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BOEING PLANS 747 DERIVATIVES

Today when one hears the term "super jumbo", one automatically thinks of the Airbus A3XX. The European 555-seater is not, however, the only aircraft in this class. Boeing is currently working on some new variants of the 747-400, with the specific aim of prising market share away from the A3XX.

The Boeing 747 is a success story that is unrivalled in the history of commercial aircraft. For more than 30 years it has not had any competition. To date, over 1,100 Jumbo Jets have been delivered. And if Boeing's forecasts as to the shape of future market trends are correct, then it is not worth investing money to develop a rival to the 747, as the market is only small. Airbus Industrie sees things differently. Direct comparisons between the two manufacturers' market forecasts require close examination of the data. Boeing regards aircraft with over 400 seats as a single market segment, whereas Airbus defines aircraft with more than 500 seats as a market segment in its own right. Only when one studies the analyses in detail does it become clear that Boeing expects world-wide demand for aircraft in this category between now and 2018 to total 365 aircraft. Airbus expects this market segment to grow significantly more strongly and anticipates a requirement for up to 1,200 aircraft over the next 20 years.

Given its more conservative forecasts, Boeing's assessment is that such a small market does not warrant a completely new aircraft. Instead, it plans to satisfy airlines' needs with a new version of the 747 family. The variants proposed depart from earlier proposals in that the upper deck runs for only part of the length of the aircraft.

If sufficient orders come in, Boeing plans to launch the 747X in 2001. Boeing President Phil Condit said in Seattle, "The programme can be formally launched within six to nine months. I am assuming that by then we will have received between 10 and 30 orders for the new 747."

In June, the biggest aerospace company in the world gave a presentation to the airlines in Seattle on three variants: the 747-400X, the 747X and the 747X Stretch. The 747-400X can be implemented as the first aircraft in the new family. Externally it looks just like today's 747-400, but the interior will receive a new lease of life so as to offer customers either more range or more payload. Modernisation will entail the use of new materials which will make the aircraft lighter than today's 747-400. This will enable routes such as New York - Hong Kong to be flown non-stop in future with a full payload.

Assuming the programme is launched, the cockpit and passenger cabin will be brought in line with those of the 777. This 747 wariant could enter service with the airlines as early as 2002.

The second variant Boeing plans to market is the 747X. The aim is to launch this at the same time as the A3XX. However, the 747X will require a lot more work to achieve the objectives which have been set. Total development costs for the 747X are expected to come to around $4 billion. But, according to Boeing Chief Financial Officer Mike Sears, "this sum includes tooling for full production. We won't be doing any business which will not mean offering our shareholders more value than up to now."

The major part of the development money will be swallowed up by the design and construction of a modified wing. The wing surface area will grow by 17% and the span by 8%, while at the same time the wing will accommodate 27% more fuel than today's 747-400 wings. The wing span of the 747X will be 69.77m, compared with 64.44m on the 747-400.

The 747X cabin will have the same design as the 777, although the latter only takes 442 passengers in a typical three-class configuration. Moreover, in the aft section of the passenger compartment the empty space above the passenger cabin will be used to provide a crew rest area for use on very long flights.

To achieve the desired aircraft efficiency new engines will be required. There are two candidate powerplants, one from the Engine Alliance, a company jointly owned by Pratt & Whitney and General Electric, and a turbofan from Rolls-Royce. Both models are also competing for selection on the A3XX. Boeing believes that the engineers will succeed in making the aircraft quieter than the A3XX even though its powerplants are identical. All these engines are in the class around 68,000lb take-off thrust.

The third variant Boeing is proposing to the airlines is the 747X Stretch. This would have a three-class capacity of 522 passengers, making it only slightly smaller than the A3XX. The 747X Stretch will be a 747X lengthened by a further 7.10 m and, at 80.60m, would be the longest 747 ever developed. The longer the faster, as they say at sea, and now this is to apply to aircraft construction as well. John Roundhill, Vice-President of Commercial Airplanes' Product Strategy and Development at Boeing, said at the Farnborough Airshow that studies suggested that operating costs for the 747X Stretch would be around 10% less than for the A3XX. In addition, seat mile costs of the 747X Stretch would be between 3 and 5% lower than those of the rival European product. But lengthening the fuselage comes at a price: the range of the 747X Stretch, at 14,450 km (7,803nm), will be 2,200km (1188nm) less than that of the 747X.

In addition to the work on the 747, Boeing is also studying the next generation of passenger aircraft in detail. Under the project title "Boeing 20XX" a whole new generation of commercial passenger planes with a conventional design is taking shape. Within the company, this concept is up against a highly unconventional passenger aircraft concept, which a research team is developing at Boeing's "Phantom Works". Phantom Works is working on technologies which depart radically from today's approach to aircraft construction. The flying wing "blended wing body" (BWB) concept is one of these. It was originally developed by McDonnell Douglas but was acquired by Boeing when the two companies merged.

Phantom Works has flown a model with a wing span of 3.5m (11.5ft) in collaboration with NASA which has demonstrated the aerodynamic efficiency of the concept. The next step, a model with a wing span of over 11m (36ft), should take to the air later this year.

FLUG REVUE spoke to George K. Muellner, General Manager of Phantom Works. "Three different versions of the BWB are possible, corresponding to passenger capacities of 250 seats, 450 seats, and 600 seats. As well as aerodynamic efficiency, a major advantage of this aircraft configuration is that all three versions can be manufactured highly efficiently due to their largely identical construction."

The fact that the company has spent around DM2 million ($950000) in recent months testing the acceptance of such an aircraft and specifically of its passenger cabin on passengers shows that the idea is not just a fantasy inside Boeing. This issue is extremely important for an aircraft which is to have a passenger cabin the size of a ballroom but in which there will be no windows. Instead of windows, passengers will be able to gaze outside via large, individual screens. Exterior cameras will allow passengers to look where they like. According to Muellner, "our trials show that the screens are very popular with passengers."

For the airlines, operating costs are likely to be the primary consideration. And thanks to a 15 to 20% improvement in efficiency, these should be far below the costs of operating conventional aircraft. If the objectives are achieved, it will then be necessary to overcome psychological barriers amongst airlines and passengers which could prevent implementation of such an aircraft family.

If in 1997 NASA was working on the assumption that a flying wing passenger aircraft could enter service no earlier than 2020, today Muellner believes it can be realised much sooner than that: the first member of the Boeing flying wing family could be flying in 2008 and enter passenger service in 2010. He told FLUG REVUE, "The technology will be available by then. But whether such an aircraft gets built only the market can decide. 2005 has been set as the year we make a decision." Even if this aircraft configuration is not taken up in the civilian sector, there are other, military applications where it could be used. According to Muellner, "The next generation of tankers will be a flying wing aircraft with a range of 18,000 to 20,000 km" (9700nm to 10,800nm).

Boeing President Phil Condit told FLUG REVUE in Seattle, "What it boils down to is do we understand our customers better than the competition and can we respond more quickly?" The answer will come from the airlines over the next few years.

From page 36 of FLUG REVUE 9/2000

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