B. The distance from stem end of roll a.

Tiles) Microwave scanning beam landing system. 6-36 DEORBIT BURN 60 MIN TO TOUCHDOWN 25 338 m (83 130 FT) 2735 km/H (1700 MPH) AUTOLAND 86 SEC TO TOUCHDOWN 4074 m (13 365 FT) 682 km/H (424 MPH) 4074-m (13 365-FT) ALTITUDE INITIATE PREFLARE 32 SEC TO TOUCHDOWN.