Realigning Satellites for Gulf War Hurts Southland Firms

The Persian Gulf war is posing serious problems for Southland companies that depend on satellites for everything from steering oil tankers to mapping out potential freeway routes, according to military and commercial sources.

Some industries rely heavily on a group of 16 military-run satellites known as the Global Positioning Systems, and a realignment of the satellites to aid Operation Desert Storm is already causing problems for survey companies and civil engineers. Some firms report that they are losing thousands of dollars daily because access to these satellites has been greatly reduced, delaying key projects.

Psomas & Co. in Costa Mesa, for example, depends on GPS satellites to remap California 91 for scheduled repairs, but the time it’s taking to finish the freeway project has nearly doubled. The Orange County surveyor’s office reports that independent contractors and its own crews are seeing delays of at least 25%.

“We’ve lost a third of our work day,” said Fred Henstridge, Psomas vice president.

The Persian Gulf war has pointed up a serious problem facing some businesses--a precarious reliance on a satellite system that was never intended for heavy commercial use.

GPS, which is operated by the Defense Department, has two channels: a highly accurate military signal and a less reliable civilian signal. Some commercial companies have access to the military channel and have come to depend on it.

The Defense Department’s longstanding policy is that it would restrict access to the military channel in the event of a crisis. The agency has also said it plans to encrypt the military channel, preventing its use by commercial firms, once all the GPS satellites are in place in a few years.

So some companies are increasingly worried that the Pentagon will restrict access to the GPS system exclusively to the U.S. military as a result of the Persian Gulf war.

For now, most experts believe that it is highly unlikely the military will curtail access. They point out that the Pentagon purchased thousands of civilian-band receivers in recent months because of a shortage of access on the GPS system’s military channel.

“To degrade the signal for civilian receivers would be counterproductive to their efforts in the Middle East,” said Randy Hoffman, president of Monrovia-based Magellan Systems, a supplier of satellite receivers.

What’s more, military officials don’t believe Iraq possesses the hardware it would need to use GPS.

“The government did a survey of how many GPS receivers could have been sold to Iraq and they came up with less than a dozen. So the capabilities of the Iraqis to use GPS is non-existent,” said Hoffman. “This is an extremely complex technological device.”

Should the Defense Department begin to encrypt the military channel it would create serious problems for satellite users ranging from telephone companies to scientists at the Jet Propulsion Laboratory in Pasadena. JPL researchers rely on GPS satellites to carry out earthquake prediction studies.

“I can understand the concerns of people in business. They’ve come to rely on it,” said Glen Gibbons, editor of GPS World, a Eugene, Ore., trade journal. “However, we have a war situation in the Middle East. It’s a military problem and this is a military system so it’s not a surprise they’ve given it a priority. People’s lives are at stake.”

The satellites enable troops in the Middle East or elsewhere to pinpoint their exact location within about 50 feet in all weather conditions. Using hand-held receivers, soldiers can pick up signals that are constantly beamed to Earth from GPS satellites. The signals from four satellites are needed to fix a position.

The GPS system is also a critical navigation tool for a number of weapons systems, including M-1 tanks, armored personnel carriers, fighter planes and jeeps.

Surveyors use this same technology to create three-dimensional models that eventually become highway design maps. But they require a fifth satellite to perform the necessary calculations.

When one GPS satellite failed in December, it drastically reduced the time five satellites were available for surveying purposes. The Air Force recently launched two GPS satellites--one the day of the Iraqi invasion and the second Nov. 26--and surveyors were hoping they would have access to those satellites.

Those familiar with the GPS system, however, say those two satellites were placed into an orbit to improve surveillance and coverage in the Persian Gulf. For commercial users, though, it meant less access time to the GPS network.

“The last two satellites were put up to increase coverage in the Middle East, which seems logical at this point,” said Heywood Shirer, radio navigation program manager at the Department of Transportation, which serves as a liaison on GPS for civilian users.

Officials at Psomas say they now have access to five satellites for 3 1/2 hours per day--from 6 a.m. to 7:30 a.m. and 10 a.m. to noon. Before the satellite failure in December, the company could use the system for 10 1/2 hours daily--from 6 a.m. to about 4:30 p.m.

Commercial use of GPS is extensive, particularly for land, air and sea navigation.

Burlington Northern, for instance, has begun using GPS’s military channel to track its freight trains.

The civilian channel simply isn’t accurate enough for the railroad company’s purposes.

“We need a high degree of accuracy so we can tell what track our trains are on, said Ed Butt, Burlington Northern’s director of research and development. “Our tracks are only 18 feet apart.” Butt said Burlington has begun negotiating with the Soviet Union for access to its version of GPS, called Glosnass.

American Telephone & Telegraph is using GPS to synchronize its long-distance telephone networks and has publicly protested any kind of restricted access to the military signal.

“The effect (of a shut-off) would obviously be far reaching and disruptive . . . to thousands of commercial and civilian users,” Gibbons said.

JPL physicist Ulf Lindqwister is using GPS to study movement in earthquake faults in Central America and South America. GPS receivers are placed on each of the faults, registering even the slightest of movements.

“You can see if the faults are moving and that gives you very important information about a possible earthquake,” Lindqwister said.

JPL realized though that it was taking a risk basing its project on GPS.

“It’s their God-given right” to curtail access to the military signal said Steve Fisher, a JPL researcher. “At least, that’s how they look at it.”

Missing Signals The Global Positioning System sends out precise navigational signals from a network of satelitesthat orbit the Earth twice a day at an altitude of 10,900 miles. Although a less accurate signal1769152610 Only 16 of the 21 satelites in the complete GPS network have been put in place, leaving gapsover the United States for parts of the day . Signals from three satelites are needed to determine latitude and longitude, but accurate modeling in three dimensions-such as for planning freeway routes-requires five satelites. Source: Los Angeles Times files