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too fast. The Descent Procedure is normally initiated before the airplane descends
below the cruise altitude for arrival at destination, and should be completed by
10,000 feet MSL. The Approach Procedure is normally started at transition level.
Plan the descent to arrive at traffic pattern altitude at flaps up maneuvering speed
approximately 12 miles from the runway when proceeding straight-in or about 8
miles out when making an abeam approach. A good crosscheck is to be at 10,000
feet AGL, 40 miles from the airport, at 250 knots.
Losing airspeed can be difficult and may require a level flight segment. For
planning purposes, it requires approximately 45 seconds and 3 NM to decelerate
from 290 to 250 knots in level flight without speedbrakes. It requires an additional
45 seconds and 3 NM to decelerate to flaps up maneuvering speed at average gross
weights. Using speedbrakes to aid in deceleration reduces these times and
distances by approximately 30%.
Maintaining the desired descent profile and using the map mode to maintain
awareness of position ensures a more efficient operation. Maintain awareness of
the destination weather and traffic conditions, and consider the requirements of a
potential diversion. Review the airport approach charts and discuss the plan for the
approach, landing, and taxi routing to parking. Complete the approach briefing as
soon as practical, preferably before arriving at top of descent. This allows full
attention to be given to airplane control.
Speedbrakes
The pilot flying should keep a hand on the speedbrake lever when they are used
in-flight. This precludes leaving the speedbrakes extended.
Use of speedbrakes does not appreciably affect airplane roll response. While using
the speedbrakes in descent, allow sufficient altitude and airspeed margin to level
off smoothly. Lower the speedbrakes before adding thrust.
To avoid buffeting, use of speedbrakes with flaps greater than 5 should be avoided.
If circumstances dictate the use of speedbrakes with flaps extended, high sink
rates during the approach should be avoided. Speedbrakes should be retracted
before reaching 1,000 feet AGL.
The flaps are normally not used for increasing the descent rate. Normal descents
are made in the clean configuration to pattern or instrument approach altitude.
October 31, 2004
767 Flight Crew Training Manual
Climb, Cruise, Descent and
Holding
Copyright © The Boeing Company. See title page for details.
4.20 FCT 767 (TM)
When descending with the autopilot engaged and the speedbrakes extended at
speeds near VMO/MMO, the airspeed may momentarily increase to above
VMO/MMO if the speedbrakes are retracted quickly. To avoid this condition,
smoothly and slowly retract the speedbrakes to allow the autopilot sufficient time
to adjust the pitch attitude to maintain the airspeed within limits.
When the speedbrakes are retracted during altitude capture near VMO/MMO, a
momentary overspeed condition may occur. This is because the autopilot captures
the selected altitude smoothly by maintaining a fixed path while the thrust is at or
near idle. To avoid this condition, it may be necessary to reduce the selected speed
and or descent rate prior to altitude capture or reduce selected speed and delay
speedbrake retraction until after level off is complete.
Flaps and Landing Gear
Normal descents are made in the clean configuration to pattern or instrument
approach altitude. If greater descent rates are desired, extend the speedbrakes.
When thrust requirements for anti-icing result in less than normal descent rates
with speedbrakes extended, or if higher than normal descent rates are required by
ATC clearance, the landing gear can be lowered to increase the rate of descent.
Extend the flaps when in the terminal area and conditions require a reduction in
airspeed below flaps up maneuvering speed. Normally select flaps 5 prior to the
approach fix going outbound, or just before entering downwind on a visual
approach.
Note: Avoid using the landing gear for increased drag. This minimizes passenger
discomfort and increases gear door life.
Speed Restrictions
Speed restrictions below specific altitudes/flight levels and in the vicinity of
airports are common. At high gross weights, minimum maneuvering speed may
exceed these limits. Consider extending the flaps to attain a lower maneuvering
speed or obtain clearance for a higher airspeed from ATC.
Other speeds may be assigned by ATC. Pilots complying with speed adjustments
are expected to maintain the speed within plus or minus 10 knots.
Engine Icing During Descent
The use of anti-ice and the increased thrust required increases the descent
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767机组训练手册Flight Crew Training Manual (FCTM)767(56)
