On 4 January 1967, weather conditions were finally suitable for an attempt. Campbell commenced the first run of his last record attempt at just after 8:45 am. "Bluebird" moved slowly out towards the middle of the lake, where she paused briefly as Campbell lined her up. With a deafening blast of power, Campbell now applied full throttle and "Bluebird" began to surge forward. Clouds of spray issued from the jet-pipe, water poured over the rear spar and after a few hundred yards, at , "Bluebird" unstuck from the surface and rocketed off towards the southern end of the lake, producing her characteristic comet's tail of spray. She entered the measured kilometre at 8:46 am. Leo Villa witnessed her passing the first marker buoy at about in perfect steady planing trim, her nose slightly down, still accelerating. 7.525 seconds later, Keith Harrison saw her leave the measured kilometre at a speed of over . The average speed for the first run was . Campbell lifted his foot from the throttle about 3/10 of a second before passing the southern kilometre marker. As "Bluebird" left the measured kilometre, Keith Harrison and Eric Shaw in a course boat at the southern end of the measured kilometre both noticed that she was very light around the bows, riding on her front stabilising fins. Her planing trim was no worse than she had exhibited when equipped with the Beryl engine, but it was markedly different from that observed by Leo Villa at the northern end of the kilometre, when she was under full acceleration. Campbell had made his usual commentary throughout the run.