Composite fuselage
Disassembled fuselage section of the Boeing 787 Dreamliner
The 787's all-composite fuselage makes it the first composite airliner in production. While the Boeing 777 contains 50% aluminum and 12% composites, the new airplane uses 50% composite (mostly carbon fiber reinforced plastic), 15% aluminum, and other materials. The 787 fuselage is made up of composite barrel sections joined end to end. Each fuselage barrel will be manufactured in one piece. This will eliminate the need for some 50,000 fasteners used in conventional airplane assembly.[103] It was suggested by many, such as former Boeing senior engineer Vince Weldon, that the risks of having a composite fuselage have not been fully assessed and should not be attempted.[109][110] It was also added that carbon fiber, unlike metal, does not visibly show cracks and fatigue.[111] Boeing has dismissed such notions, insisting that composites have been used on wings and other passenger aircraft parts for many years and they have not been an issue. They have also stated that special defect detection procedures will be put in place to detect any potential hidden damage.[112]
Concerns have been raised about the porous properties of composite materials, allowing them to absorb unwanted moisture. As the aircraft reaches altitude, the moisture expands, and may cause delamination of the composite materials, and structural weakness over time.[113]
Another concern arises from the risk of lightning strikes.[114] The 787 fuselage's composite could have as much as 1,000 times the electrical resistance of aluminum, increasing the risk of damage during a lightning strike.[115] Boeing has stated that the 787's lightning protection will meet FAA requirements.[109] FAA management is planning to relax some lightning strike requirements, which will help the 787.[116]
In 2006, Boeing launched the 787 GoldCare program.[117] This is an optional, comprehensive life-cycle management service whereby aircraft in the program are routinely monitored and repaired as needed. This is the first program of its kind from Boeing: Post-sale protection programs are not new, but have usually been offered by third party service centers. Boeing is also designing and testing composite hardware so inspections are mainly visual. This will reduce the need for ultrasonic and other non-visual inspection methods, saving time and money.[118]
According to Boeing Vice President Jeff Hawk, who heads the effort to certify the 787 for airline service, a crash test involving a vertical drop of a partial fuselage section from about 15 feet onto a one inch-thick steel plate occurred on August 23, 2007, in Mesa, Arizona.[119][120] Boeing spokesperson Lori Gunter stated on September 6, 2007, that results matched what Boeing's engineers had predicted. As a result the company can model various crash scenarios using computational analysis rather than performing more tests on actual pieces of the plane.[121][122] However, it has also been suggested by a fired Boeing engineer that in the event of a crash landing, survivable in a metal plane, the composite fuselage could shatter and burn with toxic fumes.[109]
Weight issues
Boeing had been working to trim excess weight since assembly of the first airframe began in 2006. This is typical for new aircraft during their development phase. The first six 787s, which are to be used as part of the flight test program, will be overweight according to Boeing Commercial Airplanes CEO Scott Carson.[123] The first 787 is expected to be 5,000 lb (2,270 kg) overweight. The seventh and subsequent aircraft will be the first optimized 787s and are expected to meet all goals.[124] Boeing has redesigned some parts and made more use of titanium.[36] According to ILFC's Steven Udvar-Hazy, the 787-9's operating empty weight is around 14,000 lb (6,350 kg) overweight, which also could be a problem for the proposed 787-10.[125]
In early 2009 a number of 787 customers started to publicly mention their dissatisfaction with the reduced specifications on the 787, specifically weight and range issues. Industry insiders have stated Boeing has reduced its range estimates for the 787-8 from 14,800–15,700 km to 14,150–15,170 km, a reduction of over 500 km. There have also been reports that this led Delta to delay deliveries of 787s it inherited from Northwest in order to take later planes which may be closer to the original estimates. Other airlines are suspected to have been given discounts to take the earlier models.[126] Shanghai Airlines stated in March 2009 it wished to either delay or cancel its first order. Boeing expects to have the weight issues addressed by the 21st production model.[127]
In May 2009, a press report indicated that a 10–15% range reduction for early 787-8 aircraft is anticipated due to these planes being about 8% overweight. This means a range of about 6,900 nmi (12,800 km) instead the originally promised 7,700 to 8,200 nmi (14,800–15,700 km). Substantial redesign work is expected to correct this, which will complicate increases in production rates.[128] Boeing confirmed on May 7 that early 787s would be heavy and is working on weight reductions. The company stated the early 787-8s will have a range of almost 8,000 nmi (14,800 km).[129]
Computer network vulnerability
787 flight deck
In January 2008, previous Federal Aviation Administration concerns came to light regarding protection of the 787's networks from possible intentional or unintentional passenger access.[130][131] The computer network in the passenger compartment, designed to give passengers in-flight internet access, is connected to the airplane's control, navigation and communication systems.[130]
Boeing called the report "misleading", saying that various hardware and software solutions are employed to protect the airplane systems including air gaps for the physical separation of the networks, and firewalls for their software separation. Measures are provided so data cannot be transferred from the passenger internet system to the maintenance or navigation systems. As part of certification Boeing plans to demonstrate to the FAA that these provisions are acceptable.[130]
Engine interchangeability
The two different engine models compatible with the 787 will use a standard electrical interface to allow an aircraft to be fitted with either Rolls-Royce or General Electric engines. This will save time and cost when changing engine types.[132] However, ILFC's Vice President of Marketing, Marty Olson, stated that swapping different engines could take up to 15 days, and therefore would cost too much. "You'd have to take all the pylon, everything from the wing down, off," Olson said. Other aircraft can have engines changed to those of a different manufacturer, but the high cost makes it rare. Boeing said that the design is unfinished, and 24 hours is still the goal.[133]
