mangin@brahms.udel.edu (Jeff Mangin) (05/20/91)
From: mangin@brahms.udel.edu (Jeff Mangin) [Sorry, I was wrong about the Hellfires missing. They were not Hellfires they were just rocket pods. I would still like some input on this subject. Thanks.] Yesterday, I was at APG, Maryland for Armed Forces Day to watch a live fire demonstration. Part of the show involved Cobra gunships with [Rocket Pods] and the 20mm three-barrel gun. The two gunships were firing at 10ftx10ft targets at 1/2 a mile away. Out of the 32 [Rockets] fired, no more than 4 hit the targets. Out of the rest fired, most missed by a large margin. When a gunship would fire two at once, one would hit about 100ft in front of the gunship and the other would head towards the target. The 20mm gun did no better. As a side note, I was very impressed with the Bradley's performance. Its main gun could hit the target while moving at a right angle to the target and jumping an obstacle. Any comments? Jeff
yarvin-norman@CS.YALE.EDU (Norman Yarvin) (05/21/91)
From: yarvin-norman@CS.YALE.EDU (Norman Yarvin) Unguided rockets are inherently inaccurate compared to guns because they generate thrust while in flight, and the direction of this thrust cannot be controlled well. Adding a guidance system turns thrust during flight into an advantage. The Hellfire is guided. Military shows probably use unguided rockets because they are cheaper.
hassall@amsaa-cleo.brl.mil (LTC James Hassall) (05/23/91)
From: LTC James Hassall <hassall@amsaa-cleo.brl.mil> mangin@brahms.udel.edu (Jeff Mangin) writes: > Yesterday, I was at APG, Maryland for Armed Forces Day to watch a live > fire demonstration. Part of the show involved Cobra gunships with > [Rocket Pods] and the 20mm three-barrel gun. The two gunships were > firing at 10ftx10ft targets at 1/2 a mile away. Out of the 32 > [Rockets] fired, no more than 4 hit the targets. Out of the rest > fired, most missed by a large margin. When a gunship would fire two at > once, one would hit about 100ft in front of the gunship and the other > would head towards the target. The 20mm gun did no better. It may not be generally known that the rockets were originally intended to be interim weapons, until the TOW was fitted to the Cobra. Rockets have continued to be used on the Cobra, however. The rockets are tube launched, fin stabilized weapons, originally intended to be launched from fixed wing aircraft. As such, they were launched into a head-wind. Now consider the launch environment from a rotary wing aircraft. Most engagements (particularly the ones at the demonstration last weekend) are from the hover. Read that as little or no headwind, and _lots_ of downdraft. As soon as the rocket warhead clears the tube, it immediately encounters a _significant_ downward force, causing an initial downward deflection in the flight attitude. As a result, as the fins reach their deployment position (leaving the tube), the rocket is not in the as-designed attitude, but is rather being forced against the bottom of the tube. This attitude is known to have caused some fins to improperly deploy. Combine the significant downward force on the rocket with loss of proper fin stabilization and it is little wonder that they are _area_ weapons from a helicopter. #include <std_disclaimer.h>