Unreliable airspeed at Takeoff
Since the beginning of 2020, Airbus has received an increasing number of reports of unreliable airspeed events at takeoff due to Pitot probe obstruction. Despite the existing prevention means and the preflight exterior walkaround, takeoffs with obstructed air data probes may happen. This article highlights why it is so important for pilots to actively monitor the airspeed during the entire takeoff roll, to detect an airspeed discrepancy as early as possible, and safely reject the takeoff, if required to do so.
A Focus on the Takeoff Rotation
An appropriate takeoff rotation maneuver is a balance between good takeoff performance and sufficient margin versus tail strike, stall speed, and minimum control speeds.Applying the 3°/s rotation rate requested in the SOPs is the key to ensure that the aircraft meets the expected takeoff performance. Flight data monitoring shows that the rotation rate values in service vary and a lower rotation rate is observed in some cases with the associated degradation of takeoff performance. This article describes both the takeoff rotation laws available on Airbus Fly-by-Wire (FBW) aircraft and the recommended rotation techniques that will enable flight crew to achieve consistent takeoff rotations at the requested rotation rate.
Takeoff Surveillance & Monitoring Functions
Airbus has continuously improved takeoff safety since the “TO CONFIG TEST” pushbutton was first introduced on A300 and A310 aircraft, and with the development of the Takeoff Surveillance (TOS1 & TOS2) and Takeoff Monitoring (TOM) functions.The TOS2 package that was initially developed for the A350 is now available for A320 family and A330 aircraft. This is an opportunity to review the checks that are performed by each function, from cockpit preparation to takeoff.
Control your speed… at take-off
One of the most critical decisions that every line pilot may potentially encounter during every take-off is to continue or abort the procedure; hence the essential need to properly monitor the airspeed during this phase.
Airbus Brake Testing
Regulatory aircraft performance is certified as a set of performance models and aircraft physical characteristics that are built and validated from flight test data. While the primary purpose of these models has always been to allow computation of aircraft performance for dispatch, the models used to determine the in-flight landing distances during approach preparation are derived from the same testing. Part of this model, affecting both the accelerate-stop computation at take-off and the landing distance computation, are the characteristics of the braking system installed on the aircraft.This article explains which flight tests are involved in the identification of the system characteristics and how they are conducted.