Friday, July 21, 2006
787 - Another View
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.
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!