In early January 1915 Haig summoned Trenchard to explain what might be achieved in the air war. During the meeting, Haig brought him into his confidence regarding plans by the First Army for a March attack in the Merville/Neuve Chapelle region. After aerial photographic reconnaissance had been gathered, the British plans for the attack were reworked in February in consequence. During the Battle of Neuve Chapelle in March the R.F.C., and especially the First Wing, supported the operation. This was the first time that aircraft were used as bombers with missiles strapped to the wings and fuselage as opposed to being released by hand which had happened earlier in the war. However, the bombing from the air had little effect due to limited weight payload capacity, and the Royal Artillery disregarded the information provided by the R.F.C.'s airmen. Prior to the British First Army's offensives at Ypres and Aubers Ridge in April and May, the First Wing's crews flew reconnaissance sorties using aerial cameras over the German lines. Despite the detailed information this provided and the improved air-artillery cooperation during the battles, the offensives were inconclusive. At the end of this engagement Henderson offered Trenchard the position as his chief of staff. He declined the offer, citing his unsuitability for the role, although his ambition for command may have been the real reason. In any case, this did not stop his promotion to full colonel in June 1915.