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Define adequate normal and abnormal flight crew procedures,
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Validate the FMS navigation database coding,
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Evaluate the absence of TAWS warning when the aircraft is on the nominal flight path.
7.1.1 NORMAL CONDITIONS (NO FAILURE)
During this evaluation, the effect of the aircraft design must be taken into consideration and evaluated in variable conditions such as normal or rare wind and temperature conditions. As necessary wind and/or temperature limitations may have to be defined in addition to the temperature limitation, which may be mandated by the design criteria of RNP AR approach procedures.
The use of AP is required for RNP<0.3 and is recommended for RNP=0.3.
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7. RNP AR Operations and Training
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The capacity of the AP to fly an RF leg is a function of the radius of turn, IAS, altitude, OAT and wind conditions. With all engines operative (AEO), the bank angle is limited to 30°. Airspeeds, RF radii and bank angles are linked values. The operator has to check during the operational evaluation that sufficient margin is available between the nominal bank angle to fly the turn and the aircraft roll limit. A 5° bank angle margin between the bank limit and the nominal bank angle (no wind) is usually considered as sufficient to fly a RF leg under normal wind conditions.
The FTE performance demonstration during certification has been made with a maximum ground speed function of the RF turn radius. The table below gives for a nominal bank angle of about 20° the TAS function of the turn radius R and the wind intensity. The wind intensity (in kt), whatever the wind direction is, should be subtracted to the listed figure. Ex: R 1.6 NM, Wind = 30 kt...
.Max TAS = 170 kt
Turn Radius R in NM Max TAS in Kt
0.8 1 1.2 1.4 1.6 1.8 2 R>2.2 141-wind 158-wind 173-wind 187-wind 200-wind 212-wind 222-wind 233-wind
7.1.1.1 GO AROUND AP/FD MODE
For the majority of SA and LR aircraft, at GA initiation, the AP/FD mode will revert from NAV, APP NAV or FINAL APP to GA TRK mode and will maintain the previous track filtered by a 15s time constant, until the NAV mode is re-engaged by the flight crew. Therefore, prompt re-engagement of NAV mode is required after go-around initiation to remain on the lateral flight path.
For the aircraft with this AP/FD definition the minimum RNP certified by EASA is 0.3 NM during missed approach. New standard of the Flight Guidance part of FMGC are, or will be, certified to implement an automatic NAV mode reengagement at go around initiation. With these standards RNP<0.3 are, or will, be approved in missed approach. Initiation of missed approach from any point in the approach, including during RF legs, should be assessed, during the operational evaluation. A missed approach must be considered from any point of the approach, and obstacle clearance must be considered with respect to the certified RNP.
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