Thousands of Aircraft to be Grounded as ADS-B: DEADLINE LOOMS By Kathryn B. Creedy

Thousands of Aircraft to be Grounded as ADS-B: DEADLINE LOOMS By Kathryn B. Creedy

One month out from the January 1, 2020 deadline requiring all aircraft operating in U. S. skies to be equipped for Automatic Dependent Surveillance-Broadcast (ADS-B), it is clear thousands of aircraft in the US will be grounded.

While the vast majority of ADS-B equipped aircraft transmit accurately, thousands of aircraft have what the FAA calls Non-Performing Emitters (NPEs), meaning they do not transmit their position accurately. FAA chart.
While the vast majority of ADS-B equipped aircraft transmit accurately, thousands of aircraft have what the FAA calls Non-Performing Emitters (NPEs), meaning they do not transmit their position accurately. FAA chart.

The gap between equipped and unequipped aircraft has narrowed steadily this year but now comes at a time when MROs are historically very busy. The equipage rate is complicated by the fact about 8,000 equipped aircraft are not transmitting properly, according to the Federal Aviation Administration (FAA).

This comes as the last of 20,000 $500 FAA rebates, designed to mitigate the costs of equipping general aviation aircraft, was claimed on October 11, according to the agency, ending the three-year-old program. However, those who have received such a rebate but who have not equipped can still take advantage of the program.

At the same time, the FAA completed the final implementation milestone for ADS-B when it became operational at the last two – Akron-Canton and Mansfield, OH – of 155 airports to receive ADS-B, bringing the operational rollout of baseline services to a successful conclusion on schedule and within budget. ADS-B is now operational at air traffic control facilities including airports, Terminal Radar Approach Control Facilities, which handle busy airspace around airports, and en route facilities, which handle high altitude traffic improving situational awareness to both pilots and controllers.

By the Numbers

Accurate numbers of equipped aircraft, however, are hard to come by owing to the different dates on the reports and other factors so turning to the Federal Aviation Administration (FAA) for insight seems a prudent choice. However, some doubt the accuracy of even those figures. What we do know is, at the end of 2018, there were 212,875 general aviation aircraft, according to the FAA’s 2019 Forecast, while only 105,355 aircraft in the civil fleet have been equipped. The forecast, however, does not include the number of commercial aircraft but the agency’s online ADS-B equipage site notes 6,359 aircraft are in the commercial fleet but seems to indicate not all are equipped.

The most recent statistics show 2,277 international carrier aircraft have been equipped and only 51 are NPEs. FAA chart
FAA chart.
FAA chart.
FAA chart.
FAA chart. 
Duncan’s ADS-B website shows 26% of business jets remain unequipped.
Duncan’s ADS-B website shows 26% of business jets remain unequipped.

In a June report to Congress, the Department of Transportation Inspector General reported 3,849 (81%) of the 4,763 aircraft at the 11 mainline passenger and cargo airlines were equipped.

FlightAware reported October equipage rates were inching higher with 85% of registered turbine-powered business aircraft (15,077) equipped, a dramatic increase from the 62% equipped a year earlier. For business aircraft the highest equipage rates reflect more recent deliveries such as the Cirrus Vision SF50 at 99%, HondaJet (98%), Cessna Citation (96%) and Embraer Legacy 450, (95%).

“In addition to receiving over 45 different government air traffic control and private datalink sources, FlightAware operates a worldwide network of ADS-B and Mode S receivers that track ADS-B or Mode S equipped aircraft flying around the globe,” according to its website. “ADS-B equipped aircraft emit their exact position and Mode S aircraft can be tracked via multilateration (MLAT) when the signal is received by three or more receivers. FlightAware owns and operates these receivers at hundreds of airports around the world in conjunction with airport operators.”

The lowest equipage rates, according to the report which indicated 2,627 U. S.-registered turbine aircraft remain unequipped, include Dassault Falcon 20 at 65%, Citation III (66%), Learjet 55 and Quest Kodiak at 67% and IAI Astra (69%). Duncan Aviation, however, estimates 6,000 business jets remain unequipped as of November 9, 2019.

Duncan Aviation’s Satellite Operations Manager Matt Nelson said FlightAware numbers may be misleading because it is just turbojets.

“If you look at the turboprop market, compliance is only in the 60s and GA and helicopters are lower than that,” he told Aerospace Tech Review. “This could most definitely be a forward indicator of the number of aircraft destined for retirement, especially for the commercial fleet. Anything not in the process of being fitted now are probably scheduled for the boneyard.”

MROs Booking Into the New Year

As to what this means for MROs, Nelson thinks the situation is complicated by a head-in-sand approach by many operators.

“If the floodgates opened and the remaining turbojets came in between now and the end of the first quarter of 2020, we could get it done but that’s probably not going to happen because about one third will be parted out,” he said. “But that still leaves two thirds and that is a couple of thousand aircraft. I think you’ll see an uptick in equipage between now and the end of the year but there is still a certain part of the population that is just not paying attention.”

Duncan, and many other MROs, have been very pro-active in reaching out to operators and clients and getting their ADS-B plans on the record to cover themselves when operators try to blame them for not being equipped.

“We still hear excuses on why someone is not equipping like they are going to sell the aircraft,” he said. “Or they think the feds will fold and provide an extension at the last minute. All I can say is, with all the preparation, the outreach and the publicity, good luck with that. We’ll do the best we can, and we do have capacity in certain places, but people need to start acting.”

The other problem, he suggested, is operators thinking they can incorporate their equipage as part of their already-scheduled inspection. “It’s highly likely they will be told that it can’t be done during the inspection,” said Nelson. “But we are eventually going to run out of capacity and time.”

Privacy Hurdle Overcome

While some may think that is a forward indicator of retiring aircraft, it may not be. The FAA in November developed a method to ensure privacy of aircraft owners/operators, something long sought by Aircraft Owners and Pilots Association (AOPA) and the National Business Aircraft Association (NBAA) afraid that, without such measures, government and business leaders would be subject to security risks such as corporate espionage, extortion or terrorism. See sidebar page 30.

The lack of privacy was a powerful disincentive to equip, said NBAA President Ed Bolen when FAA announced its plan to allow a real-time, flight-tracking, opt-out for operators that have equipped their aircraft with ADS-B. The agency, which has developed a dedicated website for the program, has established new terms of service agreements with aircraft tracking service providers, effective before year’s end in a two-phase roll out, that will limit aircraft data sharing if operators opt out of having their flight information broadcast over the Internet (see sidebar).

The privacy program is one of the final pieces to fall into place as the industry turns on final approach to the deadline.

Duncan Aviation said in October it is now booking equipage work well into March 2020 which likely mirrors the capacity for most MROs. Installation could be, according to Nelson, as little as a week to a week and a half costing from $2,000 to $200,000 depending on how fancy the equipment is and what needs to be done.

Transmitting in Compliance

Duncan, which has been extremely active in equipping aircraft, urged owner/operators that upgraded to ADS-B in 2014 or 2015 to ensure their aircraft are transmitting in compliance, citing FAA’s finding 8,000 aircraft had non-performing emitters (NPEs) meaning their signals regarding position, speed, location in relation to other aircraft and other information to ATC may be inaccurate.

Disturbingly, as equipage increases, so, too, does the number of aircraft with NPEs. The FAA reported on November 1 that of the 105,355 equipped aircraft in the civil fleet, more than 8,000 have NPEs.

On September 30, after FAA notified Delta its A350-900s failed to meet accuracy requirements during surface movements, the airline requested a two-year exemption from the ADS-B performance requirements, until the anomaly can be fixed.

One reason for any noncompliance of ADS-B transmitters, according to Duncan Aviation Manager of Completions & Modification Services Sales Nate Klenke, is an incorrect software version or improper configuration both of which reduce the accuracy of aircraft position. Another could be an incorrect emitter category which happens when the ADS-B system transmits the wrong maximum take-off weight. Duncan also cited an incorrect flight ID when the aircraft’s registration for Mode S doesn’t match the ID. Finally, it said an error could occur when the aircraft is on the ground as in Delta’s case.

“Many of the aircraft with NPEs were likely installed more than four years ago or prior to changes made in the mandate and implemented over the years after its initial announcement,” he said. “Some, however, may be a result of an improper installation or equipment configuration.”

The company advised testing compliance by requesting a Public ADS-B Performance Report (PAPR) from the FAA, used to verify equipment is functioning properly. If the system fails, the report will tell operators what parameters have failed and what needs correction.

Limiting Aircraft Data Displayed (LADD)

Aircraft owners can request limiting aircraft data displayed, referred to as blocking, or unblocking of flight tracking data. Limiting aircraft data from the FAA data systems will limit flight tracking information transmitted over the Internet. “Unblocking” will ensure aircraft flight data will be included in the FAA data feed utilized by internet flight tracking vendors, according to FAA.

To file a request for limiting flight data options, there are two options are available:

1. FAA Source: With the FAA source option, your aircraft data is limited to FAA use only. No FAA flight data will be available to external vendors. If you are considering limiting data at FAA Source, FAA flight data on your aircraft will not be available to internet web sites.

2. Subscriber Level: With this option, flight tracking data is made available from the FAA data feeds to vendors (i.e. internet flight tracking vendors). However, vendors are bound by access agreement to not publicly display information for aircraft on the subscriber level blocked list. This option allows aircraft owners or operators to track or monitor aircraft through an internet flight tracking provider.

To track an aircraft, the aircraft owner or operator must contact the flight-tracking provider and request flight tracking information be selectively available.

If you want to unblock your FAA flight data, another request to remove any data limits previously requested is required. This request will remove aircraft data limiting. Your flight tracking data will resume being transmitted to vendors who receive FAA data feeds.

The FAA says they implement limiting aircraft data displayed on the first Thursday of each month and that requests they receive on or before the 15th of the preceding month are likely to be processed in time to take effect in the month following receipt. There are three ways to submit your request: using the easy-to-use form, via email, or via postal mail. The following information must be included in your email request:

  • Aircraft Registered Owner(s)
  • Aircraft Registration Number or Call Sign of the aircraft data to be limited or unblocked
  • E-mail Address to which the FAA can direct questions about the request
  • ICAO Code
  • Telephone number to which the Federal Aviation Administration (FAA) can direct questions about the request
  • Aircraft Make and Model
  • Desired level of limiting data (FAA Source , Subscriber, or Unblocking)
  • Certification that the requestor is the owner or operator of the specified aircraft, or is a legally authorized representative of the aircraft owner or operator.

“The FAA has a performance monitoring system and they are capturing the data on what aircraft have a problem,” explains Kerry Crawford, Viavi products manager, Avionics Test, whose company supplies test equipment as well as ways to mask the aircraft during ground testing which is a further problem being encountered. “Those aircraft with problems have to go back to the shop to be tested to resolve the issues. FAA sends a report to operators to alert them of a problem and what is wrong with the signal.”

FAA chart.
FAA chart.

Crawford explained the problem. “Technicians have to ensure they are not interfering with ATC or other aircraft which naturally assume the test aircraft is at altitude,” he told Aerospace Tech Review. “This is a problem since systems such as TCAS would ‘see’ an aircraft that is not actually there, conclude there is a conflict and provide an alert and a resolution advisory when there is no conflict at all. When an MRO is testing the aircraft and bringing it to altitude, it is squitering out as if it is at that altitude when it is actually on the ground, The FAA issued a SAFO on this to tell maintenance personnel to ensure they use an antenna coupler or notify ATC when they are testing.”

Viavi TC-201A TCAS/Transponder Antenna Coupler. The Viavi TC-201A Antenna Coupler is used on TCAS and combined TCAS and transponder directional antennas, to shield the RF signal during testing of the TCAS or transponder system. The TC-201A supports maintenance testing in the airborne condition without interfering with air traffic control or nearby aircraft.

Viavi’s TC-201A TCAS/Transponder Antenna Coupler
Viavi’s TC-201A TCAS/Transponder Antenna Coupler

Much work remains to be done to fully equip the U. S. fleet and ensure it is transmitting accurately but the vast majority of aircraft in the civil fleet are already there. Permissions to operate without ADS-B will be done on a complex case-by-case basis, accord to the FAA and mostly designed to reposition aircraft for ADS-B installation center.

Those with their head in the sand, will get a rude surprise come January 2 when they cannot take off, nor can they find the capacity needed to equip their aircraft in a timely manner. Observers expect that reality, coupled with higher maintenance costs for older equipment, will determine the fate of this fleet.