PJ, thanks. I had seen the NLR study.
I was instrumental in a similar task many years ago, but with lesser recording and analysis capability.
One aspect which might be relevant in the NLR study and with your point of touchdown is the assumption that the ILS beam is a straight line at low altitude.
Because the ILS GS is a reflected beam it will show a parabolic path along the runway, tending to be above the 3 deg ideal at lower altitudes. In operations this is not significant particularly as autoland systems tend to fade out the GS and incorporate attitude stability until flare.
These new (real data) risk assessment methods are attractive because as the risks are identified their significance can be related to specific operations, thence proactive safety action considered and the findings communicated to all crews – participation.
In particular, I like the possibility of using the data store and analysis as a means of real time risk assessment for all aircraft via the growing communication capabilities; turning the hindsight of previous (acceptable) landings in the data base into foresight for some of the significant parameters in a pending landing, e.g. reconsider flap setting, increase brake setting. This machine based decision aiding might also strengthen the human decision processes, which is still essential for ill-determined parameters – accuracy of reported runway condition, wind, etc.
Overall these activities could provide the crew with awareness of the available safety margin for each approach and the need to adjust, or be aware of the need for accuracy in touchdown, speed, etc.
An interesting point is the correlation of touchdown positon with a limiting runway (seen in other data) – why do pilots touchdown earlier, yet on longer runways they do not; cue the psychologists.
SESMA