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时间:2010-09-02 13:55来源:蓝天飞行翻译 作者:admin
曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

wheels on the ground and landing gear oleo was fully compressed, the angle is established to
less for the amount of the length extended the body as compared with A320.
(Refer Figure 2)
2.12.5 Outline of Wind-Shear Warning System and EGPWS equipped on the aircraft
The aircraft equipped with Reactive Type wind-shear warning system and Predictive
Type, as the equipment which alarms aural sound if it is forecasted to encounter to windshear
at take-off/landing, or if it is encountered. Further, if aircraft got close to the ground
etc. abruptly, it is also equipped with the warning system for EGPWS which alarms aural
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sound to such proximity.
The detection for wind-shear by Reactive Type out of the wind-shear warning system is
computed on the aircraft energy, variances of wind around the own aircraft due to the
difference between a ground speed and CAS, if it was detected that the wind speed change
over 23kt occurred within 30 seconds and so on, the synthetic aural sound is alarmed as
warning sound of “WIND SHEAR, WIND SHEAR, WIND SHEAR”. The operating range for
the system is covered from the altitude of 1,300ft AGL to 50ft AGL at the time of an
approach.
Contrary to this, the detection for wind-shear by Predictive Type was utilized with
Doppler Effect, which the radar wave reflected from the moving objects makes the frequency
change. Especially, if it detected such as the wind speed changes over 25kt occurred within
14 seconds in the range within forward 5nm from own aircraft, within laterally 0.5nm and
also angle of 25 degrees for left/right to the aircraft axis, the aural warning is issued. In
Predictive Type, because the objects observed by this radar are cloud and rain droplets, if
the phenomenon of precipitation for the droplets was not occurred, the wind-shear may not
detected. The predictive type computed on the CAS and vertical wind speed, etc.
Further, in Predictive Type, the warning is issued by display and aural sound in the
altitude from 1,200ft AGL to 50ft AGL. At the time, the synthetic sounds are issued as the
warning sounds of “GO AROUND WIND-SHEAR AHEAD”.
If aircraft got close to the ground abruptly, EGPWS compared the altitude at radio
altimeter with rate of descent. If these values exceed the specified limit range and enter in
the dangerous zone, it is the equipment which issued the warning sound to the pilot by
synthetic sound of “Sink Rate” etc. in correspondence with each circumstance. The operating
range of this equipment is established to the altitude from 2,450ft AGL to 10ft AGL.
The priority sequences related to the issuance for aural sound of warning in the each
equipment are established in the sequence of the Reactive Type of Wind Shear, the
Predictive Type one, then EGPWS. For example, during issuing the warning sound for
Reactive Type, another aural sound for the warning system is established to be inhibited.
2.12.6 Establishment of a Final Approach Speed
2.12.6.1 Establishing Method of Final Approach Speed
According to the Airplane Operations Manual (AOM) issued by ANA, as described in the
section 2.12.7, in establishing final approach speed on A321 airplane there are the method
established by “SELECTED SPEED” mode and the method established by “MANAGED
SPEED” mode. In the approach at the accident on the aircraft, the aircraft made an
approach with “SELECTED SPEED” mode. The establishment of a final approach speed
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with manual control by “SELECTED SPEED” mode is specified as follows:
(1) At first, the approach speed (VAPP) is computed as the following formula
VAPP = VLS + MIN (15, MAX (5, 1/3 of head wind component) )
(Note: MIN (A, B) means the smaller one of either A or B. MAX means the larger one.)
The minimum control speed (VLS ) is specified for the value kept the speed margin for
1.23 times of a stall speed (VS). VAPP is computed to add 1/3 of head wind component with
VLS. This addition is to keep the speed at or greater than VLS at flare because of the
effects of ground topography on the surface boundary layer. However, the value to be
added is specified within the limit of less than 5kt or under 15kt if being larger. Here, the
head wind component is computed by the average of the wind speed. More, the practical
computation for VAPP during a flight, is displayed on FMGC automatically if data is
entered.
(2) Then, the final approach speed, could be at or greater than VLS at flare even if the wind is
dropped rapidly, is established as adding gust component to VAPP by the following
formula:
Final approach speed = VAPP + (Maximum wind speed – Average wind speed)
(3) Further, a PF shall specify the final approach speed finally with the formula describing
 
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