Years ago I saw a film of a live demo by Boeing on the 727 in which they set up a 35' stick, and a camera at the DER and did a series of t/o's. Using all engines they did under rotation, over rotation, too slow a rotation, and too fast a rotation. On each of these 4 t/o's with all engines running they were under the 35' mark as they launched. On the last t/o, they pulled the center engine to idle at V1 and continued the t/o. With a normal rotation, they exceeded the 35' mark as they launched. This was a perfect illustration to a simple guy like me of the importance of proper rotation technique.
Last edited by 5LY; 6th Feb 2012 at 17:58.