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Sunday, April 1, 2007

ADS-B in the Gulf

Offshore oil helicopters plying the Gulf of Mexico will be early adopters of ADS-B, but equipage requirements must be resolved

Douglas W. Nelms

While not renowned for its speed in implementing programs, FAA is working quickly to replace the nation’s aging, radar-based air traffic control system with one based on Automatic Dependent Surveillance-Broadcast (ADS-B). Helicopter operators in the Gulf of Mexico will be near-term benefactors of ADS-B technology, but questions remain over standards and equipage.

What is known is that under a program brokered by Helicopter Association International (HAI), helicopter operators and offshore oil platform owners will provide FAA with space for ADS-B ground and weather stations on a set number of oil rigs as well as transportation to and from the rigs for FAA personnel. Services provided to FAA are worth an estimated $100 million over the next 20 years.

The parties will "establish a cooperative government/industry business relationship to enhance communications, weather and surveillance capabilities in the Gulf of Mexico," states the memorandum of agreement signed last May.

Although studies have not indicated a precise number of oil rigs to be involved in the program, it is estimated that 20 to 30 platforms will be equipped with ground control stations. Some platforms will have co-located weather stations to provide weather information required by pilots.

Both economics and safety are behind the need for ADS-B in the Gulf.

According to HAI, more than 650 helicopters currently support some 5,000 offshore oil and gas platforms scattered throughout 899 named oil fields. The fleet logs an average of 7,500 trips daily, or roughly 50 percent of the world’s offshore helicopter traffic.

On an annual basis, Gulf helicopters fly about 380,000 hours, performing 2.1 million operations and transporting 2.6 million passengers.

All of this is done over a 500-mile swath along the Texas, Louisiana and Mississippi coastline and extending some 250 miles into the Gulf. An area of roughly 60,000 square miles in the central section of the Gulf is outside of radar control.

"The majority of helicopters operating offshore in the Gulf of Mexico do so without the ability to communicate with, or be seen by air traffic control, and without the infrastructure to provide current weather information, or other generally expected services as provided to similar operations when conducted over land," said HAI President Matt Zuccaro.

When the weather drops below VFR minimums, service to the oil rigs is reduced by up to 95 percent, having "a significant negative economic impact on offshore gas and oil activity, costing several million dollars a day," Zuccaro added.

Mark Fontenot, chief pilot for Air Logistics, New Iberia, La., and vice chairman of HAI’s offshore committee, said an original initiative was simply to get FAA "to support what they legislate."

Under FAR Part 135 governing charter operations, operators are required to have weather reporting and communications capability.

"Unfortunately, the communications were so lousy [in the Gulf], it was almost impossible to do," Fontenot said. "Secondly, we wanted to get out of the weather business, since we were having to do weather reporting to satisfy the Part 135 requirements.

While the benefits of providing full surveillance coverage to low-flying helicopters is obvious, FAA also is looking to high-altitude operations over the Gulf.

Oil rig "ground stations" will provide ADS-B surveillance for fixed-wing aircraft going to and from Mexico and Central and South America.

"One thing we really wanted to get [is coverage for] the high-altitude operations coming into Houston Center," said Vincent Capezzuto, FAA program manager for ADS-B.

"We were treating that as oceanic separation standards. We were using 30-mile separation standards, and we have a demand specifically during the spring months to Mexico, such as Cancun," he said.

"We can now economically provide a more efficient system and let [aircraft] separate closer. We’ve even gotten them down to five miles separation. So you’ve got this huge savings in fuel for the airline operators. But we couldn’t get boxes on the ground to see the signal unless we had access to the platforms. This is where the HAI came in," he added.

A final rule on nationwide deployment of ADS-B is expected to be issued by 2009, with a compliance date of 2020. "You’ll get a 10-year period to comply, but you have to figure that there are over 200,000 [general aviation] aircraft that will have to be retrofitted, and probably on the order of 3,500 air transport aircraft that will have to be equipped," Capezzuto said.

ADS-B equipage

What onboard equipment will be required? According to Cole Hedden, vice president of business development for Aviation Communication & Surveillance Systems (ACSS), the joint venture of Thales and L-3 Communications, participating aircraft will require GPS, a transponder capable of "squitting" ADS-B data twice a second, a Traffic Alert Collision Avoidance System and an interface with the aircraft that provides basic flight data such as heading, altitude and airspeed. "And in the future it will need intent data — what the aircraft intends to do," Hedden said.

ACSS, based in Phoenix, is outfitting the UPS fleet of Boeing 757s and 767s with ADS-B capabilities for operations into the cargo carrier’s Louisville, Ky., hub. The company’s SafeRoute suite of ADS-B software provides Surface Area Movement Management during taxi and in-flight merging and spacing capabilities.

Early trials for ADS-B operations over the Gulf were done with transponders operating at 1090 MHz, although these were conducted with a Gulfstream III provided by NASA and the FAA Tech Center’s Boeing 727.

Edward DeLuito, director of business development for Sensis Corp., Syracuse, N.Y., said there could possibly be two different systems available for ADS-B operations. Sensis was involved in two studies to determine the viability of ADS-B data transmitted by aircraft to ground stations for processing, determining whether the data was comparable to conventional radar.

The company also is part of the Lockheed Martin team that recently responded to a screening information request as a potential vender for ADS-B broadcast services (see sidebar, p. 40). "The 1030/1090 MHz band is reserved for air transport applications, high-altitude operations over the Gulf," DeLuito said.

"In Alaska [under the Capstone program], they wanted lower-cost avionics for the GA guys who do a lot of bush flying. So they decided on a different frequency band [978 MHz] and a slightly different technology. They used Universal Access Transceivers, or UAT. It’s just another radio method of doing ADS-B, using a lower frequency band and lower cost avionics for the GA guys," he said.

Air carrier and private operators of high performance fixed-wing aircraft will use the Mode S 1090ES system, or Extended Squitter, for ADS-B links. Companies such as Honeywell, Rockwell Collins and ACSS already are adding the ADS-B extended squitters to their Mode S transponders to meet the future 1090ES requirements.

Until the issuance of a notice of proposed rulemaking (NPRM), however, it is unknown which frequency will be used for helicopter operations in the Gulf. The NPRM is expected in September.

The primary ADS-B components used in Alaska, which could represent a low-cost package for low-flying helicopter operators in the Gulf, are the Garmin GDL 90 ADS-B UAT, linked to the Garmin GMX 200 multifunction display and GNS 430 flight management system, Garmin said.

"That Garmin equipment is currently only approved on the Eurocopter AS350 series of aircraft," said Elvis Moniz, avionics director with AcroHelipro, Richmond, British Columbia, Canada.

AcroHelipro performed ADS-B and glass-cockpit upgrades on the AS350 helicopter for the Alaska Capstone program trials.

"The Gulf of Mexico initiative will undoubtedly require a variant of this, but it is unknown at this time what the equipment requirement will be in the Gulf," Moniz added.

AcroHelipro has its main avionics facilities in Langley, B.C., and in Andalusia, Ala. It can also send technicians to the operator’s facility to perform the upgrades there, Moniz said.

A ballpark estimate for the equipment is "about $10,000," while total installation and equipment costs would be in the $14,000 to $15,000 range. The down time is about four days.

Currently, there is a lead time for the work of about two weeks, although that will probably change once "everyone starts getting their installations done," Moniz said.

Fontenot noted, however, that the Capstone program was funded by the government and used as a test basis for ADS-B. The avionics components required to bring ADS-B capability to Gulf helicopters are not government funded. "So I don’t see [Gulf] operators going with the Capstone model," Fontenot said.

Another question remains over the degree of capability that will be required of Gulf helicopters equipped for ADS-B.

"The operators are going to put in whatever equipment is required for the FAA to see us once the ADS-B portion is installed," Fontenot said.

"It’s going to take a long time for all the equipment to be there and all the services to be available. So why would an operator want to go out and buy a new add-on box now, then in three or four years have to buy another box? I see the operators just doing whatever is required to have Houston Center see us, whatever that level is."

ADS-B Vendors Step Forward

FAA received three responses — from Lockheed Martin, Raytheon and ITT Corp. — to its recent Screening Information Request to provide ADS-B services.

At this writing, the agency determined that the three industry teams satisfied requirements to submit proposals.

The final selected vendor will provide ADS-B services to users across the National Airspace System.

FAA plans to issue a Notice of Proposed Rulemaking on Sept. 7 for the avionics portion of the program, according to Vincent Capezzuto, FAA program manager for ADS-B. This is being done under a dual-tracking approach that will link the ground infrastructure to the airborne avionics requirements.

"To bridge the two together, we have a development called separation standards approval through the safety office, so they can say, ‘Yes, you can separate aircraft using ADS-B,’" Capezzuto said.

ITT Corp., White Plains, N.Y., is teamed with AT&T, Thales, WSI, SAIC, PriceWaterhouseCoopers, Sunhillo Corp. and Aerospace Engineering in pursuit of the ADS-B contract.

"We’re very pleased to be selected to compete for the opportunity to partner with the FAA in this critical endeavor to make air travel more seamless," said John Kefaliotis, ITT’s ADS-B team leader.

"We look forward to working with our teammates to continue ITT’s 60-year legacy of innovation in air traffic control technology."

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