Flight Operations Briefing Notes Takeoff and Departure Operations Understanding Takeoff Speeds(4)

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If an incident occurs before V1, the PNF’s attention may be focused on trying to assess the situation and may forget the V1 announcement.

Flight Operations Briefing Notes
Understanding Takeoff Speeds
.  In the event of an engine failure after takeoff, and in an attempt to climb faster, there may be a tendency to set a pitch attitude too high, if FD bars are not followed. The aircraft is then flown below V2, and climb performance cannot be ensured, as illustrated in Figure 5.

IV Prevention Strategies and Lines of Defense
The following strategies help to prevent takeoff speed errors. Airlines should:
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Define and use good CRM practices for takeoff speed computation and crosscheck.

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Conduct a takeoff briefing that highlights takeoff speeds, slats/flaps configurations, and weight, depending on the daily weather conditions. Attention should be paid to takeoff speeds, particularly if they were changed during taxi, in order to detect possible keystroke errors.

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For aircraft that are not equipped with a V1 auto-callout: close attention to the V1 standard callout should be paid.

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Emphasize that, once airborne, pilots should always follow the Flight Director’s pitch guidance bar and should consider using the autopilot in the event of an engine failure. This will considerably reduce the flight crew’s workload during demanding flight phase situations.

V Summary of Keypoints
Takeoff speed calculation errors are often due to a combination of two factors:
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Error in parameter entry

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Poor crosschecks by other crewmember.

Prevention strategies should be developed to ensure efficient crosschecks, particularly after last-minute changes (runway change, loadsheet modification…).

VI Associated Flight Operations Briefing Notes
The following Flight Operations Briefing Notes should be reviewed along with the above information:
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Conducting Effective Briefings

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Preventing Tailstrike at Takeoff

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Revisiting the “Stop or Go” Decision

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Preventing Runway Excursions and Overruns at Takeoff

Flight Operations Briefing Notes
Understanding Takeoff Speeds

VII Regulatory References
.  JAR/FAR 25.107 Subpart B – Takeoff Speeds

VIII Airbus References
The following Airbus brochure provides more performance-oriented information concerning takeoff speeds:
.  “Getting To Grips with Aircraft Performance”

IX Additional Reading Material
Example of events linked to takeoff speeds are available in the following documents:
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Transportation Safety Board of Canada – 2002 Air Investigation Reports – 14 June 2002 (www.tsb.gc.ca/en/reports/air/2002)
　
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