More Details Emerge Regarding ITT Team's ADS-B Win

It seems apparent that the FAA's decision to award the team led by ITT with the contract to implement a nationwide U.S. ADS-B (automatic dependent surveillance-broadcast) system was affected largely by its use of AT&T's existing network, as well as a novel contractual paradigm.

As first reported by Aviation Daily, ITT's proposal called for ADS-B ground equipment to be installed on AT&T's in-place cell-phone towers and other installations, and the use of AT&T's existing telecommunications operations centers, all of which are considered "highly reliable and secure," according to John Kefaliotis, ITT's director of business development for FAA and ATC programs.

AT&T also will provide its MPLS (multiprotocol labeled switching network) to transmit ADS-B data between ground elements of the system. These, too, are considered highly reliable as well as redundant.  There will be 794 ground radio stations when the ADS-B system is fully deployed, and a significant number of these will be installed in existing AT&T telecommunications towers.

In addition, data will be processed in some of AT&T's existing data hosting and processing centers. The ITT ADS-B system will aim to have four data hosting centers nationwide by the time it is fully rolled out, and they will also "leverage network operation centers for overall monitoring of system performance," Kefaliotis said.

Performance-Based Contract

ITT's proposal appeared to be in line with the FAA's new "performance-based" procurement practice, where the single essential requirement is to provide a continuous ADS-B service that meets the agency's performance specifications.

The rationale for such an approach is to reduce the need to add to the agency's capital budget and free ITT from some of the onerous, and many believe unnecessary manufacturing criteria, which have been common in previous large system procurements.  In other words ITT will be responsible for the quality and availability of the uplinked signals and data, but will not be told how to provide them.

The contract breaks some new ground in other ways too, in that the FAA will pay ITT for using the system, not for building the system, which has been the traditional way.  Without overly emphasizing this shift, it's nevertheless an important change, and seems to reduce some of the government's risk.

When compared to the proposals of Raytheon and Lockheed Martin, the ITT bid "combined the best value and the least risk," Deputy FAA Administrator Robert Sturgell told reporters in a teleconference.

Technical Details

ITT proposed a dual-frequency approach to the ADS-B architecture that will involve the use of UAT (universal access transceivers) on GA (general aviation) aircraft and 1090ES (extended squitter) transponders on airliners and other larger airplanes, such as business jets.

UAT in the U.S. is meant to not only broadcast ADS-B data from equipped aircraft, but also to receive traffic information services (TIS-B) about other nearby airplanes and broadcast flight information services (FIS-B) such as weather.

The limited bandwidth of 1090ES, however, prevents the reception of large messages, such as weather information, which will likely require unique solutions for some operators. These could include small, standalone, airline-qualified UAT packages, which could offer a full range of ADS-B benefits, including FIS-B. Other operators might rely on new broadband datalinks to deliver such information from their own or third-party sources and display the information on devices such as EFBs (electronic flight bags).

Industry could likely develop ADS-B "in" messages similar to TIS-B for large airline-type aircraft too. UPS is already using Aviation Communications and Surveillance Systems (ACSS), TCAS and Mode S units to provide both "out" and "in" ADS-S messages.  ACSS is a member of the ITT team.

Implementation Schedule

For the first three years of the contract, the ITT team will develop and deploy the system in the Gulf of Mexico, Louisville, Philadelphia and Alaska, gearing up to an eventual full deployment of ADS-B nationwide by 2013.

In six years, ADS-B "will be available everywhere we have radar," Mr. Sturgell predicted.  09-11-2007.

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