"Boeing Fortress Mk I of No. 90 Squadron RAF based at West Raynham, Norfolk, 20 June 1941." Fortress Mark I, AN521 ‘WP-K’, of No. 90 Squadron RAF based at West Raynham, Norfolk, preparing for take off at Hatfield, Hertfordshire, during an inspection of newly-arrived American aircraft by the Chief of the Air Staff and the US Air Attache.