Hello again. Sorry for the late response as I got stuck in a busy pattern after the sim.
FE Hoppy thanx for the reference I was looking for. Perhaps I did'nt pay proper attention to the terminologies used i.e "Margin" and "Factor" in my last post.
If I have understood correctly now then to land within 60% of the landing distance available means 40% of the landing distance available will be there for us as a safety margin.
i.e. If landing distance avaialble is 10,000 feet then aircraft has to stop
within 6000 feet so that the remaining 4000 feet is avaialable as a
safety margin. The remaining 4000 feet is 40% safety margin in
reference to landing distance available and 67% safety margin in
reference to landing distance in which the aircraft stops.
Thus in reference to the aircraft actual landing performance
Margin of Safety = 67%
Safety Factor = 1.67
Whereas in reference to landing distance avaialble the margin of safety = 40%
Thankyou all