RNP AR Instrument Approach Procedures

Introduction:

  • RNP AR procedures require authorization analogous to the special authorization required for Category II or III ILS procedures
  • All operators require specific authorization from the FAA to fly any RNP AR approach or departure procedure
  • The FAA issues RNP AR authorization via operations specification (OpSpec), management specification (MSpec), or letter of authorization (LOA)
  • There are no exceptions. Operators can find comprehensive information on RNP AR aircraft eligibility, operating procedures, and training requirements in AC 90-101, Approval Guidance for RNP Procedures with AR

Unique Characteristics of RNP AR Operations Approach Title:

  • The FAA titles all RNP AR instrument approach procedures (IAP) as "RNAV (RNP) RWY XX"
    • Internationally, operators may find RNP AR IAPs titled "RNP RWY XX (AR)
  • All RNP AR procedures will clearly state "Authorization Required" on the procedure chart
  • RNP value:

    • RNP AR procedures are characterized by use of a lateral Obstacle Evaluation Area (OEA) equal to two times the RNP value (2 x RNP) in nautical miles
      • No secondary lateral OEA or additional buffers are used
    • RNP AR procedures require a minimum lateral accuracy value of RNP 0.30
    • Each published line of minima in an RNP AR procedure has an associated RNP value that defines the procedure's lateral performance requirement in the Final Approach Segment
    • Each approved RNP AR operator's FAA-issued authorization will identify a minimum authorized RNP approach value
      • This value may vary depending on aircraft configuration or operational procedures (e.g., use of flight director or autopilot)
  • Radius-to-fix (RF) legs:

    • Many RNP AR IFPs contain RF legs
    • Aircraft eligibility for RF legs is required in any authorization for RNP AR operations
  • Missed Approach RNP value less than 1.00 NM:

    • Some RNP AR IFPs require an RNP lateral accuracy value of less than 1.00 NM in the missed approach segment
    • The operator's FAA-issued RNP AR authorization will specify whether the operator may fly a missed approach procedure requiring a lateral accuracy value less than 1.00 NM
    • AC 90-101 identifies specific operating procedures and training requirements applicable to this aspect of RNP AR procedures
  • Non-standard Speeds or Climb Gradients:

    • RNP AR approaches may require non-standard approach speeds and/or missed approach climb gradients
    • RNP AR approach charts will reflect any non-standard requirements and pilots must confirm they can meet those requirements before commencing the approach
  • RNP AR Departure Procedures (RNP AR DP):

    • Example of an RNP AR DP
      Example of an RNP AR DP
    • RNP AR approach authorization is a mandatory prerequisite for an operator to be eligible to perform RNP AR DPs [Figure 1]
    • RNP AR DPs can utilize a minimum RNP value of RNP 0.30, may include higher than standard climb gradients, and may include RF turns
    • Close in RF turns associated with RNP AR DPs may begin as soon as the departure end of the runway (DER)
    • For specific eligibility guidance, operators should refer to AC 90-101
    • Example of an RNP AR DP
      Example of an RNP AR DP

Conclusion:

  • To learn more about instrument procedures, be sure to check out the Instrument Procedures Handbook online or in paperback
  • Pilots can visit the FAA's Instrument Flight Procedures Information Gateway to review and submit questions related to the how and why certain procedures are as they are
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