Acceleration check procedure for liners
Time and again after incidents like the S7 at Domodedovo, I wonder if during T/O liners don’t have any sort of acceleration check or similar procedure, to confirm that the engines are performing as expected during the first stage of the T/O run.
In my “outfit” (I know, I know, totally different kind), we do a TOLD calculation prior every flight. This calculation will amongst other things show the expected rotation and T/O speed, T/O distance and acceleration check speed.
The acceleration check speed will normally be calculated for a distance of 1000’ from brakes release. The 1000’ normally equals the distance to the first distance to go marker (normally only present on military fields), but any other visible or displayable feature will work (intersection, distance from mark point generated at brakes release position). The TOLD calculation takes the following data into account: Power setting (MIL or A/B T/O), weight, temperature, pressure, wind, runway conditions (friction, slope, length).
If the expected speed is not reached (+/- 5 KTS in MIL and +/- 10 KTS in A/B) when passing the ref. point, or if rotation or T/O speed is not reached at the expected point, T/O is to be aborted (A/B, provided there is enough RWY left) or full A/B is to be selected (MIL).
This method gives an early indication if all is well, or if the pilots should increase thrust/abort. In cases like the S7, where the wrong weight is put into the system, it will be perfectly clear by the lack of proper acceleration. There most be something like this in the civil world, or?