This week Matt talks about how runway braking actions are reported and the new technology helping to improve it.

Airbus and its subsidiary NAVBLUE have developed a new technology to use the aircraft itself as a sensor to measure the available runway braking action, and subsequently share that data to the benefit of oncoming traffic and the airport authorities.

There are two new system developments discussed in this episode,

TOS (Take off surveillance) which comprises of TOS1 and TOS2, and,

TOM (Take off monitoring) which currently isn’t available on the A320 but is being evaluated for possible installation.

TOS1 checks flaps and trim settings and does a check of the performance parameters entered in the FMS (aircraft weight and takeoff speeds). This then compares actual performance settings with that entered in the FMS.

TOS2 makes the same checks as TOS1, but additionally, checks that the aircraft is positioned on the intended runway and that the expected takeoff performance – based on data entered in the FMS by the crew,  is compatible with the runway distance available.

If any of these checks compute an error, various ECAMs can be triggered.

TOM monitors the acceleration of the aircraft during the takeoff phase and warns you if a lower-than-expected acceleration is detected. From 30 kt, it compares the expected acceleration with the real acceleration of the aircraft. If the difference between the real aircraft acceleration and its expected acceleration is more than 15 % when the aircraft reaches 90 kt, TOM will trigger the red ECAM warning T.O ACCELERATION DEGRADED

Airbus recommends rejecting a takeoff if you get any of these uninhibited ECAMs on the takeoff roll.