PBCS Monitoring Requirements

Why did the FAA Choose March 2018 For a PBCS Deadline?

The ICAO Provisions for Performance Based Communication and Surveillance, PBCS including new Standards and Recommended Practices (SARPS) and related guidance material have been applicable since 10 NOV16. It became apparent to the NAT Systems and Planning Group and Asia/Pacific Air Navigation Planning and Implementation Regional Group that worldwide PBCS would not be fully implemented by that date. A new date was agreed upon, 29MAR18.

Why do I have to do this PBCS Monitoring Stuff?

ICAO has set the standard for existing and planned RNAV and RNP based 50 NM and 30NM longitudinal and 30NM lateral separation minima should continue, subject to the conditions that:

  •           PBCS monitoring is in place; and
  •           Performance-based horizontal separation using PBCS designators in flight plans is implemented as soon as practically possible.

 

Some States may require the filing of PBCS designators in flight plans for the provision of 50 NM and 30 NM longitudinal and 23 NM (formerly 30 NM) lateral separation minima after the applicability date of the PBCS provisions.

For Current OpsSpec/LOA A056 holders, after 29MAR18 and w/o PBCS monitoring data, does the OpsSpec/LOA become invalid?

Yes, is the short answer. Current A056 holders will have to comply with a mandatory change to the new A056 template.  With the new template, the operator will have to determine if their aircraft is eligible for RCP/RSP (PBCS) operations.  This is done by following Chapter 3 of AC 90-117 (replacing AC 120-70C and soon to be published). An FAA operator’s guide to compliance is also in the works, (to be published after the AC).  ICAO has already published new guidance in Annex 11 and Documents #4444, #9869, and #10037.

Where is it that I can get this “PBCS Monitoring Data” ?

Since 2009 the FAA has tracked the rates of equipage, connection and continuity for CPDLC and ADS-C. FAA Washington has produced a monitoring webpage (similar to RVSM monitoring results) to publish this data. Here is a link: https://www.faa.gov/air_traffic/separation_standards/pbcs_monitoring/

During initial implementation, monitoring results will be posted every 6 months.  As the program matures, that interval may change. The period covered on this first published spreadsheet is JUL thru DEC 2016. The data on this spreadsheet comes from CPDLC and ADS-C connections pilots made in Oakland, Anchorage, New York OCAs. CPDLC/ADS-C connection and continuity data is being shared with the FAA from Reykjavik, Shanwick, Santa Maria, and Auckland OCAs. Gander chose not to contribute to the FAA’s database at this time but will provide their results on a case-by-case basis on request. Tokyo is still working through how they will manage the data sharing. Magadan and the others are an unknown at this point.

This required monitoring data will also need reports from your communication service provider on your CPDLC/ADS-C connection and continuity fail/success rates. It is not a requirement for OpsSpec/LOA A056 holders to keep PBCS monitoring data onboard while operating.

What is all this Data trying to Tell me?

Required Communication Performance, RCP the designator (i.e. RCP 240, 400) represents the value for the maximum communication transaction time after which the initiator should revert to an alternative communication procedure. Usually HF radio is the backup in oceanic/remote regions.

Besides a time threshold, an RCP specification represents operational values for communication transaction continuity, availability, and integrity applicable to the communication transaction supporting an ATM function. This elapsed time includes technical communication performance, average human-machine interface and average cockpit response times.

This is commonly referred to as “Cockpit thinking times”. “STBY” is not the response that triggers this timing threshold. Only the “ROGER” or “WILCO” count toward an RCP-240 qualification.

An RSP specification label (i.e. RSP 180, 400) represents the values assigned to RSP parameters for surveillance transaction time (in seconds), continuity, availability, and integrity. Traditionally, surveillance over oceanic and remote areas was limited to pilot position reports via High Frequency, HF radio. Once the aircraft entered a radar environment, pilot reports were eliminated.

Surveillance in oceanic and remote airspace is accomplished much more accurately through the use of ADS-C. As with CPDLC, ADS-C requires certain performance requirements for operational surveillance in support of specific ATM functions. This includes the transmission of aircraft position, velocity and intent with a specified precision, accuracy and update rates.

What Happens if I don’t pass the PBCS Test ?

The operator will have to provide proof of aircraft eligibility to either receive their initial authorization or add PBCS to their current A056 and monitoring data will be used to determine demonstrated performance.

All new A-056 approvals are to be initially approved with a provision to get monitoring and provide adequate sampling to remain qualified. 100 data points are the desired level of sampling. For “N”-registered aircraft, if it is found an operator/airframe does not have enough data, the initial authorization will be based on an OEM statement of compliance in the AFM, AFM supplement or similar documentation. 

One-off installations via STC's will be handled individually. Operators need to be diligent in getting problem reports to regional monitoring authorities. The next best option is to make your POI and the ATC agency involved aware of data link problems encountered.

If demonstrated performance monitoring is available and it is "pass", provide that information with their application.  If that monitoring data is "fail" that aircraft/fleet is not eligible for RCP/RSP (PBCS) ops pending satisfactory performance.  If no monitoring data is available or "insufficient data" is shown, the operator should include proof in their application and only the Statement of Compliance will be used.  Performance monitoring sight is listed in AC 90-117 Chapter 6.

Meanwhile, for further information on your specific airframe monitoring results, please contact Theresa Brewer, FAA Air Transportation System Evaluation Division, Separation Standards Analysis Branch, Office Phone: 609-485-5106, theresa.brewer@faa.gov

Just What Does all this Monitoring get me Operationally ?

RCP-240 is coupled with RSP-180 is the desired designation for ATC. These two designations are what allow ATC to separate your aircraft from other equally equipped and performing aircraft by minimum distances while preserving the Target Level of Safety (READ: no mid-air). Current reduced separation standards are 30NM lateral/longitudinal and 23NM lateral/5-min longitudinal.

The monitoring data for granting initial authorization will give an operator their OpsSpec/LOA A056 stating operational approval to use RCP/RSP at the performance level shown.  Subsequent monitoring data may "fail"; the operator should follow the guidance on the monitoring site.  They should not file the corresponding P-code/Block 18 code until they follow the given directions.  If performance doesn't improve, it may result in losing their A056 RCP/RSP authorization.  If this happens, the operator may still be able to participate in basic CPDLC/ADS-C ops.

Domestic USA enroute services are expected to begin in 2019 using existing FANS 1/A aircraft to deliver CPDLC services in the U.S. NAS en route airspace. 
Full enroute services are expected to begin in 2025 and will provide advanced services, such as four-dimensional (4D) trajectories, dynamic required navigation performance, advanced flight interval management with ATC wind information.

More Flight plan Equipment Codes

These documents will reference the use of "P-Codes" on the flight plan forms. P-1, 2, 3 or 4 when inserted into block#10 will indicate what level of RCP your CPDLC connections are operating at (400sec or 240sec).  Here is an example:

Item 10: Equipment, 10A Communication and Navigation (Before the diagonal mark)

P1, CPDLC RCP 400

P2, CPDLC RCP 240

P3, SATVOICE RCP 400

P4-P9, Reserved

These are to be further explained in block#18 behind the DAT/ and SUR/ entries. D-1 and G-1 entries will have a similar description for the ADS-C connection. MMEL and MEL's will need to be updated with this RCP/RSP information. Operators are cautioned that an MEL downgrade to RCP or RSP needs to be indicated on the current flight plan. Without a J-5 or J-7 code on the flight plan, expect to be denied routing thru FANS1/a required airspace due to ATOP computer programming. ATC expects this programming to be complete by summer of 2017. RCP400 and RSP400 are not tied to any reduced separation standards. Basically “P3” won’t do anything for you.

Bottomline

1. Flight plan equipment codes are dependent on installation, functionality and performance, not just an STC/TC installation

2. Pilots need to understand that “STBY” is a quick and legitimate response to ATC but, will NOT help improve response time performance monitoring

3. In most cases, prior datalink performance monitoring is required for operating approval

4. Problem reporting to POI's and regional monitoring agencies will be key to troubleshooting FANS communication and surveillance problems