01 - TRAINING OBJECTIVE
.
To determine the correct approach speed for normal and abnormal landing configurations
.
To understand the mini ground speed function.
02 - SCHEDULE
Briefing duration : 20 minutes
03 - EQUIPMENT
DOC references :
.
QRH 2.20 to 2.24
.
QRH 4.01
.
FCOM 1.22.30 (Flight Guidance)
.
FCOM 3.04.10 (Operating speeds definition)
.
FCOM 4.03.20 (MCDU Page Description)
04 - INSTRUCTOR’S ACTIONS
Briefing of the following key points.
MAIN
.
Minimum ground speed function
.
Normal approach speed
.
Approach speed for autoland
.
Approach speed in failure cases
.
Landing distance increments in case of failures
SECONDARY
A319/A320/A321 FLIGHT CREW TRAINING MANUAL NORMAL OPERATION BRIEFINGS PERFORMANCE 1.02.33 Page 4
REV 21 MAY 98
05 - TRAINEES’ ACTIONS
NORMAL CONFIGURATION
The VAPP displayed on the MCDU PERF APPR page is calculated using the following formula :
VAPP = VLS + 5 kts + 1/3 of the headwind component
NOTES :
.
VAPP is limited to VLS + 20 kt
.
Headwind component is computed from the wind inserted in the PERF APPR page
.
VLS is the VLS of the landing configuration (3 or FULL) selected on the PERF APPR page.
However the pilot may overwrite the VAPP according to the following formula:
{ VLS { or
VAPP = the greater of { VLS + 5 kt *
{ or
{ VLS + wind correction
NOTES :
.
The 5 kt* correction is an airworthiness requirement for autoland with A/THR, or approaches with A/THR active.
.
Wind correction is 1/3 of headwind component of reported tower wind, limited to 15 kt. Use the reported steady wind not the gust.
.
When there is a gusty crosswind greater than 20 kt, add 5 kt to VAPP (VAPP may now be up to VLS + 20 kt)
When CONF 3 is used for landing the CONF 3 prompt on the PERF APPR page should be pressed. The VLS on the PERF APPR page will change to VLS CONF3. VAPP should then be determined in the normal manner and managed speed used for the approach.
A319/A320/A321 FLIGHT CREW TRAINING MANUAL NORMAL OPERATION BRIEFINGS PERFORMANCE 1.02.33 Page 5
REV 21 MAY 98
05 - TRAINEES’ ACTIONS (CONT’D)
GROUND SPEED MINI FUNCTION
This function will compute a target IAS on approach in order to maintain a minimum aircraft energy level. The minimum energy level is an FMGS computed minimum ground speed (GS mini). This GS mini is not displayed to the crew but is used by the FMGS to calculate the IAS target on approach with managed speed. The relationship between VAPP, GS mini and approach IAS target is shown below.
VAPP = calculated in the manner described above and displayed or overwritten on MCDU PERF APPR page.
GS mini = VAPP - Tower headwind component
The headwind is counted as a positive value with a minimum value of 10 kt. For example if the headwind is less than 10 kt or there is a tailwind GS mini = VAPP -10 kt
IAS target = Maximum of VAPP or GS mini + Current Headwind Component
Current Headwind is counted positively and tailwind negatively.
The following extreme example should demonstrate how this function affects target speed :
-Approach to Runway 15R
-Tower wind in PERF APPR page : 150/45
-VLS = 130 kt
From the first two formulae above we get the following speeds :
-VAPP = 140kt (130 kt + maximum of 5 kt or 1/3 of 30 kt)
-GS mini = 110 kt (140 kt - 30 kt)
Altitude Current wind GS mini VAPP IAS target
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