Satellite Tracking: Guardian Angels

By Pat Gray | May 1, 2008
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Helicopter pilots are used to being the ones that provide help from above. More and more, they are getting help from on high — from birds in space.

The Los Angeles Department of Water and Power has 4,000 mi of transmission lines and a network of water reservoirs and aqueducts in California, Arizona, Nevada and Utah. It uses four Bell Helicopter aircraft, a mix of the 206L3 and 407s, to monitor those far-flung facilities, which often requires its pilots to fly over remote and mountainous terrain beyond radio range.

"Working in remote areas is one of the main reasons" the department about five years ago decided to fit its aircraft with SkyTrac’s satellite-based tracking system, said its chief pilot, Gary Yates. "We operate in areas and at altitudes where we couldn’t get flight following" from FAA Flight Service Stations.


Yates chose the relatively bare-bones version of the satellite tracking and communications systems available today. His department’s aircraft are set up just to be tracked by the system. They don’t have the ability to send text messages or make phone calls through SkyTrac. Even the basic setup has proven "absolutely phenomenal from day one," Yates said.

"There are always benefits that come up that I haven’t thought of before," he said. "I find them all the time."

For instance, he said, a recent survey flight in California happened to coincide with a ground search for a missing woman. A department helicopter spotted the woman and was radioed her coordinates to search teams on the ground.

Yates is one of many helicopter operator converts to the use of satellite-based tracking systems and services as asset-management and safety tools.

Use of these Space Age tools is most widespread among oil and gas support operations, particularly in regions like the Gulf of Mexico where helicopters fly to rigs beyond the range of ground-based radio and radar-tracking networks. They are being adopted more and more by emergency medical service (EMS) operators, both to improve their safety and their finances. In the United States, for instance, EMS operators can get reimbursed for actual distances their aircraft fly on missions, provided they can prove a flight diverted around weather instead of sticking to a beeline route. These tracking systems allow them to do that — and boost reimbursements by several percent or more during the course of a year.

For instance, Air Methods has picked Sky Connect of Takoma Park, Md. to install its voice and tracking communications system on its aircraft. With its acquisition of CJ Systems Aviation Group, Air Methods has become the largest provider of helicopter emergency medical services. It selected a Sky Connect system that includes an 11-position dialer designed to reduce cockpit workload by enabling the crew to select pre-set numbers for faster direct voice communications. The system is compatible with night-vision goggles.

The systems and services offered by companies like Sky Connect; Blue Sky Network; Victoria, British Columbia-based Latitude Technologies; Outerlink of Lowell, Mass., and Kelowna, British Columbia-based SkyTrac are also used by utilities like Yates’ operation, charter, cargo, and corporate operators, law enforcement units, mining, forestry, and training services companies, and aerial survey and sightseeing outfits.

"There is a critical mass now in terms of adoption of these systems," said Jon Gilbert, president and CEO of La Jolla, Calif.-based Blue Sky Network. "What I’ve seen is that if you’re going to deploy our system and you have 10 aircraft, you put it on two to start off. Then you learn to rely on it for your link and communications."

Yates confirmed that. When his department first installed the SkyTrac system, some pilots complained of having a "Big Brother" monitor their performance in the air. Then the department had to rent an aircraft to replace one of its Bells undergoing maintenance; the rental didn’t have a tracking system.

"The pilot complained that he felt uncomfortable. He preferred having the system," Yates said. That pilot was one who had complained about Big Brother.

That critical mass was created in large part by the decision of U.S. and Canadian federal authorities to require flight-following systems on aircraft of operators bidding on contracts to fight wildfires.

The U.S. government-owned Global Positioning System (GPS) is the dominant worldwide navigation tool and has been the anchor for most of the more recent positioning innovations used today.

Created originally to give U.S. military forces the ability to precisely identify the position of units and locate targets anywhere in the world, GPS consists (currently) of 32 satellites above the Earth at what are called medium, or intermediate circular, orbits of 10,810 nm (20,020 km). They are assigned to orbital planes separated by 60 deg of longitude. Their orbital paths are angled to the equator so each satellite climbs through latitudes up to 55 deg N and S. The paths are designed so that each "bird" passes over the same point every 24 hr (doing so about 4 min earlier each day). The bottom line is that a GPS user’s receiver generally can "see" 5-8 of these satellites at once. GPS’ precise position data and timing signal, which are encrypted, allow military users to fix location within about 339 ft (100 m) and accurately plot speed and direction, too.

The breakthrough in GPS applications came after 1983’s Korean Air Lines Flight 007. That Boeing 747 strayed 175 nm into Russian airspace on a flight from Anchorage, Alaska to Seoul, South Korea; 269 people on board were killed when a Russian air-defense fighter shot it down. Shortly thereafter, U.S. President Reagan approved giving civil fliers access to a degraded version of GPS signals that permitted position ID to an accuracy of about 1,000 ft (300 m). GPS quickly became a vital tool for civilian users.

Subsequent improvements, mainly through the incorporation of ground stations at known locations, have permitted civil avionics to calculate location more precisely than 1,000 ft. The FAA later this year plans to activate the first phase of its automatic dependent surveillance-broadcast (ADS-B) system in the Gulf of Mexico. Based on GPS, that system is intended to replace the agency’s radar-based air traffic control network.

GPS is controlled by the Pentagon. Non-U.S. users are uncomfortable relying on the U.S. military for critical civil navigation, so other countries are pursuing their own satellite navigation systems.

As great a tool as it is, GPS’ limitation is that it cannot "talk" beyond a singular function of locating your position on the Earth. It has no capability to relay voice or data, at least in the civilian world.

It is this void that the tracking-service companies have filled. The satellites most commonly used by aviation are in low earth orbits of 120-1,080 nm or so (200-2,000 km); some fly at 19,323 nm (35,786 km). That altitude, which roughly matches the Earth’s circumference, allows a satellite to stay in the same position over the Earth’s surface — hence the name of the orbit: geosynchronous or geostationary.

For helicopter operators worldwide, the ability to combine GPS position with voice and data communications has provided a wonderful tool for asset management. Operators in remote locations, such as offshore operators, flip that statement to say a wonderful tool for flight safety.

So what comes first, managerial efficiency or safety? More than likely, that depends on the type of service and the business philosophy of the user. For helicopter operators, whose assets do not follow roads, that great flexibility to go direct to a destination can sometimes get them in trouble, such as flying into clouds with rocks in them, getting lost and running out of fuel in a remote location. The ratio of asset management to safety would have to make a move toward the safety side.

A management plus is the ability to allow customers to access flight info and view the specific aircraft for which they had contracted.

A key satellite communications provider is Iridium, which operates a constellation of 66 birds at low Earth orbits of 420 nm (780 km).

Companies that combine Iridium communications services with GPS-based tracking include Blue Sky Network, Sky Connect and SkyTrac. Outerlink uses GlobalStar’s satellites, which orbit at 810 nm (1,500 km).

Once a tracking company’s equipment is installed aboard the aircraft, then an operator’s method of moving the data from the aircraft to its operations center is almost identical. The preferred word is "data burst," wherein, location, altitude, speed, aircraft ID number, and other pre-programmed information is transmitted to the satellite at a pre-set time interval of between, 15 sec up to as many minutes as you would like.

Transmissions of some of the information is automatic and does not require pilot input. There are options for more complex burst information that does require some pilot input, usually not much more than a flip of a switch. Most of the tracking service providers have a multi-select switch on the cockpit control heads that allow a number of pre-set coded messages to be sent as required by the helicopter company operations managers.

Era Helicopters, headquartered in Lake Charles, La., uses Sky Connect. Its hardware installed on Era’s aircraft include antennas, a panel-mounted control head and a Tracker transceiver. Transceivers are the heart of all the tracking systems. They have a GPS receiver that integrates with the position and data transmitters. This is transmitted to an Iridium satellite and then relayed to a ground receiver, which feeds it to a computer terminal via the Internet.

At this point, it can be picked up by Era’s software program. Even though Sky Connect promotes a tracking software program called Flight Explorer, Era differs from other operators in that it has written its own software to track its fleet. This allows it to customize and update the program as it needs to.

Era staffs its flight-following center with two full-time radio operators and a supervisor who also commands a console when needed, according to Era Communications Manager David Robinson. The supervisor of each shift is a retired Era pilot with years of flight experience and can act as a second or third pilot during an emergency situation.

From a management perspective, Era’s flight-following system is there for the safety and well-being of customers and flight crews. Any asset-management fallout is considered a bonus for flight operations.

Era President and COO Neill Osborne feels the helicopter industry has just scratched the surface of tracking-system technology. Others agree, the L.A. water and power agency’s Yates said the helicopter industry’s use of satellite tracking services is in its infancy.

Era’s Osborne said he envisions incorporating many more iterations into Era’s operations.

Rotorcraft Leasing of Broussard, La. recently decided to switch from Sky Connect to Blue Sky Network. Gerry Golden, vice president and general manager of Rotorcraft Leasing of Broussard, La., said he felt Blue Sky Network provided a more user-friendly system. Blue Sky uses its Sky Router software to feed information to terminals in Rotorcraft Leasing’s operations center.

Blue Sky provides Rotorcraft Leasing with a data burst setup. When an aircraft is below 300 ft, data is sent every 15 sec. With the aircraft at 3,000 ft or higher and within 5 mi of land, data packets are sent every 1-2 min.

For long-range planning, Golden said, he can see the day when all of Rotorcraft Leasing’s voice communication will be via satellite. He said he believes Blue Sky will be the best vehicle to get them there.

While safety is the major concern, he said, a big management plus is the ability to allow customers to access flight information, via password access, and view the specific aircraft for which they had contracted at any given time. This allows them to use the most efficiently positioned aircraft for any given flight, but only through Rotorcraft’s flight operations via telephone. Rotorcraft mans the flight following room with three operators and a supervisor per each of two shifts.

According to Air Logistic’s Director of Operations Robert Wade, the company uses several vendors. The New Iberia, La.-based company has aircraft fitted with systems from Blue Sky, OuterLink and Sky Connect. But Wade said the company plans to switch entirely to Sky Connect in the future to standardize the equipment.

On a daily basis, Air Logistics tracks upwards of 120 aircraft.

Wade said Air Logistics’ flight tracking system is in place for the safety and security of its passengers and crews and no consideration is given to management programs when designing, using or tweaking the system.

All of the offshore operators I talked to are eager to go to 100 percent satellite communications.

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