Oversized Satellites

Does super-size breed runaway complexity?
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Bigger is better. Right? When it comes to satellites, not every broadcaster and cable programmer thinks so. Since the late 1990s, some large and remarkably powerful communications satellites weighing up to 6 tons have been launched into orbit and service.

There is no evidence that these satellites are less reliable than the old 2-ton models. Still, they can make broadcasters a bit edgy nevertheless.

"The satellite being 22,300 miles in space calls out for simplicity," says Richard P. Wolf, vice president of telecommunications, ABC Broadcast Operations and Engineering. "Are bigger satellites with more hardware aboard a good thing? I don't think so. In my mind, simplicity wins."

To build a bigger satellite, you start with a larger satellite bus—the chassis or frame to which the solar arrays, antennas, propulsion systems, amplifiers and other components are attached. The large buses on the market today include Boeing's 702 and Alcatel's Spacebus 4000.

"We have all been burnt by satellite failures in the past five years," Wolf says. "These much larger satellites with their more intricate designs need careful managing."

"Most of the developments in satellite technology today support different business applications than what we require, such as onboard switching," says Bob Zitter, senior vice president for technology operations at HBO Time Warner Entertainment. "All we want is bent-pipe C-Band. Anything else detracts from reliability. That is what is important to us."

"Reliability is the key issue," adds Brent Stranathan, vice president of broadcast distribution at CBS. "It continues to be one of my biggest concerns particularly since so much of what makes up these additional payloads does not relate in any way to what we do. We are concerned about the additional complexity. This is simply too important to our business."

Stranathan points to Loral Skynet's Telstar 8 as a case in point. Along with C-Band and Ku-Band capacity, the bird will have 24 Ka-Band transponders aboard. Loral Skynet plans to launch the satellite at 89 degrees west longitude in March 2003.

Satellite operators are keenly aware of the users' concerns. In fact, Jim Frownfelter, executive vice president and CTO of PanAmSat Corp., readily admits that he's not a big proponent of big satellites. PanAmSat already has three of the larger 702s in its fleet including Galaxy XI, Galaxy 3C and PAS1R.

"We have a pretty even mix," says Frownfelter. "Satellite manufacturers are always pushing for bigger satellites. They will tell you that these larger satellites offer better margins across the board, and lower costs per transponder, while the operator will say that this allows him to offer more capacity at a cheaper rate."

"All of this is part of a field-of-dreams mentality—build it and they will come—which is still quite pervasive despite the excess capacity that exists in certain regions of the world," he says.

Frownfelter says his team once spent a week chasing down a short on a wire harness somewhere in what he estimated to be about 300 miles of wire on one large satellite just prior to launch. "On a smaller satellite," he says, "the same task would have taken maybe an hour."

Risk mitigation takes on a whole new meaning. If a smaller satellite fails, it is far easier to move that capacity to a backup," Frownfelter says. "When a satellite is up there with 90 transponders on board, risk mitigation is not easy. It is difficult for us and nearly impossible for everyone else."

For Zitter, the decision by PanAmSat to acquire three small C-Band STAR GEO satellites from Virginia-based Orbital Sciences was reassuring. Each weighs just 1,700 kg. The first, Galaxy XII, is scheduled to go up next year with 24 C-Band transponders, followed by replacements for Galaxy V and Galaxy IR in 2005 and 2006, respectively.

"Orbital Sciences came up with a product that meets our needs," says Zitter.

At SES Americom, additions to its satellite fleet in the coming months will include satellites larger than the satellites being replaced.

"Our design philosophy provides the highest degree of reliability and triple redundancy on mission-critical subsystems. Broadcasters can become comfortable with the right design," says Carl Capista, SES Americom's vice president of entertainment sales.

"We have no super-large buses in our fleet currently. When we do add larger satellites, either larger Lockheed Martin A2100s or Alcatel 4000s, we will be consistent in terms of onboard redundancy," says Capista. "And we also intend to add small C-Band-only satellites to our fleet in 2004 when AMC-10 and AMC-11 are launched to replace C3 and C4."

According to Joan Byrnes, chief operating officer of Loral Skynet, maintaining a fleet with a mix of larger satellites with multiple payloads and smaller satellites with single payloads is beneficial to customers.

"Satellites with larger buses and more transponders yield a lower cost per transponder. Skynet also recognizes the benefits of also having smaller, single payload satellites, which creates a more agile fleet," says Byrnes. "Having a mix of large and small satellites increases the overall reliability and robustness of our fleet."

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