Thanks for the information SalmonBug, let experimented people speak !
in clean config, a airliner would easily track a 3 degrees glide slope in idle and the speed would be very hig
That reminds me of the 'Caravelle' (the first airliner in the world with both engines located at the rear of the fuselage) : it was a real glider
! Glide slope was lesssssssssss than 3 degrees...