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Take Off, Plug In, Dial Up

Coming to a plane near you: e-mail, Web surfing, cell phones, and more

12 min read
Take Off, Plug In, Dial Up

You couldn't help but stare at the e-mail inbox. Were these messages for real? It used to be just the corporate jet set and desperate suits who were willing to shell out the US $10 a minute to hook their laptops up to seatback phones in order to send e-mail. Is inflight e-mail finally becoming a reality for the masses?

Indeed. As the plane-to-plane exchange of e-mail—a clever marketing gimmick staged by Tenzing Communications Inc., Seattle, Wash.—showed, commercial airlines are now looking to deploy a slew of new inflight technologies for business as well as entertainment. And competition is fierce: in recent months, Tenzing has signed up seven airlines for its narrowband Internet and e-mail service, and airplane manufacturer Airbus, headquartered in Toulouse, France, has bought a 30 percent stake in the company. Meanwhile, Connexion by Boeing (a Boeing Co. subsidiary based in Irvine, Calif.) has lined up American, Delta, and United airlines for its broadband inflight service.

fly01.jpg At the annual Inflight Passenger Entertainment and Communications Conference in London last April, some 400 attendees got a taste of what's coming from the likes of Tenzing, Boeing, Thales Avionics, General Dynamics, and Rockwell Collins. E-mail is on the way, as well as Web surfing and on-line shopping, cellular telephone and wireless modem use, and live radio and television. The inflight entertainment market is huge and growing: some $2.4 billion at present, with projected growth to $7.4 billion by 2007, according to research firm Frost & Sullivan, based in San Jose, Calif. The goal is to keep frequent fliers connected to their cell phones, Palm Pilots, and the Internet long after the seatbelts have been fastened, tray tables stowed, and the plane has climbed to 40 000 feet.

It's enough to make even the weariest road warrior forget about the airplane food and flight delays—well, almost. No technology is that advanced.

Coffee, tea, or e-mail?

The flurry of airborne data services comes as airlines scramble to win over business travelers, who now make up roughly half of all fliers—about 40 million annually worldwide—and the lion's share of the airline industry's profits, and tend to expect better service.

"It's seldom you can take eight hours out of a business person's life and not have them miss something," said Terry Wiseman, publisher of Airfax, a newsletter covering the inflight entertainment industry. "Airlines are now paying the equivalent of a jet engine" to equip a plane with inflight systems.

"There are some killer applications coming to the aircraft, the main one being e-mail," Wiseman added. Delivering e-mail and Internet access to passengers can be done in two ways: narrowband and broadband. High-speed networks on board the aircraft, meanwhile, distribute data, as well as power, throughout the cabin.

Frequencies assigned to various narrowband and broadband inflight services range from 1-40 GHz.

Spectrum Spanned by Inflight Entertainment: Frequencies assigned to various narrowband and broadband inflight services range from 1-40 GHz. Click on the image for the full illustration view.

Narrowband Think slowing down to go forward. For the next year or two, broadband connections will remain too expensive, and so some carriers are opting for narrowband connections, a less expensive, but more limited approach. Narrowband aggregates, compresses, and transmits e-mail at very low speeds to the Internet. Similarly, Web surfing is limited to sites that have been cached in on-board servers before takeoff. For those accustomed to instant messaging and T1 connections at the office, narrowband can seem painfully slow or limited. Cost is its main advantage: narrowband installation ranges from $30 000 to $50 000 per aircraft and takes about five hours, compared to broadband's $4 million and two weeks.

To send and receive e-mail, a passenger plugs her laptop into the seat-back phone, which dials an on-board server. The laptop transfers e-mail at 56 kb/s to the server, which stores and compresses bundles of messages before sending them at 2.4- 9.6 kb/s at UHF, 1-2 GHz (L band), or 18-27 GHz (K band), depending on the aircraft. (The lack of real estate in the 1-40-GHz radio frequency spectrum preferred by inflight service providers means that separate frequencies are often allocated for communications from the ground to the aircraft, aircraft to satellite, and so on; see figure.)

The e-mail bundles are sent every 15 minutes to ground servers, which then send the data to the Internet or to corporate accounts. The ground control system also pulls the user's e-mail from the Internet, then bundles, compresses, and transmits it to the plane at the same speeds. Signals to and from the ground travel by way of the North American telephone system during flights over North America and by satellite over the ocean and elsewhere. This setup also lets passengers on the same flight bypass the Internet and instead communicate with each other through the on-board intranet.

Despite the 15-minute delay, "to the end-user, the experience is invisible," said Stuart Dunleavy, director of strategic alliances at Tenzing, the leading narrowband service provider. "They just sit there, merrily working away, and their e-mail will pop up. When they hit SEND on their laptop, it goes to the server. Even if you send the message just before the cabin attendant says, 'Close down your laptop,' we'll send it off when the aircraft lands."

Other narrowband service providers include Tustin, Calif.-based Airshow Inc., which started its service in corporate jets last fall, and Fort Lauderdale, Fla.-based inflightonline Inc.

Broadband In the long run, the future for both commercial and corporate jets is clearly broadband. Transmitting data to and from aircraft via satellite, broadband replicates a user's Web surfing experience on the ground.

"You don't want a dial-up experience and access to cached Web sites if you're accustomed to cable or DSL-like speeds and live Web sites," said Terrance Scott, director of communications for Connexion by Boeing, the big player in this arena. "Broadband is the only technological capability that allows you to have real-time open access to the aircraft, enabling you to transmit high-speed data files, send and receive e-mail, and have real-time access to corporate intranets."

Pending approval from the Federal Communications Commission (FCC), in Washington, D.C., which allocates spectrum in the United States, Connexion's system will send 5 Mb/s of data at frequencies of 11.5-12 GHz, returning 1.5 Mb/s at 14-14.5 GHz, using Loral Skynet satellites in both instances. So far, Connexion has U.S. approval for a receive-only license, but expects its two-way license by year-end. The 12-18-GHz band is desirable because it offers more bandwidth. But traditionally, the FCC and the International Telecommunication Union (ITU), the Geneva, Switzerland-based group that allocates international spectrum, have not allowed aircraft in flight to transmit in this band, for fear it might interfere with approved users. As Connexion awaits the 2003 meeting of the ITU's World Radiocommunication Conference, the global gathering at which major changes in radio- frequency use are hammered out, it is working with ITU's member countries toward a global allocation for the service. If all goes according to plan, Connexion and hardware partners Mitsubishi Electric, Loral Skynet, and Alenia Spazio will launch the broadband service in 2002.

In another venture, Tenzing and satellite communications firm Hughes Global Services are planning a system that transmits 8 Mb/s of data by the 12-18-GHz Ku band from satellites to aircraft and 1.5 Mb/s by the 27-40-GHz Ka band from aircraft to satellites. The system will not be available before 2003, when Hughes plans to launch more satellites with 27-40-GHz transponders. In the interim, Tenzing will offer asymmetric broadband service starting next year. Traffic will move at 8 Mb/s to the aircraft, returning to the ground via Inmarsat satellites at 2.4-64 kb/s.

In the meantime, Airshow plans to test a broadband system later this year that delivers up to 144 kb/s of bidirectional data, using data terminals developed by Qualcomm and Globalstar's low-Earth-orbit satellites. Data beams from ground stations to satellites at 5.1-5.3 GHz; from satellites to aircraft at 2.5 GHz; from aircraft to satellites at 1.6 GHz; and from satellites to ground at 6.9-7 GHz. On-board, an Ethernet server delivers Internet, e-mail, video, and telephony services.

Generally speaking, low-Earth-orbit satellites, which travel 500-2000 km above the earth, offer less transmission lag time and require less power to transmit than do satellites in higher orbits, but are harder to track, because they do not remain in the same spot over the earth. Geostationary satellites, in contrast, orbit at about 35 800 km, so they see about one-third of the planet's surface at a time; the costs are longer lag times and more power to transmit data. Their fixed positions make them easier to track, however.

High-speed LANs The advent of on-board Ethernet and universal serial bus (USB) ports will allow connection speeds beyond 56 kb/s throughout the aircraft. General Dynamics Corp., of Falls Church, Va., for example, has introduced a wired high-speed IEEE 1394 local-area network (LAN) called EmPort, which connects laptops to an on-board server through USB ports at 1.5 Mb/s. Hong Kong's Cathay Pacific Airways Ltd. recently began installing EmPort LANs for use with Tenzing's narrowband e-mail service.

By the end of the year, Tenzing, along with Scandinavian Airlines and hardware partners Miltope and Nokia, hopes to have successfully tested a high-speed wireless LAN, built to IEEE Standard 802.11b, that connects computers to ceiling access points within the aircraft; speeds may go up to 11 Mb/s, depending on the number of users. Meanwhile, Airbus will begin testing wireless connections within its aircraft this September, for fleet installation in 2002.

Who's got the score?

Forget those abridged, second-run movies. Broadband will open the door to live TV and more personalized content.

"Once you're plugging in at very high bit-rates, you not only have the ability to e-mail and Web-surf at extremely fast speeds, but also have the basis for an entertainment system," Airfax's Wiseman told IEEE Spectrum. Rather than storing and delivering content on videotape, the job will be done digitally. The next stage is DVD-based systems. Eventually, though, all content will be sent by satellite.

That in turn can reduce airplane ground time. "There's a strong desire to simplify the seat wiring, boxes, weight, and the number of systems," said Mary Rogozinski, United Airlines' manager of onboard systems planning. "With satellite links, you don't have to worry about the right video and audio being loaded each month or having enough downtime on the ground."

Like e-mail, live satellite-fed television and music have been around on corporate jets since Airshow premiered the first system in 1997. But they first appeared on a commercial airline only last year, when New York City-based budget carrier JetBlue Airways debuted 24 channels of live television. The programming, delivered to seatback displays, is supplied by DirecTV, and the entertainment system is furnished by LiveTV, a joint venture between Harris Corp. and Thales Avionics [Illustration].

artist's rendering of the new iSeries of inflight entertainment systems from Thales Avionics

More bandwidth, if not more legroom: an artist's rendering of the new iSeries of inflight entertainment systems from Thales Avionics highlights the flat-screen 10.4-in. color display and programmable handset. Airbus will flight-test the iSeries this fall.

Later this year, Airia Ltd. of London, with hardware partner Ball Aerospace & Technologies Corp., of Boulder, Colo., will launch two satellite-streamed news and sports channels. The service "follows the sun," transmitting major games from various parts of the world. When it's morning in Europe, for instance, Asian and Australian events will be shown; in the afternoon, European events; and through the night, U.S. events. Programming will be sent from a ground station to an Inmarsat satellite to the aircraft's antenna. On-board, the programming will then be transferred through a receiver box to the seatback display.

Connexion will introduce five channels of television on a high-resolution overhead screen and four low-resolution channels to laptops. Tenzing, meanwhile, has opted to form partnerships with existing providers of live TV, rather than developing its own system.

Whereas Airia, Airshow, and Connexion use existing satellite infrastructure, AirTV (a partnership of Alcatel, Arianespace, CMC Electronics, and SITA) plans to build a system from scratch. The $1 billion venture aims to launch four satellites in 2003 and to begin offering 40 channels of live TV and e-mail the following year.

The AirTV system will be the first geostationary S-band—that is, 2-4 GHz—satellite constellation having global coverage, explained Richard Stone, AirTV's executive vice president of content and programming. The advantage of using that band is that it is a single global frequency already cleared by the ITU, he added. The satellites will also offer 80 Mb/s of bandwidth and, thanks to a proprietary antenna design, reach as far north as 85 degrees—enough to cover the arctic routes used by many transcontinental flights—or about 15 degrees farther than other satellites.

The goal of all these efforts is a flexible program that changes with the demographics, culture, language, and entertainment/Internet usage of each flight's passengers. European, American, and Asian customers have different needs, said Ralf Wolckenhauer, head of cabin electrical systems for Airbus. "A cricket game in England is not of interest to Americans. American football is not of interest to people in Europe. In the United States, you might deal with two or three languages. But in Europe, you deal with 10 to 15." Tailoring content to suit individual passengers is tricky, but, said Wolckenhauer, "that's a first requirement."

Electronics companies are also vying to ensure that any new programming is worth watching and listening to. Bose, Dolby Laboratories, and Long Prosper Enterprise, for example, now offer noise-canceling headsets that significantly cut the typical 85-dB cabin din and block the lower frequencies that have been found to cause fatigue over prolonged periods. [Dolby's latest efforts are described in "Surround Sound Takes to the Air"

"Airlines are spending millions of dollars on all this wonderful inflight equipment, but not delivering the full benefit of it to passengers because the cheap headsets don't perform very well," observed Hratch Astarjian, a project manager in Bose Corp.'s Noise Reduction Technology Group. "As such, the airline itself is not getting the full benefit of its substantial investment."

Ma Bell takes flight

News flash: it's not the U.S. Federal Aviation Administration that prohibits cell phone use on commercial airlines. It's the FCC.

"There's no proof that cell phone use does or doesn't interfere with navigational systems," said Bill Singley, chairman of the Chicago-based World Airline Entertainment Association's (WAEA's) wireless working group and a former director of business development for Nokia. "The FCC doesn't allow cell phone use on airplanes because it wreaks havoc with ground telephone systems."

Airplanes travel so fast that cell phones used en route have to switch ground servers every few seconds and possibly connect to multiple towers at the same time. That saps processing power and interferes with ground-based transmissions. Multiply that by the hundreds of thousands of passengers who would likely use cell phones each day, and you get a load of busy signals.

One work-around is to fit the airplane with a so-called pico cell, which acts as a local cell tower. The pico cell connects to an on-board telecommunication server, which transmits to ground towers on a licensed frequency that does not interfere with ground-based cellular systems. The cost ends up being slightly more than a long-distance or international cell phone call on the ground.

AirCell in Louisville, Colo., currently offers a more expensive option for business jets. It routes calls through a proprietary radio tower system, which acts as an intermediary between the plane and the regular ground telephone system. With this setup, cell phones can also transmit to an on-board pico cell, but the communication is on a licensed frequency received only by those jets that subscribe to the service. Passengers can receive inflight calls by programming their cell phones to call-forward to the AirCell system, which then routes the calls to the jet.

The most successful system will recreate the experience that passengers have on the ground

Pico cell systems for GSM (global system for mobile communications) cell phones are being developed by companies like BAE Systems, interWAVE Communications, and Verizon (which now owns the inflight GTE Airfone service). But installation has to wait until airlines can accommodate cell phones of all types. In particular, phones with code- and time-division multiple access (CDMA and TDMA) systems will need to be reprogrammed to prevent them from interacting with on-board pico cells and ground towers at the same time. [See "The Standardization Debate"]

If the CDMA and TDMA systems don't change, said Singley, "personal cell phone usage on commercial flights is about one and a half to two years away, when the cellular industry moves to new and more powerful operating systems," like G3 and wideband CDMA.

Choose or lose

Just what systems and which companies will win out in the inflight entertainment wars is anybody's guess. "The most successful system will recreate the same experience that you have on the ground," predicted Kent Craver, Continental Airlines' on-board product marketing manager. "But it won't work if it's priced too high, or priced right but not adding value."

Traditionally, inflight entertainment has had a slow return on investment, of anywhere from five to 10 years. Airlines are still smarting from the spectacular unpopularity of seat-back phones. They now face a similar choice: should they go with a simpler but less expensive e-mail, TV, or telephony service today? Or should they wait two years and pay more for services that replicate land use and cater to a culturally and linguistically mixed audience?

The inflight entertainment industry has already racked up its share of false starts. United Airlines and British Airways found themselves embroiled in a bitter lawsuit with the now-defunct GEC-Marconi InFlight Systems when the latter's interactive video system failed to work. The Canadian Transportation Safety Board is still investigating whether faulty wiring in an on-board server caused a cockpit fire that led to the crash of a SwissAir MD-11 in 1998 [see "How Safe Is It?"]. And last April, Rockwell Collins pulled out of the Inflight Network, its venture with media conglomerate News Corp., after deeming the inflight service provider market too risky. Those experiences, coupled with the investment cost, have made many airlines cautious about next-generation inflight entertainment.

According to industry consultant Samuel Carswell, "Right now, a lot of money is being laid out for a very small number of passengers to access [broadband] service on a pay-as-you-go scheme. But the service won't make money until it is installed on whole fleets of aircraft and frequent fliers have signed up for monthly subscriptions."

Tacking the cost of inflight services onto tickets is universally regarded as a poor strategy. Instead, payment schemes range from pay-per-use and pay-per-flight to monthly subscriptions for e-mail. Live TV has been proposed as a pay-per-view or pay-per-flight service, with price predictions running anywhere from $5 to $20 per flight. Advertising could help offset costs, as could cross-promotions with duty-free shopping.

"People are looking at black-and-white numbers to prove return on investment, but it's not that easy to validate whether a product is giving you a new customer or retaining a current one," said Rogozinski of United Airlines. Its appeal to date has been as an airline brand differentiator.

Airlines are looking for systems that can be easily upgraded, she added. "Installing a system means ripping out the seats, the floors, the sidewalls. We can't do that every time we need something. We want to make sure it's a product that really works and that the customer is willing to pay for."

Jean Kumagai, Editor

About the Author

SUSAN KARLIN is a Los Angeles-based journalist (skarlin@aol.com) who has written for The New York Times, Forbes ASAP, Newsweek International, and Discover.

To Probe Further

The technology committee of the Chicago-based World Airline Entertainment Association helps specify the system architecture for various in-flight entertainment technologies; see its Web site at https://www.waea.org


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