 747. For the first time, Boeing conceded the market for the world's largest jet to a competitor. Airbus had recently announced it would build the A380, a jet that will carry 550 passengers. It believes airlines will need very large jets to reduce the number of flights in and out of overburdened hub airports.
Design challenges
Boeing has a different philosophy. It thinks airlines will bypass those hubs with smaller jets flying non-stop to distant destinations. In other words, airlines want a jet like the Sonic Cruiser that can fly faster and farther than today's jets. Continental Airlines CEO Gordon Bethune, a former Boeing executive, agrees. The other airlines "who are late with the (Sonic Cruiser) are going to be very much at a disadvantage against me," he says.
Several aerodynamic experts are more cautious. They don't doubt that it can fly, only that its unusual configuration could make it too costly and awkward to build.
"There are some definite design challenges there," says Peter Coen, an aerospace engineer at NASA Langley Research Center. "But I think they could be met."
Jerry Grey, a visiting professor at Princeton University and nationally known aerodynamics authority, says, "If I had to guess, I would have to say that it will probably never be developed and never fly."
Boeing has announced new aircraft before, only to drop them in the face of airline indifference. It could happen with the Sonic Cruiser, Roundhill concedes. But he doesn't think so. "We wouldn't even be focusing on this if we didn't believe it would be economically viable," he says.