The computer used was the Stabilized Automatic Bomb Sight - a more accurate form of the Norden bomb sight that was used for daylight raids by the USAAF during the War. This bomb sight was issued to specialist units such as IX and 617 Squadrons to allow them to drop their single big bombs with more accuracy. The usual main force bomb sight at this time was the Mk XIV which was excellent for use during night bombing but not as accurate during daylight. The T1 series of sights were developed for use post war as the Lancaster sights were not deemed suitable for the faster aircraft that came along later (and eventually replaced by radar bombing systems).
Last edited by Wensleydale; 31st Mar 2014 at 12:27.