There have been hundreds if not thousands of articles written about ADS-B Out and the Federal Aviation Administration’s 2020 mandate. In addition, there’s been a few hundred presentations given stating that close to 150,000 aircraft will need ADS-B Out installations before Jan. 1, 2020, and the available resources to support the procrastinators will be challenged at best. We know people procrastinate; it’s human nature, and why spend the money three years before the equipment is actually required?
As a result, we know 2018 and 2019 will be extremely busy years and anyone with a toolbox will be asked to install a “simple” ADS-B Out transmitter. But the system is not simple, and should you do it? And if you do, what are the requirements?
In full disclosure, my employer, the Aircraft Electronics Association (AEA) is a trade organization that represents more than 1,200 aviation businesses worldwide, including the repair stations that specialize in maintenance, repair and installation of avionics and electronic systems in general aviation aircraft. I am an A&P with more than 40 years of aircraft maintenance experience. I also have spent the last half of my career on the quality and compliance side of the industry, so I will focus on the compliance side of meeting the ADS-B Out installations.
What is NextGen?
According to the FAA, “NextGen is the transformation of how airplanes traverse the sky. It affects all of us: from the pilots who fly the planes, the passengers who enjoy the flights and the controllers who ensure the safety.” NextGen is essentially the modernization of both Air Traffic Management and the systems in the aircraft needed to support and benefit from this modernization of the ground infrastructure. NextGen includes the modernization of each of the three elements of avionics: communications, navigation, and surveillance. ADS-B Out is the modernization of surveillance.
While we are seeing advancements in communication and navigation technologies as well as the improved efficiencies of digital communications and precision navigation, there are no current regulatory mandates. There is, however, an expanded use by the agency to leverage a philosophy known as “best equipped – best served.” Internationally, there are transoceanic mandates required by the International Civil Aviation Organization (ICAO) as well as a variety of international mandates implemented by individual countries.
This article focuses on the surveillance piece, the ADS-B Out mandate and the required installations. As we know, 14 CFR 91.225 Automatic Dependent Surveillance-Broadcast Out equipment and use mandates that if we fly in “rule” airspace, we must have an approved ADS-B Out system installed and we must use it. I won’t go into the details of 14 CFR 91.225 and 91.227, but if your customer is flying in airspace that currently requires a transponder, then that airspace will likely require an ADS-B Out system. Remember, this is the modernization of surveillance, so it is logical that if they are required to be under positive surveillance today, they will likely be under positive surveillance tomorrow.
Calculating from March 1, 2017, until the final date for completion in order to meet the midnight, Jan. 1, 2020, deadline, there are only 713 working days, excluding weekends and holidays. That is not a lot of time and certainly doesn’t allow the procrastinators to procrastinate very long.
Technician qualifications: Let’s look at the age-old question. Can an A&P mechanic install radios? Yes, of course – sort of!
As far as avionics work goes, 14 CFR 65.81 (a) the general privileges and limitations for mechanics, authorizes a certificated mechanic to perform or supervise the alteration of an aircraft for which he is rated but excluding any repair to, or alteration of, instruments. So the installation of a radio is well within the scope and authority of an airframe-rated mechanic.
However, the mechanic may not supervise or approve and return to service the alteration unless he has satisfactorily performed the work concerned at an earlier date. The language of 14 CFR 65.81 (a), which is often overlooked, requires the mechanic to be experienced with the task they are performing in order to have return to service authority. In the case of ADS-B Out systems, this is not a simple installation of a transmitter but rather an installation along with integrations and configuration. So in order to satisfy 14 CFR 65.81 (a), the mechanic would need to show experience with similar integrated, configurable types of installations. The regulations go on to lay out a plan for qualifications if they have performed the work at an earlier date.
Assuming the technician is qualified to do ADS-B installations, what are the qualifications of the systems?
14 CFR 91.225 requires either ADS-B Out equipment that meets the performance of Technical Standard Order (TSO)-C166b, Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B) Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz), or TSO-C154c, Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz. While the regulation clearly states “meets the performance requirements,” there are other regulatory cites that effectively require “approved equipment” in certified aircraft, so you want to be looking for either TSO-C166b or TSO-C154c.
ADS-B Out equipment for EAB/LSA must meet the “performance” requirements of TSO-C166b; or TSO-C154c. The FAA does not “approve” pairings for EAB/LSA, so the manufacturer must attest to the appropriate performance levels for these aircraft.
Is the installation of ADS-B Out a major or minor alteration?
The FAA March 2, 2016, memorandum titled, “Installation Approval for ADS-B Out Systems,” contains three critical elements: (1) blanket (FAA HQ issued) follow-on Field Approval of previously approved STCs; with (2) the approval of the STC holder; but (3) you must treat all follow-on installations as if they were major alterations.
Therefore, based on the administrator’s policy, all ADS-B Out installations must be treated as (at a minimum) a major alteration. According to FAA Advisory Circular (AC) 20-165B, the initial airworthiness approval of all ADS-B Out “systems” is done via a type certificate or a supplemental type certificate. However, follow-on installations of the TC/STC are allowed.
The March 2, 2016, memorandum contains specific language and procedures allowing a follow-on installation of a TC/STC approved pairing (system) without an explicit FAA Form 337 block 3 signature. However, there are specific procedures and limitations that MUST be followed. This would be extremely important to every A&P with an Inspection Authorization before they signed the conformity in block 7.
Contained within the memorandum is a note about 14 CFR 91.403 (d), which states: “A person must not alter an aircraft based on a supplemental type certificate unless the owner or operator of the aircraft is the holder of the supplemental type certificate, or has written permission from the holder.” As a result, in order to take advantage of the FAA headquarters authority for a follow-on field approval for ADS-B Out installations, the installer must be authorized by the STC holder to use the installation data.
What are the technician’s performance rules?
The regulation (14 CFR 43.13 (a)) requires that each person performing an alteration to “use the methods, techniques, and practices prescribed in the current manufacturer's maintenance manual or Instructions for Continued Airworthiness prepared by its manufacturer, or other methods, techniques, and practices acceptable to the administrator.” Since there is no “acceptable” data available for ADS-B Out installations and since the FAA requires ADS-B Out installations to be treated as if they are major alterations, the installer must use approved data.
The regulations continue with a requirement to “use the tools, equipment, and test apparatus necessary to assure completion of the work in accordance with accepted industry practices. If special equipment or test apparatus is recommended by the manufacturer involved, he must use that equipment or apparatus or its equivalent acceptable to the administrator.” Every installation manual requires special test equipment to verify the proper configuration of the ADS-B Out system before return to service.
Currently there are some 20,000 systems installed with a wholly unacceptable error rate of nearly 20 percent. What are the common installation issues?
The seven most common errors are mostly in the configuration of the installations. They include errors in:
• Emitter Category
• Air/Ground Determination Issues
• Baro/Geo Altitude Spikes
• Missing Baro Altitude
• Duplicate or Wrong ICAOs
• Invalid/Missing Mode 3/A Codes
• Flight ID issues
To resolve these installation errors, anyone installing ADS-B Out must familiarize themselves with AC 20-165B Airworthiness Approval of Automatic Dependent Surveillance-Broadcast Out Systems. Many people get confused because the stated purpose of the AC is to “provide guidance for the initial installation and airworthiness approval of Automatic Dependent Surveillance-Broadcast (ADS-B) Out equipment in aircraft.” Since most installations are follow-on installation of some type, they dismiss the AC as not applicable.
AC 20-165B Chapter 3 contains ADS-B Out system installation guidance, while paragraph 3.2.3 provides guidance on specific configuration of the associated parameters.
The final issue surrounding ADS-B Out system installations is that TSO-C166b systems are also a Mode S transponder, which will require retesting of the transponder under § 91.413.
§ 91.413 (b) states that “Following any installation or maintenance on an ATC transponder where data correspondence error could be introduced, the integrated system has been tested, inspected, and found to comply with paragraph (c), appendix E, of part 43 of this chapter.”
So going back to the leading question: Can an A&P mechanic install radios? Yes, but the other regulations in Part 43, 65, and 91 require attention. ADS-B Out is not simply a radio with a couple of wires, it is an integrated system that requires installation, integration, and configuration.
Ric Peri is AEA vice president of government and industry affairs. Peri is an A&P with more than 40 years of aircraft maintenance experience. He can be reached at [email protected] or (202) 589-1144. The 60th annual AEA International Convention & Trade Show will be held March 13th to the 16th in New Orleans, Louisiana. For more information visit www.aea.net.
