FDXmech From United States of America, joined Mar 2000, 3251 posts, RR: 34
Reply 3, posted (13 years 9 months 3 weeks 2 days 8 hours ago) and read 1230 times:
This DC10 although the main gears are on the ground, the main gears are still at full oleo extend meaning that the struts haven't yet compressed. If you notice, the auto ground spoilers have not yet deployed. Also the center gear on the DC10-30 is canted so the wheels are angled forward of the trunnion (the trunnion is where the gear mounts to the fuselage and is the pivot point during retraction/extension)which in effect creates an angle that causes the center gear to contact the ground after the mains compress. In other words if you observed a DC10-30 parked at the gate, the center gear is not vertical but tilted with the tires closer to the nose than the top of the gear. When the aircraft settles (ground spoilers extend and struts compress) the center gear will contact the runway even if the nose gear is still in the air. While I'm boring you with this I might as well stick in one more thing totally unrelated to the question asked. On the DC10-30/MD11 but not the DC10-10 (no center gear) because of the built in angle of the center gear, loading of the a/c must be accomplished with the parking brake released to allow the center gear to move with the changing weight of the aircraft. Otherwise over time damage due to stress will occur.