background image

AIM

10/12/17

1−2−5

Performance−Based Navigation (PBN) and Area Navigation (RNAV)

support LNAV minima. LNAV/VNAV incorporates

LNAV lateral with vertical path guidance for systems

and operators capable of either barometric or WAAS

vertical. Pilots are required to use WAAS to fly to the

LPV or LP minima. RNP APCH has a lateral

accuracy value of 1 in the terminal and missed

approach segments and essentially scales to RNP 0.3

in the final approach. (See paragraph 1−1−18.)

(2) RNP AR APCH. RNP AR APCH

procedures are titled RNAV (RNP). RNP AR APCH

vertical navigation performance is based upon

barometric VNAV or WAAS. RNP AR is intended to

provide specific benefits at specific locations. It is not

intended for every operator or aircraft. RNP AR

capability requires specific aircraft performance,

design, operational processes, training, and specific

procedure design criteria to achieve the required

target level of safety. RNP AR APCH has lateral

accuracy values that can range below 1 in the terminal

and missed approach segments and essentially scale

to RNP 0.3 or lower in the final approach. Operators

conducting these approaches should refer to AC

90-101A, Approval Guidance for RNP Procedures

with AR. (See paragraph 5−4−18.)

(3) Advanced RNP (A-RNP).  Advanced

RNP includes a lateral accuracy value of 2 for oceanic

and remote operations but not planned for U.S.

implementation and may have a 2 or 1 lateral

accuracy value for domestic en route segments.

Except for the final approach, A-RNP allows for

scalable RNP lateral navigation accuracies. Its

applications in the U.S. are still in use.

(4) RNP 1.  RNP 1 requires a lateral

accuracy value of 1 for arrival and departure in the

terminal area and the initial and intermediate

approach phase.

(5) RNP 2.  RNP 2 will apply to both

domestic and oceanic/remote operations with a

lateral accuracy value of 2.

(6) RNP 4. RNP 4 will apply to oceanic and

remote operations only with a lateral accuracy value

of 4.

(7) RNP 0.3.  RNP 0.3 will apply to

rotorcraft only. This Nav Spec requires a lateral

accuracy value of 0.3 for all phases of flight except for

oceanic and remote and the final approach segment.

(b) Application of Standard Lateral Ac-

curacy Values. U.S. standard lateral accuracy values

typically used for various routes and procedures

supporting RNAV operations may be based on use of

a specific navigational system or sensor such as GPS,

or on multi−sensor RNAV systems having suitable

performance.

(c) Depiction of Lateral Accuracy Values.

The applicable lateral accuracy values  will be

depicted on affected charts and procedures.

c. Other RNP Applications Outside the U.S.

The FAA and ICAO member states have led

initiatives in implementing the RNP concept to

oceanic operations. For example, RNP−10 routes

have been established in the northern Pacific

(NOPAC) which has increased capacity and

efficiency by reducing the distance between tracks

to 50 NM. (See paragraph 4−7−1.)

d. Aircraft and Airborne Equipment Eligibility

for RNP Operations. Aircraft meeting RNP criteria

will have an appropriate entry including special

conditions and limitations in its Aircraft Flight

Manual (AFM), or supplement. Operators of aircraft

not having specific AFM−RNP certification may be

issued operational approval including special condi-

tions and limitations for specific RNP lateral

accuracy values.

NOTE−

Some airborne systems use Estimated Position Uncer-

tainty (EPU) as a measure of the current estimated

navigational performance. EPU may also be referred to as

Actual Navigation Performance (ANP) or Estimated

Position Error (EPE).

3/29/18

AIM