By Toby McIntosh
The US Federal Aviation Agency is creating a new system to preserve the option for aircraft owners to fly anonymously.
Although an existing “blocking” system permits anonymity, that ability has been disrupted by a new tracking technology, Automatic Dependent Surveillance—Broadcast (ADS–B). Use of ADS-B by the end of 2019 is required in the US and adoption internationally is under way.
With ADS-B, aircraft signals can be received by anyone with about $100 worth of equipment. The transmissions include codes identifying individual planes. Thousands of persons with receivers, mainly amateur aviation enthusiasts, send the signals to the comercial vendors who provide flight tracking information. The ADS-B data is combined, permitting detailed maps of aircraft movements.
Before ADS-B, flight tracking services relied mainly on data from the FAA. US aircraft owners are permitted to ask the FAA for their aircraft to not to be identified publicly. Vendors who receive FAA air traffic data can see the blocked information, but as a condition of access, may not distribute it to the public.
The status quo has been upended by the ADS-B transmissions. One online database company in particular, ADS-B Exchange, based in Arizona, began identifying planes regardless of whether they were enrolled in the FAA blocking program.
Because ADSB Exchange does not rely on FAA tracking data, it is not obligated to honor plane owners’ requests for anonymity made under the government blocking system. Other major tracking vendors, such as Flight Aware and FlightRadar24 honor the blocking requests made through the FAA system.
New System Being Planned
To counteract the new visibility enabled by ADS-B, the FAA is developing a system that will continue to permit anonymous flight for those requesting it.
The FAA plans to assign temporary identification numbers, known as “rolling ICAO codes,” to owners who ask for them.
At present, a specific ICAO code is assigned to each aircraft, drawn from a batch of numbers given to governments by the International Civil Aviation Organization. The codes, transmitted via ADS-B, can be used to identify owners through the US aircraft registry, which is public.
With a temporary ICAO code, an aircraft could still be tracked via ADS-B, but could not be linked to its owner through the registry. As a result, its ownership would be unidentifiable except to air traffic controllers and other authorities.
Details of Program Under Development
While the goal is clear, public details on the rolling ICAO code system are scarce at this stage.
The FAA explained March 25, in reply to EYE questions, that “the concept under development by the FAA involves partitioning a pool of 24-bit ICAO addresses in the U.S. allocation and authorizing them for random use by operators desiring improved privacy.” The statement continued, “These addresses would not be associated with a specific aircraft in the [registry].” The FAA said that “eligible aircraft would have to be flying in U.S. airspace.”
The FAA is working with industry on developing the rolling ICAO code system.
Industry representatives are expecting to hear more about it at a meeting March 27 of an advisory group, EQUIP 2020, that for several years has been discussing dozens of issues around with ADS-B implementation. The use of ADS-B by the end of 2019 has been mandated in the US. The meeting is not open to the public.
The FAA in March 2018 “Market Survey” invited “interested vendors” to propose “approaches” that would “improve real-time privacy of aircraft.”
The agency this week said it “is working with internal stakeholders to incorporate feedback from respondents and finalize requirements. No specific implementation decision or timeline has been determined.”
The seven-paragraph Market Survey said “key evaluation criteria … may include validation capability, performance monitoring and controls, past performance in support of operators’ privacy, and a business model that is most favorable to the FAA.”
Behind Schedule
“Further, the FAA’s intention is to have a fielded service by December 2018 and seeks partnerships supporting that schedule,” according to the document.
The effort is behind schedule, sources told EYE, partially affected by the early-2019 government shutdown.
“Once the FAA awards the contract to the vendor(s), testing will be planned and conducted,” the FAA told EYE. It stated:
The FAA plans to enter into an agreement with one or more third-party service providers that will develop, test and implement a system to manage the pool of additional ICAO addresses and monitor their use. The ADS-B Performance Monitor will correlate the use of any additional ICAO addresses to the appropriate aircraft to ensure the accuracy and completeness of performance data.
No Rulemaking Necessary, FAA Says
The FAA said that no rulemaking procedures will be required to implement the “rolling” system. With rulemaking, proposed rules are drafted and public comments invited.
The agency told EYE that “… use of a rolling ICAO code would be purely optional, so the FAA does not plan on going through any rulemaking processes for rolling ICAO codes.”
The existing system through which owners can request anonymity was the subject of a rulemaking process, however. (See Federal Register notice from Aug. 21, 2013.)
Under the FAA program, known as Aircraft Situation Display to Industry (ASDI), owners can request that their aircraft not be identified publicly, a process that takes several weeks. Those who receive FAA air traffic data feed can see the blocked information, but must sign an agreement pledging not distribute the information except with the owner.
FAA and industry officials say only a fraction of private aircraft owners avail themselves of the ASDI system, but no precise statistics were available.
The blocking program is grounded in a 2011 appropriations bill (HR 2112) rider prohibiting funds to be used “to implement or to continue to implement any limitation on the ability of any owner or operator of a private aircraft to obtain, upon a request to the Administrator of the [FAA], a blocking of that owner’s or operator’s aircraft registration number from any display of the [FAA’s ASDI and NASSI] data that is made available to the public, except data made available to a Government agency, for the noncommercial flights of that owner or operator.”
Business Advocates Continuing Anonymity Option
Approval of a successor anonymity system in the US may not be without controversy although several groups that might be critical said they were unaware of the development.
But aviation industry groups, such as the National Business Aviation Association, have advocated for a new confidentiality system, saying it is necessary for safety and security reasons. In addition, industry officials noted that executives dislike that those tracking their movements might figure out upcoming business deals. Several consulting companies specialize in such analysis.
Planes, one official said, should be treated like motor vehicles, whose owners can’t be ascertained by the public from their license plates. Transparency advocates prefer the model of maritime shipping, where tracking identifies ships by name (although figuring out actual ownership can be difficult.) Identifying plane owners also can be complicated. In the US, ownership can be masked through the use of trusts. US law permits foreigner owners to transfer title to a US trustee.
Wider Implications
Whatever technical and programmatic adjustments are adopted by the US could have international implications if the rolling code system were to be adopted elsewhere.
However, most countries do not disclose ownership information, thus making it very difficult to identify owners even with ADS-D signals. Countries with open registries have not adopted systems like the US blocking option.
ADS-B adoption worldwide has been encouraged by ICAO and is steadily occurring. The European deadline is mid-2020.
