A Boeing Business Jet heading to Geneva for the European Business Aviation Convention & Exhibition (EBACE) in late May marked a notable milestone by becoming the first business jet to cross the North Atlantic using future air navigation system (FANS) technology to communicate with ATC.
Flying with an upgraded Smiths flight management computer (FMC), the BBJ’s pilots sent and received short text messages during the oceanic leg of the trip rather than talking with controllers on the radio. The airplane, Boeing’s own BBJ demonstrator, flew to Geneva nonstop from the company’s flight operations headquarters in Gary, Ind., outside Chicago. Until now, the FANS technology had been used only by airlines.
Available for the last several years on North Atlantic and Pacific routes, FANS provides ATC with automatic position reports and brief messages from pilots. Controllers and pilots communicate by choosing from a list of possible requests and replies. ATC uses FANS for position reporting and monitoring reduced separation on the Pacific and Atlantic, but the required avionics are unique to Boeing and Airbus airplanes and are not available for any business aircraft (other than the BBJ and ACJ) since the corporate market is relatively small. In all, pilots flying with FANS avionics can choose from a list of about 300 preprogrammed messages.
The satcom-based concept, which uses controller-pilot datalink communications (CPDLC), was developed to reduce the number of radio transmissions for a given flight in an effort to relieve radio congestion and cut the chance for errors. At any time during a FANS flight, pilots can pick up the radio and call ATC, or they have the option of keying-in free text messages.
Mike Hewett, chief pilot for Boeing Business Jets, the joint Boeing/General Electric company that markets the BBJ, explained that HF voice, the traditional method for voice communication over the oceans, can be affected by atmospheric disturbances, leading to poor reception. As traffic in the North Atlantic Tracks increases, there is also a greater chance that pilots from different airplanes will try to talk at the same time.
“HF radio is severely hampered by sunspots and congestion,” Hewett said. “FANS clears lines of communication and ultimately gives air traffic controllers better control of aircraft in oceanic airspace.”
So far the FANS central monitoring agency has approved three BBJs to participate in the trial. Boeing anticipates that many more of the 75 BBJs currently in service will sign up in the coming months. Joining the trial involves upgrading the airplane’s FMC with new software, a new faceplate containing an “ATC” button, and audible tones to alert pilots when ATC is trying to communicate with them.
During the inaugural FANS flight to Geneva, BBJ captain Chase Loupee said the system performed as advertised, allowing the crew to link up with ATC once they reached Gander airspace and remain online until passing into European airspace, when normal voice communication was resumed.
“ATC has been handling FANS airplanes since 1997, so this is really nothing new to them,” Loupee said. “But I’m sure they consider it important since this is the first FANS crossing by a business jet.”
A Quiet Flight
From outward appearance in the cockpit, there seemed to be nothing unusual about the flight except, perhaps, that it was quieter than normal as the pilots clicked buttons on the FMC instead of keying their microphones and talking to controllers. At one point during the flight, after what seemed like a long period without any CPDLC messages from ATC, the pilots decided to send a free-text message just to make sure they were still online. Less than a minute later ATC replied that their transmission had been received.
Improved communication is only one of the features of the technology. The high degree of position accuracy provided by FANS allows ATC to reduce the buffer between airplanes and therefore safely increase the number of airplanes operating in the same airspace. Boeing Business Jets president Lee Monson, who was along for the FANS flight, said the operating efficiency and added safety should make FANS a popular upgrade with BBJ operators.
“Using FANS for private and business aviation can add another layer of safety and efficiency to the global air transportation system,” he said. “It will also allow BBJ operators to take the most direct routes, shortening flight times and saving fuel.”
CPDLC service has been available in certain South Pacific FIRs since 1995 and today is available in all Pacific Oceanic FIRs, including Tokyo; Anchorage, Alaska; and Oakland, Calif.; and is also being used in the North Atlantic Tracks and the New York FIR. Experts say CPDLC is needed because expansion of VHF voice communications with ATC in high-density areas will reach its limit by the end of the decade, when the VHF spectrum will become saturated. The move to 8.33-KHz channel spacing in Europe has helped alleviate congestion, but the additional channels that have been created are quickly filling up.
For airspace planners in the U.S., frequency congestion will become a major concern in the years ahead. The FAA’s trial of CPDLC at Miami will end soon because of the program’s high costs and limited operator participation. FAA officials have decided to discontinue the trials until nationwide implementation can be achieved following completion of the en route automation modernization (ERAM) program, which is estimated to be ready sometime between 2009 and 2011. The FAA plans to shift this year’s CPDLC operating funds to studies of a future national CPDLC strategy.
But the cancellation of the Miami CPDLC trial makes the FAA a follower rather than a leader in the rapidly advancing world of ATC technology. Eurocontrol has its own CPDLC/VDL-2 program under way and forecasts that all of Western Europe’s upper airspace will be covered by 2007, meaning that many U.S. operators will have to equip their aircraft long before ERAM in the U.S. comes online.
The CPDLC trial became the victim of budget cuts announced by the FAA earlier this year, which also saw postponements in the LAAS (local-area augmentation system) and Nexcom (next-generation communications) projects.