(b)
Pitch Multi-Channel Engage
1) Pitch multi-channel engage occurs at 1500 feet radio altitude if G/S and LOC are captured and two or more channels are armed. The flight mode annunciator on the EADI shows FLARE as the pitch armed mode. a) Flare is engaged when the main gear is 50 feet above
the ground. A throttle retard command is sent to the autothrottle to control vertical position to a point 500 feet past the glideslope intercept point. The descent rate at touchdown is 2 feet per second.
b) At radio altitude of less than 5 feet, a nose-down command is applied to the elevators to ensure nose wheel steering is affective.
(22) Windshear
(a) The autoflight windshear system causes the airplane to climb out of a windshear when in the TO or GA modes, or when both flight director switches are off and autopilot is not in CMD. The system is started when one of the go-around switches is pushed. If the usual AFDS pitch commands do not cause a sufficient rate of climb (at least 1200 fpm), the AFDS smoothly changes to a 15 degree pitch attitude or a little less than the pitch limit indicator, whichever is less.
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22-12-00
ALL ú ú 06 Page 54 ú Dec 20/94
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757 MAINTENANCE MANUAL
COMMAND ENGAGE SWITCHES
SLOPE GLIDE CL SEE A APPROACH MODE SELECT SWITCH/LIGHT
GO-AROUND
SEE B
RUNWAY THRESHOLD THRUST LEVERS
GO-AROUND SWITCHES
FWD
PITCH GO-AROUND_______________
A B . GO-AROUND ARMED WHEN A CHANNEL NOT COMMAND ENGAGED SWITCH IN ON OR OFF POSITION FOR . F/D CUE SHOWS ON EADI, WITH F/D GO-AROUND SWITCH PRESSED 2000 FPM RATE OF CLIMB SPEED TO SELECTED IAS/MACH TO ENTER ANOTHER MODE . COMBINED A/T AND FCC MODES SPEED IF AUTOTHROTTLE SPEED . THROTTLES ADVANCE TO ACHIEVE POSITION IF SELECTED ALTITUDE . SPEED THROUGH ELEVATOR CONTROLS . MUST BE ABOVE 500 FT RADIO ALTITUDE . AUTOMATIC TRANSITION TO VERTICAL . AUTOMATIC TRANSITION TO VERTICAL SELECTED APPROACHED
Pitch Channel - Go-Around Mode Figure 16 (Sheet 1)
D01232
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GUN 001-050, 052-999 ú 22-12-00
ú ú 06 Page 55 ú Dec 20/94
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757 MAINTENANCE MANUAL
COMMAND ENGAGE SWITCHES
FLIGHT DIRECTOR CAPTAIN'S ON/OFF SWITCH SLOPE CL GLIDE SELECT SWITCH/LIGHTS APPROACH MODE FLIGHT DIRECTOR ON/OFF SWITCH FIRST OFFICER'S
SEE C GO-AROUND
SEE D
RUNWAY THRESHOLD LEVERS THRUST
SWITCHES GO-AROUND
FWD
PITCH GO-AROUND_______________
C D . F/D CUE SHOWS ON THE EADI WITH POSITION TO ENTER ANOTHER MODE 2000 FPM RATE OF CLIMB GO-AROUND SWITCH PRESSED . GO-AROUND ARMED WHEN . AUTOMATIC TRANSITION TO VERTICAL . AUTOMATIC TRANSITION TO VERTICAL . MUST BE ABOVE 500 FT RADIO ALTITUDE . SPEED THROUGH ELEVATOR CONTROLS POSITION IF SELECTED ALTITUDE . THROTTLES ADVANCE TO ACHIEVE . COMBINED A/T AND FCC MODES SPEED TO SELECTED IAS/MACH SPEED IF AUTOTHROTTLE SPEED THE F/D SWITCH IN THE ON OR OFF SELECTED APPROACHED
Pitch Channel - Go-Around Mode Figure 16 (Sheet 2)
C70528
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22-12-00
ú ú 02 Page 56 ú Dec 20/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A 757 MAINTENANCE MANUAL
COMMAND ENGAGE SWITCH/LIGHTS
MULTICHANNEL ENGAGE
. LOC AND G/S CAPTURED . OTHER CHANNELS ARMED MANUALLY OR AUTOMATICALLY . MULTICHANNEL ENGAGE AT 1500 FT RADIO ALTITUDE . FLARE ARMED ANNUNCIATION AT MULTICHANNEL ENGAGE
FLARE ENGAGE____________ _______________NOSE WHEEL DOWN
. FLARE STARTS AT 50 FT . BEGINS AT RADIO ALTITUDE
GEAR HEIGHT LESS THAN 5 FT
. THROTTLE RETARD COMMAND TO . NOSE DOWN ELEVATOR THROUGH
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