Friday, July 21, 2006
787 - Another View
The 787 Dreamliner was launched with the promise of 20% better fuel efficiency per passenger mile. Most of the world believes the gains will come from Boeing's extensive use of composite materials for the airplane. Wrong!
In the December 6, 2004 issue of Aviation Week, p.62, Walter B. Gillette, V.P. 787 Engineering, was quoted as follows:
The 787 will have 20% better fuel efficiency.
8% from the more efficient engines
3% from improved aerodynamics
3% from more efficient systems
3% from weight savings using composite materials
3% from the synergy of the last three items
Composites bring to the table a small gain (3% plus the synergy) and 90% of the risk due to the unprecedented size and scope of composite use.
For over 40 years, composite materials have held the promise of revolutionizing aircraft construction. The revolution has yet to happen and I don't expect the Dreamliner to advance the notion. In fact, the results for airplanes larger than sailplanes have been less than stellar. Based on this shaky foundation, Boeing management concluded they can build an all composite airliner that will set new standards of efficiencies and economy for the airline industry.
This blog will examine that foundation.
Raytheon Aircraft - Wichita (formerly Beech Aircraft) has more experience building large composite aircraft structures than anyone else in the world. Both their recently developed Premier and Horizon business jets have composite fuselage structure. Both airplanes missed their empty weight targets...neither is any lighter, nor less expensive than a comparable sheet metal airplane.
In the early development phase of the Dreamliner, Boeing-Wichita (now Spirit) did extensive development work at Beech. Boeing-Wichita contracted with Beech to use their $5 million Cincinnati Milicron Viper automated graphite tape laying machine and the large autoclave Beech installed to support the Starship. In addition, Boeing engineers had free access to Beech engineers for technical support.
I often wonder if the Beech engineers informed Boeing of this little known fact: Of the 50 Starships built, the fuselage of the first was an inch longer than the last. The composite fuselage mold shrank 1/50th of an inch each time it went through the thermal cycle in the autoclave. Had this rate continued, the 1,000th Starship would have been 20 inches shorter than the first.
Realistically, the shrinkage would probably stabilize at some point but this illustrates the type of unexpected problems that can surface when you break new ground with unproven technology or scale up to unprecedented levels. You never know what surprises might surface...and unknowns are part of the risk factor.
Tooling has already been an issue for the 787. Out of the first eight barrel sections that make up a single fuselage, one failed due to air bubbles in the layup. The cause was traced to a composite layup mandrel. Tooling made out of composites have a lot of drawbacks. Durability is one, rigidity another. Especially when heated in autoclaves, they have a tendency to move around. And when you are dealing with large structures, a little variability in the process or materials can make it difficult to control expansion and shrinkage.
Failure of one barrel section is not a big deal; even more curious though is the report that Boeing is not happy with Spirit's nose section. Actually is was not a complete nose section but rather slightly more than half the length. Internally, Spirit claims they are quite happy with the way the partial nose section turned out.
The wing may prove to be an even greater challenge. The 2.5% empty weight gain Boeing is admitting to, has been attributed to the wing section. The composite 787 wing is being built by the Japanese who have experience in composite wings. In 1995, the JDA (Japanese Defense Agency) ordered 130 F-16's to be built in Japan with composite wings and called the F-2. By the time 75 were built, the price had escalated from U$D 73 million to U$D 109 million.
JDA officials have also acknowledged that the F-2 composite wing experienced cracking at high energy loads, but details have been hidden. Another confidence builder for Boeing!
Then there is the issue of costs. Material costs for composites run $25 per pound...aircraft aluminum about $4 to $5 per pound. Aluminum scrap from the manufacturing process can be resold for about $ .75 per pound. Scrap from composite manufacturing if in a solid state goes to a landfill...resins and solvents are hazardous materials and disposed of accordingly.
Resins are petroleum based and currently experiencing sharp price increases. Titanium is the metal most compatible with graphite...787 usage will be quite high...supply is also short causing severe shortages and price increases. Aluminum has not escaped the trend but its price increase is not as steep as for titanium, graphite and resins.
Why build composite airplanes? Beech started down the composite road with the Starship. Their archrival Cessna had a commanding lead in sheet metal business jets (which continues to this day). Beech management hoped to leapfrog Cessna with technology.
When management elected to proceed with the Starship program, several of Beech's best and most experienced engineers tried to tell management the company was making a mistake pursuing the plastic airplane. The dissenting engineers were told to get with the program or get out. Many left!
While the Starship was under development, Raytheon (not exactly a backwater company) bought Beech thinking they were buying into the future of aviation via the composite technology. The Starship came out heavy. The initial empty weight target was 7,793 lbs ...actual empty weight was 10,085 lbs, nearly one-third heavier. Performance suffered, sales dried up. In the end, Raytheon bought back those few in service and paid to have them incinerated. Their write-off, nearly a billion dollars. Today, Raytheon would like nothing better than to find a buyer for Beech.
It is an old adage, those who ignore history and destined to repeat it.
Beech management wanted to leapfrog Cessna with technology. Raytheon took the hit.
Airbus management wanted to dethrone Boeing as the Heavyweight Champ...the 380 by a knockout over the 747. Problems with the 380 are well known...the airplane may never turn a profit. If the truth be known, Airbus probably wishes it had never built the 380.
The decision makers at Boeing wanted an airplane that would be so efficient, it would dethrone Airbus as the sales volume leader. They believed a plastic airplane would do the trick because everybody knows that composites are lighter than aluminum.
This competitive pressure at these three companies caused each to reach too far.
By the time the 787 enters service, I predict Boeing management will rue the day they decided to make the 787 out of composites. My guess is that in the coming months, there will be more and more reports of weight problems (perhaps Boeing engineers should keep the phone number for Jenny Craig handy). As more and more of the prototype comes together, expect more discussions on cost overruns.
It would be interesting to learn about Boeing's contractual obligations to both the customers and suppliers.
Do the airlines have fixed prices with an escalator for increases in material prices?
Do the Boeing suppliers have fixed prices plus a material escalator?
What happens when Mitsubishi determines it will require twice the man-hours to build a wing as what they estimated during the bid process?
Who will pick up the slack when they learn capital expenditures will far exceed the original estimates? As quoted in Aviation Week, July 3, 2006, "Boeing doesn't know how much investment is being made in the supply chain." That begs the question, does Boeing and the suppliers have a good handle on what it will cost to produce the airplane?
Early on, Boeing made statements to the effect, the biggest benefit in going the composite route was to reduce assembly time in Seattle. They did not mention the hours the suppliers were investing in the manufacture of the sub-assemblies.
There is the issue of technology transfer that should be of concern to Boeing shareholders. The 787 wing contracts went to Japan because All Nippon Airways was the launch customer with an order of 50 Dreamliners. While this may have been an expedient or even a necessary thing to do, the problem is, Boeing will be giving away their wing technology which is the magic in the magician's hat in terms of aircraft technology.
Ramblings:
The 787 development program is off the starting grid and rounding the first turn. The finish line is a long way off. Boeing is already admitting to a 2.5% empty weight growth. The small percentage does not sound like much but it is 6,000+ pounds.
A 20% gain in efficiency is huge, comparable to the shift from turbojet engines to turbofans. We are 50 years plus into the commercial jet age; it is a very mature technology. The character of mature technology is that small gains come at a high price.
Had Boeing elected to build the 787 out of aluminum:
- they would be claiming about 15-17% better fuel efficiency.
- they could use their existing (and proven) supplier base.
- their order book would be just as fat.
- there would be fewer ulcers in Seattle.
- this blog would not exist.
I have been involved with the aviation industry for 44 years and have seen a lot of programs succeed and a few fail. Early on, there is optimism for every new program. Some reach a point and say oops! Kind of like the guy who jumps off the observation deck at the Empire State Building. Every floor he passes, he yells in the window, "so far, so good."
Lastly, Boeing management promised us the 787 would have mood lighting, can't wait to see it!
In the December 6, 2004 issue of Aviation Week, p.62, Walter B. Gillette, V.P. 787 Engineering, was quoted as follows:
The 787 will have 20% better fuel efficiency.
8% from the more efficient engines
3% from improved aerodynamics
3% from more efficient systems
3% from weight savings using composite materials
3% from the synergy of the last three items
Composites bring to the table a small gain (3% plus the synergy) and 90% of the risk due to the unprecedented size and scope of composite use.
For over 40 years, composite materials have held the promise of revolutionizing aircraft construction. The revolution has yet to happen and I don't expect the Dreamliner to advance the notion. In fact, the results for airplanes larger than sailplanes have been less than stellar. Based on this shaky foundation, Boeing management concluded they can build an all composite airliner that will set new standards of efficiencies and economy for the airline industry.
This blog will examine that foundation.
Raytheon Aircraft - Wichita (formerly Beech Aircraft) has more experience building large composite aircraft structures than anyone else in the world. Both their recently developed Premier and Horizon business jets have composite fuselage structure. Both airplanes missed their empty weight targets...neither is any lighter, nor less expensive than a comparable sheet metal airplane.
In the early development phase of the Dreamliner, Boeing-Wichita (now Spirit) did extensive development work at Beech. Boeing-Wichita contracted with Beech to use their $5 million Cincinnati Milicron Viper automated graphite tape laying machine and the large autoclave Beech installed to support the Starship. In addition, Boeing engineers had free access to Beech engineers for technical support.
I often wonder if the Beech engineers informed Boeing of this little known fact: Of the 50 Starships built, the fuselage of the first was an inch longer than the last. The composite fuselage mold shrank 1/50th of an inch each time it went through the thermal cycle in the autoclave. Had this rate continued, the 1,000th Starship would have been 20 inches shorter than the first.
Realistically, the shrinkage would probably stabilize at some point but this illustrates the type of unexpected problems that can surface when you break new ground with unproven technology or scale up to unprecedented levels. You never know what surprises might surface...and unknowns are part of the risk factor.
Tooling has already been an issue for the 787. Out of the first eight barrel sections that make up a single fuselage, one failed due to air bubbles in the layup. The cause was traced to a composite layup mandrel. Tooling made out of composites have a lot of drawbacks. Durability is one, rigidity another. Especially when heated in autoclaves, they have a tendency to move around. And when you are dealing with large structures, a little variability in the process or materials can make it difficult to control expansion and shrinkage.
Failure of one barrel section is not a big deal; even more curious though is the report that Boeing is not happy with Spirit's nose section. Actually is was not a complete nose section but rather slightly more than half the length. Internally, Spirit claims they are quite happy with the way the partial nose section turned out.
The wing may prove to be an even greater challenge. The 2.5% empty weight gain Boeing is admitting to, has been attributed to the wing section. The composite 787 wing is being built by the Japanese who have experience in composite wings. In 1995, the JDA (Japanese Defense Agency) ordered 130 F-16's to be built in Japan with composite wings and called the F-2. By the time 75 were built, the price had escalated from U$D 73 million to U$D 109 million.
JDA officials have also acknowledged that the F-2 composite wing experienced cracking at high energy loads, but details have been hidden. Another confidence builder for Boeing!
Then there is the issue of costs. Material costs for composites run $25 per pound...aircraft aluminum about $4 to $5 per pound. Aluminum scrap from the manufacturing process can be resold for about $ .75 per pound. Scrap from composite manufacturing if in a solid state goes to a landfill...resins and solvents are hazardous materials and disposed of accordingly.
Resins are petroleum based and currently experiencing sharp price increases. Titanium is the metal most compatible with graphite...787 usage will be quite high...supply is also short causing severe shortages and price increases. Aluminum has not escaped the trend but its price increase is not as steep as for titanium, graphite and resins.
Why build composite airplanes? Beech started down the composite road with the Starship. Their archrival Cessna had a commanding lead in sheet metal business jets (which continues to this day). Beech management hoped to leapfrog Cessna with technology.
When management elected to proceed with the Starship program, several of Beech's best and most experienced engineers tried to tell management the company was making a mistake pursuing the plastic airplane. The dissenting engineers were told to get with the program or get out. Many left!
While the Starship was under development, Raytheon (not exactly a backwater company) bought Beech thinking they were buying into the future of aviation via the composite technology. The Starship came out heavy. The initial empty weight target was 7,793 lbs ...actual empty weight was 10,085 lbs, nearly one-third heavier. Performance suffered, sales dried up. In the end, Raytheon bought back those few in service and paid to have them incinerated. Their write-off, nearly a billion dollars. Today, Raytheon would like nothing better than to find a buyer for Beech.
It is an old adage, those who ignore history and destined to repeat it.
Beech management wanted to leapfrog Cessna with technology. Raytheon took the hit.
Airbus management wanted to dethrone Boeing as the Heavyweight Champ...the 380 by a knockout over the 747. Problems with the 380 are well known...the airplane may never turn a profit. If the truth be known, Airbus probably wishes it had never built the 380.
The decision makers at Boeing wanted an airplane that would be so efficient, it would dethrone Airbus as the sales volume leader. They believed a plastic airplane would do the trick because everybody knows that composites are lighter than aluminum.
This competitive pressure at these three companies caused each to reach too far.
By the time the 787 enters service, I predict Boeing management will rue the day they decided to make the 787 out of composites. My guess is that in the coming months, there will be more and more reports of weight problems (perhaps Boeing engineers should keep the phone number for Jenny Craig handy). As more and more of the prototype comes together, expect more discussions on cost overruns.
It would be interesting to learn about Boeing's contractual obligations to both the customers and suppliers.
Do the airlines have fixed prices with an escalator for increases in material prices?
Do the Boeing suppliers have fixed prices plus a material escalator?
What happens when Mitsubishi determines it will require twice the man-hours to build a wing as what they estimated during the bid process?
Who will pick up the slack when they learn capital expenditures will far exceed the original estimates? As quoted in Aviation Week, July 3, 2006, "Boeing doesn't know how much investment is being made in the supply chain." That begs the question, does Boeing and the suppliers have a good handle on what it will cost to produce the airplane?
Early on, Boeing made statements to the effect, the biggest benefit in going the composite route was to reduce assembly time in Seattle. They did not mention the hours the suppliers were investing in the manufacture of the sub-assemblies.
There is the issue of technology transfer that should be of concern to Boeing shareholders. The 787 wing contracts went to Japan because All Nippon Airways was the launch customer with an order of 50 Dreamliners. While this may have been an expedient or even a necessary thing to do, the problem is, Boeing will be giving away their wing technology which is the magic in the magician's hat in terms of aircraft technology.
Ramblings:
The 787 development program is off the starting grid and rounding the first turn. The finish line is a long way off. Boeing is already admitting to a 2.5% empty weight growth. The small percentage does not sound like much but it is 6,000+ pounds.
A 20% gain in efficiency is huge, comparable to the shift from turbojet engines to turbofans. We are 50 years plus into the commercial jet age; it is a very mature technology. The character of mature technology is that small gains come at a high price.
Had Boeing elected to build the 787 out of aluminum:
- they would be claiming about 15-17% better fuel efficiency.
- they could use their existing (and proven) supplier base.
- their order book would be just as fat.
- there would be fewer ulcers in Seattle.
- this blog would not exist.
I have been involved with the aviation industry for 44 years and have seen a lot of programs succeed and a few fail. Early on, there is optimism for every new program. Some reach a point and say oops! Kind of like the guy who jumps off the observation deck at the Empire State Building. Every floor he passes, he yells in the window, "so far, so good."
Lastly, Boeing management promised us the 787 would have mood lighting, can't wait to see it!
# posted by Stan Blankenship : 6:27 PM
Comments:
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I've been involved in composites research in the past and fairly recent past. Composites have never achieved the potential that everyone said so. Boeing isn't the first to prove that with an inappropriate design. Beech did that with the Starbarge and if you listen to the people involved at the time they will point out that a lot of the extra weight is due to the FAA forcing unreasonable requirements on them because they were scared of the technology. But it seems pretty sketchy. It may be that composites just aren't as effective at minimizing weight when the design addresses everything it has to.
A correction to your history.
Raytheon bought Beech about 1980 and in 1982 brought in Linden Blue to run the company and Burt Rutan to design the Starship. Beech was the victim. Raytheon was the perpetrator.
Raytheon bought Beech about 1980 and in 1982 brought in Linden Blue to run the company and Burt Rutan to design the Starship. Beech was the victim. Raytheon was the perpetrator.
griper,
Well said!
bern,
Thanks for the correction. I do not question your dates but would like to get more clarification from a retired Beech Exec before doing a rewrite on that secton.
Linden arrived at Beech after the collapse of the Learfan program and brought some of the Reno engineers with him.
Well said!
bern,
Thanks for the correction. I do not question your dates but would like to get more clarification from a retired Beech Exec before doing a rewrite on that secton.
Linden arrived at Beech after the collapse of the Learfan program and brought some of the Reno engineers with him.
bern,
There is an 8-page write up on Starship history written by Max Bleck, former Beech President and CEO.
He states development on the King Air replacement started in 1979.
It is not clear how far along the design was at the time of the Raytheon acquisition in 1982.
Re-reading the original blog, I still think it captures the essence of Raytheon's expectations.
See http://www.bobscherer.com/Files/Starship%20History.pdf
There is an 8-page write up on Starship history written by Max Bleck, former Beech President and CEO.
He states development on the King Air replacement started in 1979.
It is not clear how far along the design was at the time of the Raytheon acquisition in 1982.
Re-reading the original blog, I still think it captures the essence of Raytheon's expectations.
See http://www.bobscherer.com/Files/Starship%20History.pdf
Stan,
I am with you. Where are they now in the development of this "787" project? Also, what are the new cost projections (updated?)...
Justin (Cessna Dude) Rankin
I am with you. Where are they now in the development of this "787" project? Also, what are the new cost projections (updated?)...
Justin (Cessna Dude) Rankin
Healthy skepticism is never a bad thing, and history is replete with examples of skepticism having a positive influence on the course of technological progress. Thank God though, that the prophets of progress and evolution continue to keep us reaching ever higher for improvements, even revolutionary advances such as the high bypass turbofan engine mentioned in this blog.
My mind is constantly confounded when I ask why we ever thought to build airplanes from carbon fiber and resin systems (plastic to some), the challenges are so daunting. Nevertheless, my money is on progress away from metallic airframes, and I'm willing to bet my retirement that twenty years from today few, if any, large commercial or military airframes will be built from aluminum. Those airframes will be made instead from carbon fiber/resin laminates in addition to other composite materials whose faces have yet to emerge from the wombs of discovery.
The early large composite aircraft will be disappointing in many respects, but I suggest that the 380 and the 787 will indeed be built. If they aren’t constructed in large numbers they will nonetheless be among the first in long lines of successful composite large aircraft. Those who don’t believe it probably didn’t think aviation fuel would ever reach $3.50 per gallon, and they probably don’t believe it will ever reach $10 or $12 per gallon. I do, and so do those who control the tens of billions of dollars and euros that are being invested today in the technology of tomorrow.
Those who don’t wish to build them can move aside!
My mind is constantly confounded when I ask why we ever thought to build airplanes from carbon fiber and resin systems (plastic to some), the challenges are so daunting. Nevertheless, my money is on progress away from metallic airframes, and I'm willing to bet my retirement that twenty years from today few, if any, large commercial or military airframes will be built from aluminum. Those airframes will be made instead from carbon fiber/resin laminates in addition to other composite materials whose faces have yet to emerge from the wombs of discovery.
The early large composite aircraft will be disappointing in many respects, but I suggest that the 380 and the 787 will indeed be built. If they aren’t constructed in large numbers they will nonetheless be among the first in long lines of successful composite large aircraft. Those who don’t believe it probably didn’t think aviation fuel would ever reach $3.50 per gallon, and they probably don’t believe it will ever reach $10 or $12 per gallon. I do, and so do those who control the tens of billions of dollars and euros that are being invested today in the technology of tomorrow.
Those who don’t wish to build them can move aside!
Stan, great blog! I found it really interesting to read the observations of someone with some real experience in aircraft development. But why have you stopped after one post?! I would be interested to hear your assessment of the recent progress of the 787 and whether they will indeed deliver on time and to spec.
Phil
Phil
The revolution of composites in aerospace is arriving step by step. In hindsight the Beech Starship is an example of a design that screwed itself into a bad corner. Boeing and Airbus have had relative success with composite vertical and horiz. stabilizers. The AV-8 Harrier has a composite wing and seems to be doing ok.
Starship
Max T/O Weight: 14,900 lbs
Basic Empty Weight: 10,120 lbs
Useful Load: 4890 lbs (48% BEW)
Two of three spars had to take limit load. Complex flight controls. Tons (literally) of 'bells and whistles'.
Consider the opposite extreme in use of composites, the Global Flyer.
Global Flyer
Gross Weight: 22,000 lbs
Empty Weight: 3,350 lbs
Useful Load: 18,650 lbs (557% EW)
Razor thin margin of safety.
Minimal systems and controls.
Steve Fossett personally bought the risk and won.
Practical solutions are somewhere between.
Composites have advantages and disadvantages. To achieve performance better than metal you have to take on the full responsibility. You have to write your own page of MIL-HDBK-5. Establish your own process to actually do what your material spec says. Solve for the stress and strain to let the composite structure take the load efficiently. Did the Starship design do this?
Alcola sells you QQ-A-250 and you know that is what you get. Beat it into shape and pound it together.
When you cook up your own resin fabric you are responsible for the material too. This adds a whole new degree of complexity to the problem.
The 787 has efficient closed section longerons in the fuselage and wing. With almost no bleed air ducts they do not need to poke as many holes in the structure. The shell can be laid up in continuously varying thickness. I would like to see how they tie together the heavy structure near the aft fuselage to rear spar. If you can solve the structural design at the highest loaded fuselage to rear spar clean and simple (like the 777) then you have it all.
We are approaching the threshold of launching practical composite airframes and I believe Boeing is about to do it.
James
Starship
Max T/O Weight: 14,900 lbs
Basic Empty Weight: 10,120 lbs
Useful Load: 4890 lbs (48% BEW)
Two of three spars had to take limit load. Complex flight controls. Tons (literally) of 'bells and whistles'.
Consider the opposite extreme in use of composites, the Global Flyer.
Global Flyer
Gross Weight: 22,000 lbs
Empty Weight: 3,350 lbs
Useful Load: 18,650 lbs (557% EW)
Razor thin margin of safety.
Minimal systems and controls.
Steve Fossett personally bought the risk and won.
Practical solutions are somewhere between.
Composites have advantages and disadvantages. To achieve performance better than metal you have to take on the full responsibility. You have to write your own page of MIL-HDBK-5. Establish your own process to actually do what your material spec says. Solve for the stress and strain to let the composite structure take the load efficiently. Did the Starship design do this?
Alcola sells you QQ-A-250 and you know that is what you get. Beat it into shape and pound it together.
When you cook up your own resin fabric you are responsible for the material too. This adds a whole new degree of complexity to the problem.
The 787 has efficient closed section longerons in the fuselage and wing. With almost no bleed air ducts they do not need to poke as many holes in the structure. The shell can be laid up in continuously varying thickness. I would like to see how they tie together the heavy structure near the aft fuselage to rear spar. If you can solve the structural design at the highest loaded fuselage to rear spar clean and simple (like the 777) then you have it all.
We are approaching the threshold of launching practical composite airframes and I believe Boeing is about to do it.
James
Linden BTW is back with a composite design that is purported to be a leap in composite design and manufacturing processes.
Their efficiency gains are well over 50% and the performance characteristics of those planes are simply stunning...
What do you guys think?
http://www.spectrum.aero
Their efficiency gains are well over 50% and the performance characteristics of those planes are simply stunning...
What do you guys think?
http://www.spectrum.aero
The success of the 787 project may boil down to superb process control and we all know how cruel those lessons can be!
It seems that the FAA is concerned about the 787's computer networks and whether the flight deck is vulnerable to attack from the passenger compartment.
FAA Cautions on hacking the 787
"Because of this new passenger connectivity, the proposed data network design and integration may result in security vulnerabilities from intentional or unintentional corruption of data and systems critical to the safety and maintenance of the airplane. The existing regulations and guidance material did not anticipate this type of system architecture or electronic access to aircraft systems that provide flight critical functions."
Boeing said it's aware of the issue and has designed a solution it will test shortly.
FAA Cautions on hacking the 787
"Because of this new passenger connectivity, the proposed data network design and integration may result in security vulnerabilities from intentional or unintentional corruption of data and systems critical to the safety and maintenance of the airplane. The existing regulations and guidance material did not anticipate this type of system architecture or electronic access to aircraft systems that provide flight critical functions."
Boeing said it's aware of the issue and has designed a solution it will test shortly.
Stan,
Excellent blog... I want to hear more. Having been in the structural analysis world (aerospace) for more than 25 years, I too have seen the same sequence of events occur over and over again.
I have a question to the engineers that believe composites are the answer to everything:
Have we really applied the state of the art in analytical techniques (FEA, etc.) in the optimization of metallic airframe structures?
In my experience, the typical metallic airframe structural designer/analyst is still utilizing the technology/methodology of the 1980's. When they shift gears to the plastics, they apply current technology. I think if there was ever a true comparison of weight of a brand new aircraft (both plastic and metallic) based upon the same level of detail in analysis (current state-of-the-art) we’d learn what I think you already know - an optimized metallic airframe could weigh the same (or less).
This whole composite debate is very strange. It takes some true cahonas to speak out as you have in this blog. My hat is off to you.
Excellent blog... I want to hear more. Having been in the structural analysis world (aerospace) for more than 25 years, I too have seen the same sequence of events occur over and over again.
I have a question to the engineers that believe composites are the answer to everything:
Have we really applied the state of the art in analytical techniques (FEA, etc.) in the optimization of metallic airframe structures?
In my experience, the typical metallic airframe structural designer/analyst is still utilizing the technology/methodology of the 1980's. When they shift gears to the plastics, they apply current technology. I think if there was ever a true comparison of weight of a brand new aircraft (both plastic and metallic) based upon the same level of detail in analysis (current state-of-the-art) we’d learn what I think you already know - an optimized metallic airframe could weigh the same (or less).
This whole composite debate is very strange. It takes some true cahonas to speak out as you have in this blog. My hat is off to you.
I'd have to agree, but if designers never expand their horizons, we'll always be stuck with aluminum tubes...
Chris
Airplanes For Sale Aircraft
Chris
Airplanes For Sale Aircraft
I know that I have just entered my career in Aviation, But I was just wondering do you think that it is worth for theese companies to continue to make these massive airplanes such as 787, and A380
Do you guys think that an aircraft made of composites would have reacted the same way as the jet in the Hudson or the Turkish 737? Not sure if the material would have hold the same way.
http://www.privejets.com/
http://www.privejets.com/
Interesting site and most timely. There is another interesting site that deals with this topic - lonelyscientist.com - that provided extensive info on all composite aircraft, including the 787 and much more. A draft text of a book on the 787 and so on can be dowloaded. recommended
autoclave- manufacturer and supplier of autoclaves and provide quality autoclaves like autoclave sterilizer, vertical autoclave, horizontal autoclaves, autoclave aluminium, autoclave double drum, dental autoclave.
Airbus has the A380, designed 10 years before the 787. My money is still on Boeing to take back some of the overall sales with 787 type aircraft. The bet the company on the 747 in the 60's - it paid off
model airplanes
model airplanes
I can't wait for the 787 to start flying! The wings look so amazing! http://www.airplanespottingbrian.blogspot.com
Brian
Brian
The Starship was a sucsess in that we learned a lot. Yesthier were mistakes made and it didn't turn out the way it was planned- that is part of the process. It isn't an iff composities will become mainstream it's a when.
Lloyd Wood Devix Prop
Lloyd Wood Devix Prop
Hi, I found your blog to be very interesting. You might also be interested in our blog www.doctorairplane.com written by Jim Callahan FAA-DER. Jim worked in Charleston on the 787 project for a year and has recently returned home to his own business. Our blog is just getting up and running, but be assured that he has plenty of info and observations to post.
Great blog!! Please check out our sites as well:
http://www.pjsgroup.com/index.php
http://privatejetgroup.com/
Thank you! Look forward to reading more!!
Please contact with any questions:
Emma Bailey
emma.bailey@pjsgroup.com
603-760-0031
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http://www.pjsgroup.com/index.php
http://privatejetgroup.com/
Thank you! Look forward to reading more!!
Please contact with any questions:
Emma Bailey
emma.bailey@pjsgroup.com
603-760-0031
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