PART I

EXPLANATORY NOTE REGARDING THIS ANNUAL REPORT

In March 2015, we changed our fiscal year from the period beginning on April 1 and ending on March 31 to the period beginning on January 1 and ending on December 31 . We refer in this report to the nine-month period beginning on April 1, 2015 and ending on December 31, 2015 as the "2015 transition period." All fiscal years after December 31, 2015 are for the calendar year ended December 31. We sometimes refer in this report to the period beginning January 1, 2017 and ending on December 31, 2017 as "calendar 2017" or "2017" and the period beginning on January 1, 2016 and ending on December 31, 2016 as "calendar 2016" or "2016." We refer in this report to the period beginning on April 1, 2014 and ending on March 31, 2015 as “fiscal 2015” and the period beginning on April 1, 2013 and ending on March 31, 2014 as “fiscal 2014.”

Sales; income from continuing operations, before interest, income taxes and noncontrolling interest; and other financial data for each segment for the year ended December 31, 2017, the year ended December 31, 2016 and the nine months ended December 31, 2015, respectively, are set forth in Note 18, Operating Segment Information , to the consolidated financial statements included in Part II, Item 8, "Financial Statements and Supplementary Data" of this report.

Flight Systems Group

Flight Systems Group develops launch vehicles that are used as small- and medium-class space launch vehicles to place satellites into earth orbit and escape trajectories, interceptor and target vehicles for missile defense systems and suborbital launch vehicles that place payloads into a variety of high-altitude trajectories. The Group also develops and produces medium- and large-class rocket propulsion systems for human and cargo launch vehicles, strategic missiles, missile defense interceptors and target vehicles. Additionally, the Group operates in the military and commercial aircraft and launch structures markets.

The following is a description of the divisions within Flight Systems Group :

Launch Vehicles Division

The Launch Vehicles division includes both small- and medium-class rockets for government, civil and commercial payloads. Our innovative Pegasus ^® rocket is launched from our "Stargazer" L-1011 carrier aircraft and has proven to be the small space-launch workhorse for U.S. Government and commercial customers. Our Taurus launch vehicle combines our Pegasus upper-stage motors with a commercially-provided first stage propulsion system for increased performance. Our Minotaur I, IV and V rockets combine decommissioned Minuteman and Peacekeeper rocket motors with our proven upper stage motors, avionics and fairings to provide increased lifting capacity for government-sponsored payloads.

The division's Antares rocket is a two-stage vehicle (with optional third stage) that provides low-earth orbit launch capability for payloads weighing up to 7,000 kg. The Antares rocket has been used in the execution of our Commercial Resupply Services ("CRS") contract with the National Aeronautics and Space Administration ("NASA") to deliver cargo to the ISS. The Antares design has been upgraded with RD-181 first stage engines to provide greater payload performance and increased reliability, and the reconfigured Antares rocket successfully flew in 2016 and 2017, with two launches scheduled in 2018, both in connection with the CRS-1 contract. Additional missions through 2024 under the CRS-1 contract and the follow-on CRS-2 contract are planned.

The division also is an industry-leading provider of suborbital launch vehicles for the nation's missile defense systems for the U.S. Missile Defense Agency, the U.S. Air Force, Army and Navy, and allied nations. Additionally, the division is the sole provider of interceptor boosters for the U.S. Missile Defense Agency's Ground-based Midcourse Defense ("GMD") system designed to intercept and destroy long-range enemy missiles. We are also a primary supplier of highly-reliable target vehicles that serve as "threat simulators" to provide high-fidelity facsimiles of enemy missile threats in the testing and verification of missile defense systems.

Propulsion Systems Division

The Propulsion Systems division is the development and production center for solid rocket motors for NASA's current and planned human spaceflight programs, including the Space Launch System ("SLS") heavy lift vehicle and the launch abort system motor for the Orion ^® crew capsule that is designed to safely pull the crew capsule away from the launch vehicle in the event of an emergency during launch.

The division also produces medium-class solid rocket motors for the U.S. Navy's Trident II Fleet Ballistic Missile program and conducts solid rocket propulsion sustainment activities for the U.S. Air Force's Minuteman III Intercontinental Ballistic Missile. These two programs provide the backbone of the United States' strategic deterrence program. Additional solid rocket motors being produced by the division include Graphite Epoxy Motors for the Delta IV, Atlas and Vulcan, Orion motors for our Pegasus and Minotaur launch vehicles and U.S. Missile Defense Agency targets, and CASTOR ^® motors for our Antares rocket and Taurus rocket. The division supplies Orion motors for all three stages of the GMD system, as well as other Orbital ATK launch vehicles and is in the process of developing the Next Generation Launcher for the U.S. Government. In addition, the division produces advanced flares and decoys that provide illumination for search and rescue missions and countermeasures against missile attacks.

Aerospace Structures Division

The Aerospace Structures division is a provider of advanced composite aircraft structures for military and commercial aircraft manufacturers, using highly automated composite fabrication techniques, including automated fiber placement and stiffener forming processes. The division provides a wide variety of composite parts for the F-35 Lightning II Joint Strike Fighter, a fifth-generation fighter aircraft for the U.S. military and its allies. It also provides composite radomes and apertures for a number of military aircraft and provides wing stiffeners for the A400M military transport aircraft. The division provides very large fiber-placed and hand lay-up structures for the Antares, Atlas and Delta launch vehicles, and filament-wound composite cases for solid rocket motors and composite overwrapped pressure vessels.

The division has a commercial aerospace composites center of excellence facility in Clearfield, Utah to support its commercial aerospace customers, including Airbus, Rolls Royce and Boeing. The division is under contract to produce the majority of the composite fuselage stringers and frames for the Airbus A350 XWB wide-body passenger jetliner. Additional major commercial programs include a contract with Rolls Royce to produce the aft fan case for the Trent XWB engine, which is used to power the Airbus A350 aircraft, and a contract to produce composite frames for the Boeing 787-9 and 787-10 commercial aircraft.

Defense Systems Group

Defense Systems Group develops and produces small-, medium- and large-caliber ammunition, precision weapons and munitions, high-performance gun systems, and propellant and energetic materials. It operates the Lake City Army Ammunition Plant in Independence, Missouri and a Naval Sea Systems Command facility in Rocket Center, West Virginia. Defense Systems Group is also a leader in tactical solid rocket motor development and production for a variety of air-, sea- and land-based missile systems. The Group serves a variety of domestic and international customers in the defense and security markets in a prime contractor, partner or supplier role.  Defense Systems Group also provides propulsion control systems that support U.S. Missile Defense Agency and NASA programs, airborne missile warning systems, advanced fuzes and defense electronics.  The Group produces the U.S. Navy's Advanced Anti-Radiation Guided Missile ("AARGM") and has developed advanced air-breathing propulsion systems and special-mission aircraft for defense applications.

The following is a description of the divisions within Defense Systems Group :

Missile Products Division

The Missile Products division provides customers with high-performance tactical solid rocket motor propulsion for a variety of surface- and air-launched missile systems including Hellfire, Maverick, Advanced Medium-Range Air-to-Air Missile and Sidewinder. The division also produces warheads, fuzing and sensors for various artillery, mortar, grenade and air-dropped weapons, including the Hard Target Void Sensing Fuze. The division produces metal components for various medium-caliber ammunition and 120mm tank ammunition, and also produces specialty composite and ceramic structures used on military platforms. The division provides customers with the third-stage

propulsion on the Standard Missile defense interceptor.  Additional capabilities include the STAR™ family of satellite orbit insertion motors, high performance rocket boosters and advanced air-breathing propulsion for platforms designed for Mach 3+ flight. It also continues to operate our New River Energetics facility located on the Radford Army Ammunition Plant in Radford, Virginia, which provides load, assembly and pack of medium caliber munitions; and propellants and powders for the canister and commercial markets, individual re-loaders and ammunition manufacturers.

Armament Systems Division

The Armament Systems division is home to our precision weapons and medium- and large-caliber ammunition programs, including advanced precision munition programs. The division is under contract to develop the U.S. Army's new multi-purpose tank round and currently produces the Precision Guidance Kit for 155mm artillery. The division also produces the family of medium-caliber Bushmaster ^® chain guns and is a global systems designer and producer of medium-caliber ammunition for integrated gun systems. These gun systems are used on a variety of ground combat vehicles, helicopters and naval vessels, including the Bradley Fighting Vehicle, the Light Armored Vehicle, coastal patrol craft and Apache helicopters. New products include a link-fed variant of the Apache gun system for ground and naval applications. Armament Systems also leads Defense Systems Group 's international co-production efforts and provides munitions support to allied nations.

Defense Electronic s Division

The Defense Electronic s division provides customers with advanced capabilities for offensive and defensive electronic warfare and specializes in weaponized airborne intelligence, surveillance and reconnaissance platforms and advanced anti-radiation homing missile systems, special-mission aircraft, missile warning systems and mission support equipment. Key programs include the AARGM missile used by the U.S. Navy and North Atlantic Treaty Organization militaries, and the AAR-47 missile warning system used by U.S. and allied fixed- and rotor-wing aircraft to defeat incoming missile threats. The division also provides special-mission aircraft that integrate sensors, fire control software, gun systems and air-to-ground weapons capability for use in counterinsurgency, border/coastal surveillance and security missions.

Small Caliber Systems Division

The Small Caliber Systems division via operating the Lake City Army Ammunition Plant is the largest producer of small-caliber ammunition in the U.S., covering 5.56, 7.62 and .50 caliber rounds. The division also provides non-NATO ammunition to the U.S. Army for use by allied forces. The division also provides commercial ammunition to Vista Outdoor. Since 2000, the Company has operated and modernized the Lake City Army Ammunition Plant.

Space Systems Group

Space Systems Group offers a broad portfolio of products for commercial, military, scientific and international customers. The Group develops and produces small- and medium- class satellites that are used to enable global and regional communications and broadcasting, conduct space-related scientific research and perform activities related to national security. In addition, the Space Systems Group develops and produces human-rated space systems for earth orbit and deep-space exploration, including delivering cargo to the ISS. This Group is also a provider of spacecraft components and subsystems as well as specialized engineering and operations services to U.S. Government agencies.

The following is a description of the divisions within Space Systems Group :

Satellite Systems Division

The Satellite Systems division designs and produces small- and medium- class satellites used for various activities including: national security space programs, geosynchronous ("GEO") satellites used for global and regional communications/broadcasting, commercial imaging and remote sensing satellites. The division also conducts space-related scientific research, including astrophysics, earth science/remote sensing and heliophysics, interplanetary and other deep-space exploration missions, including the demonstration of new space technologies. In addition, the division designs and manufacturers satellite buses tailored to accommodate a variety of payloads and hosted payloads for various orbits or interplanetary missions.

Advanced Programs Division

The Advanced Programs division consists of two main business areas: human space systems and space robotics and logistics. In the human space systems business area, the division provides human-rated space systems for low-earth orbit and deep-space exploration, including cargo missions to the ISS under the CRS-1 and CRS-2 programs using the Cygnus spacecraft. The division is also working in partnership with NASA on various programs, including the Deep Space Gateway, Power Propulsion Element, as well as NextSTEP-2 which focuses on the development of deep space habitat prototypes. In the space robotics and logistics business area, the division is working to develop and build Mission Extension Vehicles to provide in-orbit GEO satellite life extension. Additional areas of focus include space robotics capabilities development to support areas such as in-orbit satellite assembly and repair.

Space Components Division

The Space Components division is a major supplier of satellite mechanical components and structural assemblies for a wide variety of commercial, civil and defense spacecraft. As a leader in the industry, we believe that products manufactured by the division have flown aboard virtually every U.S. satellite built in the last 20 years. The division has strong market positions in spacecraft composite primary and secondary structures, satellite fuel and oxidizer tanks, precision payload structures, solar power arrays, deployable structures and thermal control systems.

Technical Services Division

The Technical Services division provides a full spectrum of cost-effective engineering, manufacturing and program management services to NASA and other civil government and military space agencies. The division also manages high-profile NASA science programs, including its scientific sounding rocket and high altitude balloon activities.

Customers

Our sales have come primarily from contracts with agencies of the U.S. Government and its prime contractors and subcontractors, and from major domestic and international commercial satellite operators, international customers including foreign military sales contracted through the U.S. Government and aircraft manufacturers. As the various U.S. Government customers, including the U.S. Navy, U.S. Army, NASA and the U.S. Air Force, make independent purchasing decisions, we do not generally regard the U.S. Government as one customer. Instead, we view each agency as a separate customer.

Sales by customer, as a percentage of total sales, were as follows:

Sales to the U.S. Government and its prime contractors were as follows (in millions) :

The Company's CRS contracts with NASA, which are reported within its Flight Systems Group and Space Systems Group, comprised 9%, 13% and 10% of total sales in the years ended December 31, 2017 and 2016 and in the 2015 transition period, respectively. No other single contract accounted for more than 10% of the Company's sales in the years ended December 31, 2017 and 2016 or in the 2015 transition period.

Other than the U.S. Government customers listed above, no single customer accounted for more than 10% of our sales in the year ended December 31, 2017 , the year ended December 31, 2016 or in the 2015 transition period.

International sales were as follows (in millions) :

Sales to foreign governments and other international customers may require approval by the U.S. Department of Defense ("DoD") and the U.S. Department of State or the U.S. Department of Commerce. Our products are sold to U.S. allies directly, as well as through the U.S. Government. During the year ended December 31, 2017 , approximately 20% of these sales were in Flight Systems Group , 66% were in Defense Systems Group , and 14% were in Space Systems Group . No sales to an individual country outside the United States accounted for more than 5% of our sales in the year ended December 31, 2017 .

Backlog

Firm backlog is the estimated value of contracts for which orders have been recorded, but for which revenue has not yet been recognized. The total amount of firm backlog was approximately $10.2 billion at December 31, 2017 and $9.3 billion at December 31, 2016 . Approximately $3.4 billion of firm backlog was not yet funded at December 31, 2017 . We expect that approximately 43% of the December 31, 2017 firm backlog will be recognized as revenue in calendar year 2018.

Total backlog, which includes firm backlog plus the value of unexercised options, was approximately $16.0 billion at December 31, 2017 and $14.4 billion at December 31, 2016 .

Seasonality

Our business is not seasonal.

Competition

We compete against other U.S. and foreign prime contractors and subcontractors, many of which have substantially more resources to deploy than we do in the pursuit of government and industry contracts. Our ability to compete successfully in this environment depends on a number of factors, including the creativity and effectiveness of research and development programs, our ability to offer better program performance than our competitors and/or at a lower cost, our readiness with respect to facilities, equipment and personnel to undertake the programs for which we compete, and our past performance and demonstrated capabilities.

Additional information on the risks related to competition can be found in Item 1A, "Risk Factors" of this report.

We generally face competition from a number of competitors in each business area, although no single competitor competes along all of our segments. Our principal competitors in each of our segments are as follows:

Flight Systems Group :    Aerojet-Rocketdyne Holdings, Inc.; Arianespace SA; Coleman Aerospace, a division of Aerojet-Rocketdyne Holdings, Inc.; GKN Aerospace Company; Lockheed Martin Corporation; Space Exploration Technologies Corporation; Spirit Aerosystems Company; United Launch Alliance (a joint venture between Lockheed Martin Corporation and The Boeing Company); and Vought Aircraft, a division of Triumph Aerostructures.

Defense Systems Group :   Aerojet-Rocketdyne Holdings, Inc.; BAE Systems; Chemring Group; General Dynamics Corporation; Lockheed Martin Corporation; Nammo AS; Nexter SA; Winchester Ammunition Division of Olin Corporation; Raytheon Company; Rheinmetall AG; and various other international competitors.

Space Systems Group : Airbus Defense and Space; Ball Aerospace and Technologies Corp.; Lockheed Martin Corporation; Maxar Technologies; Millenium Space Systems; Sierra Nevada Corporation; Space Exploration Technologies Corporation; Thales Alenia Space; and The Boeing Company.

Research and Development

We conduct extensive research and development ("R&D") activities. Company-funded R&D is primarily for the improvement of current products and for development of next-generation technology. Customer-funded R&D is comprised primarily of activities we conduct under contracts with the U.S. Government and its prime contractors. R&D expenditures were as follows (in millions) :

Raw Materials and Components

We use a broad range of raw materials in manufacturing our products, including aluminum, steel, copper, lead, ammonium perchlorate, graphite fiber, epoxy resins, zinc and adhesives. We monitor the sources from which we purchase raw materials in an attempt to ensure there are adequate supplies to support our operations. We monitor the price of materials, particularly commodity metals like copper, which have fluctuated dramatically over the past several years.

We also use sub-assemblies and instruments in our products and obtain parts and equipment that are used in the production of our products or in the provision of our services from domestic and foreign suppliers and the U.S. Government. Generally, we have not experienced material difficulty in obtaining product components or necessary parts and equipment, and we believe that alternatives to our existing sources of supply are available in most cases.

We procure materials and components from a variety of sources. In the case of our U.S. Government contracts, we are often required to purchase from sources approved by the DoD. When our suppliers choose to eliminate certain materials or components we require from their product offering, we attempt to qualify other suppliers or replacement materials to ensure there are no disruptions to our operations.

We rely upon sole-source suppliers for many of our satellite and launch vehicle components, including our liquid-propellant rocket engines and cores. The inability of our current suppliers to provide us with key components could result in significant contract delays, cost increases and loss of revenues due to the time, resources and effort that would be required to develop or adapt other engines or components for use in our products.

Additional information on the risks related to raw materials and components can be found in Item 1A, "Risk Factors" of this report.

Intellectual Property

Although we manufacture various products covered by patents, we do not believe that any single existing patent, license or group of patents is material to our success. We believe that unpatented research, development and engineering skills also make an important contribution to our business. The U.S. Government typically receives royalty-free licenses to inventions made under U.S. Government contracts. Consistent with our policy to protect proprietary information from unauthorized disclosure, we ordinarily require employees to sign confidentiality agreements as a condition of employment.

As many of our products are complex and involve patented and other proprietary technologies, we face a risk of claims alleging that we have infringed upon third-party intellectual property rights. Such claims could result in costly and time-consuming litigation, the invalidation of our intellectual property rights and/or increased licensing costs.

Regulatory Matters

U.S. Governmental Contracts

We are subject to the procurement policies and procedures set forth in the Federal Acquisition Regulation ("FAR"). The FAR governs all aspects of government contracting, including competition and acquisition planning; contracting methods and contract types; contractor qualifications; and acquisition procedures. Every U.S. Government contract contains a list of FAR provisions that must be complied with in order for the contract to be awarded. The FAR provides for regular audits and reviews of contract procurement, performance and administration. Failure to comply with the provisions of the FAR could result in contract termination.

The U.S. Government may terminate its contracts with its suppliers, either for convenience or in the event of a default as a result of our failure to perform under the applicable contract. If a cost-plus contract is terminated for convenience, we are entitled to reimbursement of our approved costs and payment of a total fee proportionate to the percentage of the work completed under the contract. If a fixed-price contract is terminated for convenience, we are entitled to payment for items delivered to and accepted by the U.S. Government, and fair compensation for work performed plus the costs of settling and paying claims by terminated subcontractors, other settlement expenses and a reasonable profit on the costs incurred or committed. If a contract termination is for default, we are paid an amount agreed upon for completed and partially completed products and services accepted by the U.S. Government, and may be liable to the U.S. Government for repayment of any advance payments and progress payments related to the terminated portions of the contract, as well as excess costs incurred by the U.S. Government in procuring undelivered items from another source.

Additional information on the risks related to government contracts can be found in Item 1A,"Risk Factors" of this report.

Laws Relating to Import-Export

We also must comply with U.S. and foreign laws governing the export of munitions and other controlled products and commodities. These include regulations relating to import-export control, exchange controls, the Foreign Corrupt Practices Act and the anti-boycott provisions of the U.S. Export Administration Act.

U.S. Government Contract Security Restrictions

Certain programs with the U.S. Government are prohibited by the customer from being publicly discussed. The consolidated financial statements and financial information in this Annual Report on Form 10-K reflect the operating results of our entire company, including restricted programs, under accounting principles generally accepted in the United States of America (GAAP).

Environmental

Our operations are subject to a number of federal, state and local environmental laws and regulations, as well as applicable foreign laws and regulations that govern the discharge, treatment, storage, remediation and disposal of certain materials and wastes, and restoration of damages to the environment. Compliance with these laws and regulations is a responsibility we take seriously. We believe that forward-looking, proper and cost-effective management of air, land and water resources is vital to the long-term success of our business. Our environmental policy identifies key objectives for implementing this commitment throughout our operations. Additional information on the risks related to environmental matters can be found in Item 1A, "Risk Factors" of this report.

Employees

At December 31, 2017 , we had approximately 13,900 employees. We have union-represented employees at five locations, comprising less than 20% of our total workforce. One location has two separate bargaining units, each with its own collective bargaining agreement (“CBA”). The Company’s current CBAs expire in 2018, 2019, 2021, and 2022.

Executive Officers

The following table sets forth certain information with respect to our executive officers at December 31, 2017 :

Each of the above individuals serves at the pleasure of the Board of Directors. No family relationship exists among any of the executive officers or among any of them and our directors. There are no outstanding loans from our company to any of these individuals. Information regarding the employment history (in each case with our Company unless otherwise indicated) of each of the executive officers is set forth below.

David W. Thompson has served in his present position since the Orbital-ATK Merger on February 9, 2015. Mr. Thompson has also been a director of our Company since the Orbital-ATK Merger. He co-founded Orbital and served as Chairman of the Board and Chief Executive Officer of Orbital from 1982 until the Orbital-ATK Merger. From 1982 until October 1999, he also served as President of Orbital, a role he resumed in mid-2011. Prior to founding Orbital, Mr. Thompson was employed by Hughes Electronics Corporation as special assistant to the President of its Missile Systems Group and by NASA at the Marshall Space Flight Center as a project manager and engineer, and also worked on the Space Shuttle's autopilot design at the Charles Stark Draper Laboratory. Mr. Thompson is an Honorary Fellow of the American Institute of Aeronautics and Astronautics, a Fellow of the American Astronautical Society and the Royal Aeronautical Society, and is a member of the U.S. National Academy

of Engineering. He also serves as a member of the Board of Trustees of the California Institute of Technology and the Carnegie Institution for Science.

Blake E. Larson has served in his present position since the Orbital-ATK Merger on February 9, 2015. From April 2010 until February 9, 2015, he served as our Senior Vice President and President, Aerospace Group. From 2009 to March 2010, he was Senior Vice President and President, Space Systems. From 2008 to 2009, he was Executive Vice President, Space Systems, and also General Manager, Spacecraft Systems from August 2008 to January 2009. From 2006 to 2008, he was Executive Vice President of Mission Systems Group. Prior to that, Mr. Larson held a variety of key leadership positions in operations of several businesses within our aerospace and defense portfolio.

Garrett E. Pierce has served in his present position since the Orbital-ATK Merger on February 9, 2015. He was Vice Chairman and Chief Financial Officer of Orbital from 2002 until the Orbital-ATK Merger, and was Executive Vice President and Chief Financial Officer of Orbital from 2000 to 2002. From 1996 until 2000, he was Executive Vice President and Chief Financial Officer of Sensormatic Electronics Corp., a supplier of electronic security systems, where he was also named Chief Administrative Officer in July 1998. Prior to joining Sensormatic, Mr. Pierce was the Executive Vice President and Chief Financial Officer of California Microwave, Inc., a supplier of microwave, radio frequency, and satellite systems and products for communications and wireless networks. From 1980 to 1993, Mr. Pierce was employed by Materials Research Corporation, a provider of thin film equipment and high purity materials to the semiconductor, telecommunications and media storage industries, where he progressed from Chief Financial Officer to President and Chief Executive Officer. Materials Research Corporation was acquired by Sony Corporation in 1989. From 1972 to 1980, Mr. Pierce held various management positions with The Signal Companies. Mr. Pierce is a Director of Kulicke and Soffa Industries, Inc.

Antonio L. Elias has served in his present position since the Orbital-ATK Merger on February 9, 2015. He was Executive Vice President and Chief Technical Officer of Orbital from September 2012 until the Orbital-ATK Merger. From October 2001 to September 2012, he served as Orbital's Executive Vice President and General Manager, Advanced Programs Group, and was Orbital's Senior Vice President and General Manager, Advanced Programs Group from 1997 to 2001. From 1996 until 1997, Dr. Elias served as Senior Vice President and Chief Technical Officer of Orbital. From 1993 through 1995, he was Orbital's Senior Vice President for Advanced Projects, and was Orbital's Senior Vice President, Space Systems Division from 1990 to 1993. He was Vice President, Engineering of Orbital from 1989 to 1990 and was Orbital's Chief Engineer from 1986 to 1989. From 1980 to 1986, Dr. Elias was an Assistant Professor of Aeronautics and Astronautics at Massachusetts Institute of Technology. He was elected to the National Academy of Engineering in 2001.

Frank L. Culbertson, Jr. has served in his present position since the Orbital-ATK Merger on February 9, 2015. He was Orbital's Executive Vice President and General Manager, Advanced Programs Group from September 2012 until the Orbital-ATK Merger. From 2008 to 2012, he served as a Senior Vice President in Orbital's Advanced Program Group, where he headed human space systems efforts. Prior to joining Orbital, Mr. Culbertson was a Senior Vice President at Science Applications International Corporation from 2002 to 2008. Before entering the private sector, Mr. Culbertson served as a NASA astronaut for 18 years, flying three Space Shuttle missions, and began his career as a pilot in the U.S. Navy.

Michael A. Kahn has served in his present position since the Orbital-ATK Merger on February 9, 2015. From April 2012 until February 9, 2015, he served as our Senior Vice President and President, Defense Group. From August 2010 through March 2012, he was Senior Vice President and President, Missile Products Group. From 2009 to August 2010, he was Executive Vice President, Aerospace Systems. From 2008 to 2009, he was Vice President and General Manager, Launch Systems, and from 2001 to 2008, he was Vice President, Space Launch Systems. From 1997 to 2001, he was Vice President, Operations, and played a key role in the integration of Thiokol and ATK. From 1989 to 1997, he held a number of senior leadership positions across a variety of programs and operations of our company. Prior to that he was with Rockwell International, Rocketdyne Division, and held a number of positions across engineering, quality and reliability assurance, launch site operations and rocket engine testing.

Scott L. Lehr  has held his present position since July 1, 2015. From April 2015 through June 2015, he was Senior Vice President, Flight Systems Group. From April 2009 through March 2015, he served as Vice President and General Manager of Defense and Commercial Systems in the Aerospace Group.  From 2007 to 2009, he was Vice President, Operations, and from 2004 to 2007, he was Vice President, Air Force Programs within the Launch Systems Group. Prior to that, he held a number of senior leadership positions in engineering and program management as part of our propulsion business. He joined the company in 1984 and has more than 30 years of experience in the aerospace industry. 

Thomas E. McCabe has served in his present position since the Orbital-ATK Merger on February 9, 2015. He was Senior Vice President, General Counsel and Corporate Secretary of Orbital from January 2014 until the Orbital-ATK Merger. Before joining Orbital, he served from 2010 to 2014 as Senior Vice President, General Counsel and Secretary of Alion Science and Technology Corporation, a provider of advanced engineering and technology solutions. From 2008 to 2010, he served as Executive Vice President and General Counsel, and President of the Federal business of Braintech, Inc., which provided automated vision systems for industrial and military robots. Earlier in his career, he was Vice President and Deputy General Counsel of XM Satellite Radio from 2005 through its merger with Sirius Satellite Radio in 2008. He also served as President, CEO and a director of software provider MicroBanx Systems from 2001 to 2005, and President, CEO and a director of its parent company, COBIS Corporation, from 2004 to 2005. From 1992 to 2000, he was a senior executive at GRC International, Inc., a provider of advanced software and technology solutions, serving as Senior Vice President, General Counsel, Secretary and Director of Corporate Development through its sale to AT&T in 2000. He was an attorney in private practice from 1982 to 1991. He began his career as judicial clerk for Judge Charles R. Richey at the United States District Court for the District of Columbia from 1981 to 1982.

Christine A. Wolf has held her present position since joining the company in March 2011. She has more than 30 years of experience in the Human Resources field. Prior to joining the company, she was the Senior Vice President and Chief Human Resources Officer for Fannie Mae from 2008 to March 2011. Prior to that, she was the Chief Human Resources Officer for E*Trade from 2004 to 2008.

Available Information

Our reports filed with the Securities and Exchange Commission ("SEC") can be found on our Internet site at www.orbitalatk.com under the "Investors" heading free of charge. These include our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934. We make these reports available as soon as reasonably practicable after they are electronically filed with, or furnished to, the SEC.

You can also obtain these reports from the SEC's Public Reference Room, which is located at 100 F Street, NE, Washington, D.C. 20549. Information on the operation of the Public Reference Room is available by phone (1-800-SEC-0330) or on the Internet ( www.sec.gov ). This site contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC.

The content on any website referred to in this Form 10-K is not incorporated by reference into this Form 10-K unless expressly noted.