(c)
CLIMB (CLB) phase CLIMB becomes active from TAKEOFF or GO AROUND phase when the aircraft altitude increases above the acceleration altitude or at pilot engagement of a vertical autopilot mode other than TO/GA. CLIMB is also recovered from DESCENT, APPROACH or CRZ phases each time the aircraft altitude becomes lower than the (possibly new) cruise altitude (except if there is a preplanned step).
(d)
CRUISE (CRZ) phase It becomes active from CLIMB, DESCENT or APPROACH phase each time the aircraft altitude becomes greater than or equal to the (possibly new) cruise altitude.
(e)
DESCENT (DES) phase It becomes active from CRUISE or CLIMB phase when the aircraft (not too far from the destination) begins a descent to a clearance altitude below the cruise or current A/C altitudes without preplanned step.
(f)
APPROACH phase
-
it becomes active from DESCENT when:
*
A/C is in MANAGED LAT CONTROL
*
and DECEL pseudo WPT is sequenced
*
and A/C Alt is below a specific value or
*
ACTIVATE APPR PHASE prompt is pressed on PERF/DES page.
-
it becomes active also from CLIMB, CRUISE or GA phase if the ACTIVATE APPR PHASE prompt is pressed on the related PERF page.
(g)
GO AROUND phase It becomes active from the CLB, CRZ, DES or APPROACH phase when the PITCH GO AROUND mode is engaged.
(h)
DONE phase It becomes active from any other phase than PREFLIGHT when engines are stopped and A/C is on ground. In addition, it may become active from APPROACH flight phase as soon as sufficient time elapsed with only aircraft on ground condition.
B. Speed Generation
(1) Optimization Several reference and optimum speeds are used for MCDU display, for performance computation and for guidance when MANAGED SPEED CONTROL is active. They are takeoff, approach and go around speeds, optimum climb, cruise and descent speeds, and situational speeds (as holding pattern speeds and managed descent speeds).
(a)
Takeoff, approach and go around speeds Characteristic takeoff speeds, F, S and O (Green Dot) are computed in Preflight and Takeoff phases using the performance model. They are computed with the Takeoff Weight (TOW) if it is available, else they are not computed. While not in Approach flight phase, the approach speeds are VLS (Lower Selectable Speed), default VAPP, Green Dot, S, and F. They are computed using the performance model with the predicted LW (Landing Weight) if available, with the current GW (Gross Weight) if not. At transition to Approach phase, these speeds are computed with the current GW. On the APPR page, the WIND and LDG CONF fields enable entry of additional approach data for better estimation of VLS and default VAPP. While not in Approach flight phase, the go around reference speeds, F, S and Green Dot are computed using the performance model with the predicted LW if available, with the current GW if not. At transition to Approach flight phase, they are computed using the current GW. At transition to go around flight phase, they are computed using the current GW. Takeoff, approach and go around speeds are displayed on the corresponding PERF pages. (Ref. Fig. 003) On the TAKEOFF page, additional speeds may be entered by the pilot to take them into account for prediction and guidance; they are the decision speed (V1), the rotation speed (VR) and the reference speed for initial climb (V2). V1 and VR are retransmitted to the PFD scale.
(b)
Optimum speeds All speeds defined in this paragraph are computed inside the speed envelope of the managed mode. Climb, cruise and descent optimum speeds are optimized (within above speed envelope) as functions of:
-
the Gross Weight (GW)
-
the Cost Index (CI)
-
the cruise flight level (CRZ FL)
-
the wind and temperature models. In Preflight phase, these speeds are computed using the TOW and the predicted weights at the various points of the F-PLN. If no TOW is available, no speed is computed. After transition to Takeoff phase, they are computed using the A/C GW and the predicted weights at the various points of the F-PLN. If no A/C GW is available, no speed is computed.
R F, S, Green Dot, VAPP and VLS Displays on PERF Page Figure 003
R 1EFF : 106-149, 151-199, 211-299, 301-399, 1 22-73-00Page 7 1401-499, 1Config-2 Aug 01/05 1 1 1CES 1 If there is no CRZ FL or no Cost Index, they default to Green Dot.
(c)
ECON speeds The ECON speeds are the optimum speeds for the given cost index which satisfy a time constraint (if one exists) and/or speed constraints (if they exist) and the speed envelope. If there is no time or speed constraint, the ECON speeds are the optimum speeds computed in para (b) above. They are displayed on the PERF page under the ECON prompt. (Ref. Fig. 004)
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：A320飞机维护手册 AMM AUTO FLIGHT 自动飞行4(3)
