|
25-02-2013, 22:26
|
|
|
חבר מתאריך: 13.11.04
הודעות: 16,823
|
|
כתבה מעניינת על מערכות ההגנה השונות למטוסי נוסעים
בתגובה להודעה מספר 1 שנכתבה על ידי יוסי בכינור שמתחילה ב "ניסוי ישראלי מוצלח למיגון מטוסים מטילי כתף"
מתוך GUARDIAN, מגזין ה CT של המטות המשולבים
Raising the focus in man portable defensive systems
http://www.jcs.mil//content/files/2...ring _2011.pdf
אנקדוטות מעניינות
An estimated 500,000–700,000 MANPADs exist throughout the world, most commonly
the American Stinger and the Russian Strela and Igla The Strela’s most common variants are the SA-7 Grail and SA-14 Gremlin.[/B] Russian SA-7s and other missiles were found in Taliban caves during US operations in Afghanistan. Because of the number of sites that manufacture cheap copies, the SA-7 is the most prevalent threat: An SA-7 can be bought for as little as $5,000. Bulgaria, China, Egypt, Hungary, North Korea, and Pakistan all manufacture SA-7s. MANPADs stored in factory conditions have long shelf lives (some 22 years or more), although the launcher’s battery requires frequent replacement. With proper missile storage, replacement batteries, and training, any of the more than 30 groups thought to have MANPADs could successfully strike an airliner
In Baghdad, on 22 November 2003, two SA-14 Gremlin missiles were fired on a German DHL A300B4 aircraft that was flying at around 8,000 feet
Three methods will lower the chance of a successful MANPAD attack: (1) Minimize weapon availability, (2) isolate potential attack areas, and (3) take missile countermeasures. A comprehensive defense requires each of these methods to be addressed, although only postlaunch missile countermeasures, or counterMANPADs (C-MANPADs), could save lives once a missile is fired
Examining these patterns at Los Angeles International Airport, an SA-7 could be fired
from anywhere inside 870 square miles, a range that increases to 4,600 square miles for an SA-18. One bright spot is that many airports are near bodies of water (to make use of regular wind patterns, to mitigate flight noise, and to reduce potential crash damage). Although water also aids terrorists by providing a clear line of sight, a water exclusion zone can be invoked. This zone can then be patrolled and monitored for suspicious activity to reduce attacks
Countermeasures fall into three categories: flares, laser jammers, and high-energy lasers (HELs). Flares defend against first- and second-generation missiles by producing a heat signature that overwhelms the missile’s infrared guidance sensor. The main benefits
of flares are their immediate availability and strong performance against older (and more widely proliferated) missiles such as the SA-7. Laser jammers, also known as directed infrared countermeasures (DIRCMs), work well against early missiles by using a directed beam to overwhelm and then divert a missile. Laser jammers are a more appropriate defense because commercial aircraft cannot be expected to perform the highly evasive maneuvers needed to maximize the effectiveness of flares; however, because under mounted laser jammers fire downward, they require strong warning systems to avoid damage to personnel on the ground. Jammers are also unable to protect against command-guided missiles
Northrop Grumman’s Hornet HEL is palletized but has a limited range of around five
kilometers; multiple Hornets would be required to cover flight paths. HELs have two major drawbacks: (1) they are still in development (estimated to be at least 3 years from production) and (2) they involve classified systems, which would constrain them to limited deployments, especially to high-threat foreign airports
Of these options, laser jammers provide the best overall defense. They are designed to protect against the most likely type of missile. Although their ability to engage multiple missiles is not instant because of slew time, it is unlikely that terrorists would be able to fire multiple shots simultaneously; such a complex barrage would only occur from an advanced multiple-missile launcher system. Two leading laser jammer systems are BAE’s JETEYE and Northrop Grumman’s Guardian, both of which have been tested onboard commercial airliners. The 2008 testing involved attaching these systems to actual passenger aircraft to determine operational and cost impacts. American Airlines, which tested them on its Boeing 767-200s, is “not in favor” of these C-MANPAD systems due to the expected costs and lost profits
Cost is the biggest detraction of C-MANPADs. Commercial airlines are struggling financially, and adding more costs may increase burdens unnecessarily for a rare threat. It would cost an estimated $11 billion to install laser jammers on the approximately 6,800
commercial aircraft, including research and development and manufacturing costs.
The life cycle costs are estimated to be $40 billion over 10 years (including $2.1 billion per year for operations and support) The airline industry denounces these programs as a “vendor intent in selling C-MANPADs” and estimates the added operating cost at $365 per flight, subtracted from their claimed best-case profit of $600 per flight
|
|