737 MAX Flight Crew Operations Manual
Warning Systems -
System Description
MN-FLT-OH-201
15.20.21
The Enhanced Ground Proximity Warning System (EGPWS) monitors the
position of spoiler panels 4 and 9. The speedbrake alert activates if these spoiler
panels are less than halfway up three seconds after touchdown or after the
initiation of a rejected takeoff above 80 knots.
The speedbrake alert is inhibited if Hydraulic System A has low pressure (spoiler
panels 4 and 9 are powered by Hydraulic System A).
Windshear Alerts
Windshear alerts are available during takeoff, approach, and landing:
• The GPWS provides a warning when the airplane is in a windshear.
• The weather radar provides alerts for excessive windshear ahead of the
airplane. These are “predictive windshear alerts.”
Windshear warnings are accompanied by a red WINDSHEAR message on the
attitude indicators and voice aural alerts.
Windshear cautions are accompanied by a voice aural alert.
Windshear alerts are prioritized based on the level of hazard and the required flight
crew reaction time. Predictive windshear alerts are inhibited by an actual
windshear warning (airplane in windshear), look-ahead terrain alerts, or radio
altitude based alerts.
Windshear Warning (Airplane in Windshear)
Predictive Windshear Alerts
The weather radar uses radar imaging to detect disturbed air prior to entering a
windshear.
Note:
The weather radar provides windshear alerts for windshear events
containing some level of moisture or particulate matter.
Note:
The weather radar detects microbursts and other windshears with similar
characteristics. The weather radar does not provide alerting for all types of
windshear. The flight crew must continue to rely on traditional windshear
avoidance methods.
AURAL ALERT
VISUAL ALERT
DESCRIPTION
Two–tone siren
followed by
WINDSHEAR,
WINDSHEAR,
WINDSHEAR
Red
WINDSHEAR on
both attitude
indicators.
Excessive windshear at the current
airplane position detected by GPWS.
Enabled below 1,500 feet RA.
GPWS Windshear detection begins at
rotation.
October 26, 2021