WASHINGTON — The House and Senate versions of the 2011 defense authorization bill are generally supportive of missile defense and include measures designed to strengthen oversight of the planned European shield and ensure a smooth transition from the current Standard Missile 3 (SM-3) interceptor to a more capable variant.

The SM-3 is a key element of U.S. President Barack Obama’s new plan for defending European countries and deployed U.S. forces against attacks by medium- and intermediate-range ballistic missiles. The SM-3 is launched from U.S. Navy ships equipped with the Aegis Ballistic Missile Defense system, but plans call for developing a land-based version of the system to be deployed on European soil, and various upgrades to the interceptor are in the works.

The Pentagon in February requested $8.4 billion for U.S. Missile Defense Agency (MDA) programs and another $1.5 billion for Army missile defense programs in 2011. The House on May 28 passed an authorization bill that adds $227 million to the overall MDA request. The Senate version of the bill, which has cleared the Senate Armed Services Committee and is scheduled to come up for a vote on the Senate floor in July, recommends funding MDA at the level requested by the White House.

The House and Senate appropriations committees have yet to mark up their versions of the 2011 defense spending bill.

Both the House and Senate authorization bills recommended that an additional $133.6 million be provided for the Army’s Patriot Advanced Capability-3 program in response to an unfunded requirement from Army Chief of Staff Gen. George Casey. The additional money would enable more Patriot missiles to be repaired and recertified and provide for more Patriot launching station kits, according to language in the report accompanying the Senate bill. The Army requested $57.2 million for Patriot procurement next year.

But the main focus of the policy language in the authorization bills was the European shield. Last year, the Obama administration scrapped previous plans to defend Europe using a smaller variant of the interceptors being deployed in California and Alaska to defend U.S. territory. Obama’s so-called Phased Adaptive Approach would place missile defense radar in southern Europe starting next year and deploy U.S. Navy Aegis ships equipped with SM-3 Block 1A interceptors to European waters. A land-based version of the system — including SM-3 Block 1B interceptors deployed in Poland and Romania — would be in place by 2015. To defend against longer-range ballistic missiles, the United States is developing the SM-3 Block 2A and Block 2B missiles for deployment toward the end of the decade.

Both the House and Senate armed services committees support the Phased Adaptive Approach, but with provisos. The House bill would limit the availability of funds for construction and deployment of missile defense systems in Europe until the host nation has signed and ratified a hosting agreement, and 45 days have passed since an independent assessment of alternative missile defense systems for Europe has been delivered to Congress. The House also fenced off 5 percent of 2011 funding until the secretary of defense submits a report certifying the European missile defense system is effective and has been tested under operationally realistic conditions. The Aegis Ballistic Missile Defense system has a flight test record of 20 intercepts in 24 attempts since 2002.

Both the House and Senate authorizers are concerned about the Pentagon’s plan to transition production from the SM-3 Block 1A to the more capable Block 1B. The Pentagon requested $94.1 million in 2011 to buy the first eight Block 1B interceptors, and plans to request $701.9 million in 2012 for another 66. Language in the report accompanying the House bill noted that production of the Block 1B missile will begin this year, even though the missile will not make its first flight test until early 2011. In order to stabilize SM-3 production levels, the House recommended adding $50 million to increase the number of Block 1B missiles bought in 2011, assuming the first flight test is successful.

The Senate panel is also concerned with plans to sharply increase SM-3 production from 2011 to 2012, but does not explicitly recommend any additional funding next year. Language in the report accompanying the Senate bill says MDA should consider risk mitigation options, including budgeting some research and development funding to cope with potential production challenges. Furthermore, the report said, some SM-3 Block 1A components will soon be obsolete, and if there is a development problem with the Block 1B missile, a situation could arise in which neither is in production. The Senate bill would direct the Pentagon to ensure SM-3 Block 1A component suppliers are supported until the Block 1B is proven, suggesting 2010 funds be reprogrammed for this measure.

The Senate also is concerned that the SM-3 Block 2B, which is being designed to defeat intercontinental ballistic missiles, will be limited to land-based deployments because of the fuels it will use. The Senate bill would direct MDA to conduct an analysis of alternatives that would allow the Block 2B missile to be deployed on ships. The analysis would be due to Congress by May 2011.

Meanwhile, the House recommended adding funds for the Airborne Laser program, which has been relegated to a technology development and demonstration platform. The MDA’s budget request included $96.7 million for directed energy research, and the House bill recommended adding $50 million to support increased research, development and testing of these technologies, “including using [the Airborne Laser] as a test platform.”

Both the Senate and House bills recommend providing additional funds for cooperative U.S.-Israeli missile defense programs. The MDA requested $46.7 million to continue development of the David’s Sling Weapon System; the House bill recommended adding $38 million, and the Senate bill would add $25 million. The House recommended adding $8 million to the $50.8 million request for the Arrow-3 interceptor and $42 million to the $12.2 million request for Arrow Weapon System improvements.