Intercontinental business jets
A look at current business aircraft development shows large-cabin long-range transonic jets will lead the way.
By Don Van Dyke
ATP/Helo/CFII. F28, Bell 222
With a projected cruise speed of M1.4, the Aerion SSBJ is shown in this graphic flying off the coast of Africa—a transatlantic sector well within its 4200-nm design range from North America.
Future business jet development goals are clear—meet operational needs of capacity, speed and access with quieter, cleaner, increasingly reliable and energy-efficient airplanes.
US President Obama's State of the Union address sets a challenge to "out-innovate, out-educate and out-build the rest of the world." In this, air transport is key to US competitiveness.
Business jets are used mainly to transport high-value passengers, including heads of state and government officials, business executives and subject matter experts. The global mobility afforded permits leaders to manage multiple engagements like military missions, medical pandemics, disaster relief efforts, or sales and marketing.
The core value of business aviation is its ability to reach destinations and meet schedules beyond the limitations of airlines. Fewer than 3% of business jets are used privately.
Large-cabin intercontinental business aircraft
Bizjets are grouped loosely by cabin volume, range and price. Those most closely resembling airliners are large-cabin intercontinental aircraft (usually under 100,000 lbs MTOW) accommodating 8–19 passengers and 2–4 crew and capable of reaching destinations between 2800 and 6750 nm distant.
Typical cruising altitude is FL510, while cabin altitude is held to 5000–6000 ft. Prices range from $37–60 million each. When it comes to plans to purchase, 40% of aircraft considered in 2010 were large-cabin types, representing 70% of the dollar value of forecast sales. Most of these sales were expected in Europe and the Middle East, but the prolonged recession affected all demand channels and is not expected to ease until 2012.
Centered on New York as an example, great circle distances show the reach of typical large-cabin intercontinental business aircraft.
Range, size and speed needs drive the business aviation market and, in turn, aircraft development. Current designs have the potential to achieve and improve on these goals—but manufacturers must manage the risks of incorporating new technologies and customers must decide how much they are willing to pay for enhanced capabilities and efficiencies.
Range. Current demand reflects the increasing need for aircraft capable of transpacific flights as well as growth in demand in other regions requiring more long-range operations. Range goals (to be satisfied by the Gulfstream G650 in 2012, the Bombardier Global 7000 in 2016 and the Global 8000 in 2017) will outpace desire for greater speed to at least 2020.
Size. The market shift to larger aircraft classes derives from needed range and preferred cabin volume. However, the attendant weight may preclude operations at airports with weight limitations or may require sacrificing range. The G650 is just under the 100,000-lb weight limit at ASE and TEB, but the Global 8000 weighs almost 105,000 lbs and the Global 7000 over 106,000 lbs.
Speed. The G650 leads presently as the fastest civil aircraft, with maximum operating cruise at Mach 0.925. Subsonic speed, while important, will only become an object of competitive attention once greater range objectives are met.
Development of the Gulfstream G650 continues, the aircraft having recently reached Mach 0.995 as part of its flight test program. When it enters service in 2012, the G650 will be a market leader in terms of speed and range.
Interestingly, the results of a recent NASA study of 4 concept aircraft—meeting aggressive environmental goals—for the 2030–35 period—showed common themes such as cruising slower (M 0.70–0.75) and higher (45,000 ft) than today's aircraft to reduce drag and save fuel.
Performance goals and innovations
NASA's goals for 2030 aircraft are as follows.
• A 71-dB reduction below current noise standards
• Reduction of greater than 75% below ICAO CAEP/6 NOx emission standards
• A greater than 70% reduction in specific fuel consumption to reduce greenhouse gas
• Ability to exploit metroplex concepts enabling the use of runways at multiple airports within metropolitan areas
Breakthrough technologies can be applied to deliver more efficient, cost-effective and operationally superior aircraft. However, these yields rely on promised enhancements in air traffic management such as the use of automated decision-making tools for enroute spacing and during departure climbs and arrival descents.
Powerplants. Recent engine innovations yield significant fuel savings, reduced emissions and improved noise containment. The 4 designs most visible today are described below. The PW1000G geared turbofan is included for its remarkable potential for fuel saving.
Extended diversion time operations (EDTO).
FAA exempts private jets from ETOPS, but they remain subject to the ETOPS 120-min rule in EASA/JAA jurisdiction. Global mobility, reach and deployment requirements, as well as possible insurance standards, imply that long-range business aircraft will—voluntarily at least—meet 180-min ETOPS rules.
Fuels. One universal aviation goal is to reduce dependence on traditional carbon-based fuels. Doubts regarding alternative fuels in long-range business aviation may soon be settled under a contract awarded by Qantas to a US-based renewable energy company to study the sustainability of algae-based aviation fuel. Moreover, approval of biofuels for use in aircraft is expected by mid-2011.
Smart/multifunctional materials. Carbon nanotubes exhibit extraordinary strength and unique electrical properties, and are efficient thermal conductors. Atomic-level avionics are another future possibility.
A nanotechnology-based polymer is being tested on aircraft as an acrylic exterior polish to reduce fuel burn by 1–2% by smoothing the aircraft's surface to prevent collection of debris.