Tuesday, April 11, 2006
Testing, Testing 1-2-4,500
The Phalanx Close-In Weapons System--CIWS (Sea Whiz) practicing earlier this month off Florida on the USS John Kennedy (CVN-67). It's in 20mm and uses armor piercing discarding sabot (APDS) bullets and the 6 barrels spinning put out 4,500 rounds per minute or 75 per second. Discarding sabots means that the bullet is slightly smaller than the 20mm width inside the barrel, but has a jacket that takes the lands and grooves of the barrel, spins down the length of the barrel and then flies off when the bullet clears the end. The skinny bullet (sub caliber penatrator) goes very fast. The bullets were in depleted uranium but are now in tungsten. Click on the photo and it will expand--then look at the business end of the barrels--you can almost see the displacement in the air caused by the passage of the rounds. This weapon is for the Exocet missile (or similar) that gets past the picket ships surrounding the carrier. The white dome contains the radar which directs the bullets down range to the target. When these things fire it sounds like the World's largest zipper working.