Hi BOAC,
It may be as c100 driver points out. Our manuals were written by the company, based on Lockheed's original. I can remember the term "Alpha Floor" from the manual, but the aircraft only displayed "ALPHA" in the speed window.
It was autothrust adding power to prevent the speed from dropping further - more like AirBus VLS - not as AB does with full TOGA during ALPHA FLOOR. We usually left autothrust in for the approach (belt & braces to prevent flying less than VREF), and disengaged it before the flare.
Potential Tail Strikes (pitch > 10degs) were usually caused by flying too slowly just before the flare, leaving no room to pitch up for the landing.