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NORMAL OPERATIONS
TAKEOFF
A330/A340 FLEET NO-050 P 5/12
FCTM 17 JUN 09
The minimum tail clearance occurs before lift off (due to rotating bogies).
MAIN FACTORS
EARLY ROTATION
Early rotation occurs when rotation is initiated below the scheduled VR. The potential reasons
for this are:
• The calculated VR is incorrect for the aircraft weight or flap configuration.
• The PF commands rotation below VR due to gusts, windshear or an obstacle on the runway.
Whatever the cause of the early rotation, the result will be an increased pitch attitude at lift-off,
and consequently a reduced tail clearance.
ROTATION TECHNIQUE
The recommendation given in the ROTATION TECHNIQUE paragraph should be applied.
A fast rotation rate increases the risk of tailstrike, but a slow rate increases take-off distance.
The recommended rate is between 2 and 3 °/s , which reflects the average rates achieved
during flight test, and is also the reference rate for performance calculations.
CONFIGURATION
When performance is limiting the takeoff weight, the flight crew uses TOGA thrust and selects
the configuration that provides the highest takeoff weight.
When the actual takeoff weight is lower than the permissible one, the flight crew uses FLEX TO
thrust. For a given aircraft weight, a variety of flap configurations are possible. Usually, the flight
crew selects the configuration that provides the maximum FLEX temperature. This is done to
prolong engine life.
On A340-500/600:
For any runway length, CONF 3 usually provides the highest FLEX temperature, and the tail
clearance at lift off does not depends on the configuration. So, the flight crew should select
CONF 3.
A330/A340 FLIGHT CREW TRAINING MANUAL
NORMAL OPERATIONS
TAKEOFF
A330/A340 FLEET NO-050 P 6/12
FCTM 17 JUN 09
On A330 and A340-300:
The configuration that provides the maximum FLEX temperature varies with the runway
length.
On short runways, CONF 3 usually provides the highest FLEX temperature, and the tail
clearance at lift off does not depends on the configuration. So, the flight crew should select
CONF 3.
On medium or long runways, the second segment limitation becomes the limiting factor, and
CONF 2 or CONF 1+F becomes the optimum configuration, in term of FLEX temperature.
In these cases, the tail clearance at lift off depends on the configuration. The highest flap
configuration gives the highest tailstrike margin.
There is a difference between twin and quadri, regarding this concern: The A330 has more
tail clearance than the A340, that has quite often, takeoff speeds closer to VMU limitation.
This is true with one engine inoperative. Since twin aircraft have more thrust margin for
takeoff, this is even more the case with all engines operative.
On A340-300, selecting CONF 3 instead of 1+F increases the tail clearance by 1.5 to 2 ft, at
the expense of a loss in FLEX temperature generally less than 3 °C.
Note: detailed effect:
• From CONF 1+F to CONF 2: Tail clearance increased by 0.5 to 1 ft, loss in FLEX
temperature generally less than 1 °C.
• From CONF 2 to CONF 3: Tail clearance increased by 1 ft, loss in FLEX
temperature generally less than 2 °C.
The first degrees of flexible thrust have an impact on maintenance costs about 5 times higher
than the last one.
A330/A340 FLIGHT CREW TRAINING MANUAL
NORMAL OPERATIONS
TAKEOFF
A330/A340 FLEET NO-050 P 7/12
FCTM 17 JUN 09
Summary:
On A340-200/300, taking the above into consideration, the crew may decide to select CONF
2 or CONF 3:
• When the FLEX temperature is close to TREF, it is advisable to select one more step of
flaps (compared to the optimum one).
• When the FLEX temperature is more than 15 °C above TREF, it is advisable to select
CONF 3.
TAKEOFF TRIM SETTING
The main purpose of the pitch trim setting for takeoff is to provide consistent rotation
characteristics. Takeoff pitch trim setting is automatic on ground on the A340-500/600,
A330/A340 Enhanced (with specific aircraft definition) and aircraft equipped with automatic trim
setting function . It is set manually via the pitch trim wheel on other A330/340 models.
The aircraft performs a safe takeoff, provided the pitch trim setting is within the green band on
the pitch trim wheel.
However, the pitch trim setting significantly affects the aircraft behaviour during rotation:
• With a forward CG and the pitch trim set to the nose-down limit the pilots will feel an aircraft
“heavy to rotate” and aircraft rotation will be very slow in response to the normal take off stick
displacement.
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A330/A340机组训练手册FLIGHT CREW TRAINING MANUAL(37)
