On May 22, 2020, The Aerospace Industries Association, The Aircraft Owners And Pilots Association, Airlines For America, Aviation Spectrum Resources, Inc., The Cargo Airline Association, The General Aviation Manufacturers Association, The Helicopter Association International, The International Air Transport Association, The National Air Transportation Association, and The National Business Aviation Association filed a Petition for Reconsideration of the FCC’s Ligado Decision.
They argue:
“The Commission’s Order and Authorization (“Order”), which grants Ligado’s license modification applications, recognizes that GPS receivers and SATCOM terminals are entitled to protection from interference caused by Ligado. The record in this proceeding does not substantially support the decisions the Commission made. As a result, the Order does not impose technical and operational parameters that will deliver appropriate protection to GPS and SATCOM. In an attempt to make up for this failing, the Order adopts a long list of license conditions. But these have numerous deficiencies and arbitrarily shift much of the burden for protection upon the aviation industry itself, putting air safety and aviation operations at risk. For these reasons, the Order should be reconsidered and the Ligado applications denied.
- For its decision on how to protect Federal Aviation Administration (“FAA”) certified aviation GPS receivers, the Order relies heavily on an FAA analysis of the potential for Ligado to cause harmful interference to certified safety-of-life GPS receivers at the boundary of a 250-foot radius cylinder around Ligado base stations, and a boundary 30 feet above those stations (the “250/30 Cylinder”). But that analysis, by the FAA’s own recognition, did not conduct a full assessment of operational considerations within the 250/30 Cylinders or among a dense deployment of Ligado base stations such as low-altitude operations of helicopters and Unmanned Aircraft Systems (“UAS”). Nonetheless, the Order inexplicably relies on that very analysis (without supplementation), and a mischaracterization of an FAA rule, to find that all operational scenarios concerning certified receivers have been addressed. In so doing, the Order ignores the large body of evidence the aviation community provided showing that FAA-certified GPS devices would be regularly used in close proximity to Ligado base stations. As a consequence, the technical and operational parameters adopted by the Order applicable to Ligado’s base station operations in 1526-1536 MHz do not protect aviation’s use of certified receivers near Ligado base stations.
- The Order’s conditions do not make up for the flaws of this insufficient technical analysis. The notification provisions require Ligado to establish a database for pilots’ use outside the normal FAA processes on which pilots rely for information about obstacles. This directive is seriously vague and raises numerous significant questions. This new notification mechanism is also beyond the Commission’s authority to adopt. The interference complaint condition places too much authority and discretion in the hands of Ligado offering little certainty that interference situations will be adequately and timely addressed. The Order also makes unfounded assumptions about how UAS currently and in the future will use GPS for operations in low-altitude environments, putting at risk new growth industries.
- With regard to non-certified receivers, the Order discounted the interference assessment standard based on a 1 dB change in the carrier signal-to-noise ratio that has been supported consistently by the relevant federal agencies, the major GPS manufacturers, and the aviation industry and which the record evidence showed is the best objective predictor of interference to GPS devices. Exacerbating the error of this rejection, the Order relied on Ligado-sponsored studies that are insufficiently narrow. For example, these studies looked at only two of many important functions performed by non-certified GPS receivers on which critical aviation systems rely. In addition, the studies only looked at a single non-certified GPS receiver used by aviation and did so in a non-aeronautical test set-up. And again, the conditions imposed by the Order in an attempt to make up for the expected interference from Ligado are insufficient to shore up the other deficiencies of the Order which fail to protect noncertified receivers.
- Finally, the Order recognizes the need for measures to protect SATCOM from interference caused by Ligado. But the Order unjustifiably relies upon resolution of long-open negotiations between Ligado and Inmarsat – which have occurred without aviation industry involvement – to develop terms for a major retrofit of aircraft using Inmarsat SATCOM. Regarding potential interference to Iridium SATCOM, the Order’s encouragement of Ligado and Iridium to keep talking hardly passes for sound spectrum management and a similarly flawed response to demonstrated interference concerns. The Order’s inadequate treatment of the SATCOM issues amounts to the Commission adopting no protective measures whatsoever.