|
To view this page ensure that Adobe Flash Player version 9.0.124 or greater is installed. Policy Issues Regarding Airspace Restrictions. Besides these specific objections to security-related flight restrictions, many aviation interests and homeland security specialists have raised broader policy questions about the effectiveness of these various airspace restrictions and special operating procedures, noting that enforcing airspace restrictions is costly and resource intensive and providing protection to defend sites against aerial attacks is an even greater challenge. The resource requirements and associated costs for monitoring restricted airspace and providing airspace protection around critical sites raise policy questions regarding the appropriate balancing of these measures with efforts to address other homeland security threats, and the effect of these measures on air commerce and the freedom of movement by air. Surveillance and Monitoring of Restricted Airspace. Surveillance and monitoring capabilities present a significant challenge for protecting airspace. This is, in part, because detailed information on specific GA aircraft is not provided to air traffic controllers and airspace monitors unless the aircraft is transmitting a unique identifying code to air traffic radar sites. Under the current radar system, providing GA aircraft with unique identifiers and tracking all GA aircraft could, at times, prove overwhelming for air traffic controllers. Under present day air traffic control procedures, pilots must file flight plans, receive unique identifier codes to transmit, and make radio calls to air traffic controllers to establish “radar contact”allowing controllers to identify and track a specific flight. Under normal circumstances in clear weather, many flights never file a flight plan nor contact air traffic controllers 92 See, e.g., Aircraft Owners and Pilots Association. Members of Congress Join AOPA Outcry Over Presidential Movement TFRs. Frederick, MD; May 16, 2003. because they are not required to do so. But, to operate inside certain restricted airspace like the Washington, DC ADIZ, pilots must follow the aforementioned procedures for filing flight plans, transmitting unique identifying codes, and communicating with air traffic controllers – procedures that are often workload intensive for both pilots and controllers. Technologies may provide a solution that could ease pilot and controller workload associated with these transactions. For example, Mode S transponders are capable of automatically relaying detailed aircraft identifier information to air traffic radars, but most smaller GA aircraft do not have this technology and it is expensive to install. Similarly, emerging technology called Automated Dependent Surveillance - Broadcast (ADS-B) can transmit detailed aircraft information to ground stations and other aircraft, but this new technology is only beginning to become available and surveillance capability is not yet available in all parts of the United States. While ADS-B shows significant promise for improving safety as well as security, the FAA is still reviewing its investment strategy in this technology. In the meantime, surveillance of GA aircraft must rely on current radar capabilities, involving close coordination between pilots and air traffic controllers. This imposes additional workload on both pilots and controllers. This increased workload has a direct bearing on FAA resources. For example, the FAA estimates that making the Air Defense Identification Zone (ADIZ) around Washington, DC permanent will cost about $11 million per year, mostly linked to increased labor costs associated with processing flight plans and providing air traffic services to aircraft operating under visual flight rules (VFR) that would otherwise present little or no impact on the air traffic control system.93 中国通航网 www.ga.cn 通航翻译 www.aviation.cn 本文链接地址：Securing General Aviation 通用航空安保(52) |
