wiki/ TridentSpin
trident-2-dnsc8906614.jpg
A Bad Day for the Trident Missile Program

We just couldn't turn down such a beautiful, stunning and awe-inspiring picture of a navigation system failure for our team's logo. It's astounding to us that both the rocket actually managed a full spiral without ripping itself apart and that range safety hadn't destroyed it yet.

We borrowed the picture from the Federation of American Scientists web site: http://www.fas.org/nuke/guide/usa/slbm/d-5.htm. The page contains details on the Trident II D-5 submarine-based intercontinental ballistic missile. The rocket in the picture is consistent with this based on its markings and it's sea-based launch.

We can't find any official information on this failure, but a nice fellow emailed us with the following information:

[There] was a failure of the thrust vector control system. There are 2 perpindicular Hydrualic rams which position the nozzle for steering. One ram was snapped when it exited the water, hence control system lost control in one axis.

The Trident II is much larger than the Trident I and the way the water reacted is different. When the Trident II missile shot through the water into the air it brought up a water column with it. When the motor ignited the hot gas slammed into the water which was still in the nozzle. The resulting stress broke one of the hydraulic actuators for the nozzle. After they figured out what had happened, they changed the launch scenario (temporarily). For the second missile test, they increased the speed of the submarine at launch. The missile tilted and shot out of the water at an angle, the water column did not follow into the nozzle, the missile worked. Third test, for whatever reason they slowed the sub back down, missile broke.

Ultimately they fixed it by, beefing up the actuators, installing a nozzle cover, and surrounding the base of the nozzle with an innertube like device called a snubber see link [design # 2] http://www.ilcdover.com/products/aerospace_defense/inflatablestructures/trident.htm

If you have any more information on this launch, feel free to drop us a line and let us know!