RQ-4 Global Hawk

A Global Hawk unmanned aerial vehicle lands at Nordholz Air Base, Germany, after a demonstration sortie. The vehicle returned to Edwards Air Force Base, Calif., on Nov. 7, 2003. (Northrup Grumman photo/Gene Yano)

MQ-9 Reaper

A MQ-9 Reaper flies above Creech Air Force Base, Nev., during a local training mission June 9, 2009. The 42nd Attack Squadron at Creech AFB operates the MQ-9. (U.S. Air Force photo/Paul Ridgeway)

MQ-9 Reaper

An MQ-9 Reaper unmanned aircraft prepares to land after a mission in support of Operation Enduring Freedom in Afghanistan. The Reaper has the ability to carry both precision-guided bombs and air-to-ground missiles. (U.S. Air Force photo/Staff Sgt. Brian Ferguson)

MQ-9 Reaper

A MQ-9 Reaper prepares to launch Feb. 28 from Creech Air Force Base, Nev.. The Reapers arrived at the base in March 2007. (U.S. Air Force photo/Lawrence Crespo)

MQ-9 Reaper

An MQ-9 Reaper unmanned aerial vehicle flies over the crowd during the Aviation Nation Air Show at Nellis Air Force Base, Nev., Nov. 10. This year's show commemorated 60 years of airpower during the Air Force's year-long 60th anniversary celebration. (U.S. Air Force photo/Master Sgt. Robert W. Valenca)

MQ-9 Reaper

A fully armed MQ-9 Reaper taxis down an Afghanistan runway Nov. 4. The Reaper has flown 49 combat sorties since it first began operating in Afghanistan Sept. 25. It completed its first combat strike Oct. 27, when it fired a Hellfire missile over Deh Rawod, Afghanistan. (U.S. Air Force photo/Staff Sgt. Brian Ferguson)

MQ-9 Reaper

An MQ-9 Reaper takes off on a mission in Afghanistan Oct. 1. The MQ-9 has nearly nine times the range, can fly twice as high and carries more munitions than the MQ-1 Predator. (Courtesy photo)

MQ-9 Reaper

Aircrews perform a preflight check on an MQ-9 Reaper before it takes off on a mission in Afghanistan Oct. 1. The Reaper is larger and more heavily-armed than the MQ-1 Predator and attacks time-sensitive targets with persistence and precision, to destroy or disable those targets. (Courtesy photo)

MQ-9 Reaper

A maintenance Airman inspects an MQ-9 Reaper in Afghanistan Oct. 1. Capable of striking enemy targets with on-board weapons, the Reaper has conducted close air support and intelligence, surveillance and reconnaissance missions. (Courtesy photo)

T-37 Tweet

After more than 50 years of dependable service, the T-37 Tweet has retired. The last seven T-37s in the Air Force inventory, including the two pictured here, took off one final time July 31 as part of the aircraft's retirement ceremony. (U.S. Air Force photo/Harry Toneman)

T-37 Tweet

The last seven T-37 Tweets in the Air Force inventory, including the two pictured here, took off one final time July 31 as part of the aircraft's retirement ceremony. Four of the aircraft will make the journey to the Aerospace Maintenance and Regeneration Group at Davis-Monthan Air Force Base, Ariz., while the final three will go to the Utah Test and Training Range in Utah. (U.S. Air Force photo/Harry Toneman)

T-37B Tweet

The last Randolph T-37B Tweet departs the flightline April 6 during the aircraft's official retirement ceremony from base. The Tweet served as the primary pilot instructor training aircraft from October 1965 to April 2007. (U.S. Air Force photo/Dave Terry)

T-37B Tweet

The T-37B Tweet is a twin-engine jet used for training student pilots in fundamentals of aircraft handling. It became part of the Air Force inventory in 1955. (U.S. Air Force photo)

T-37 Tweet

A T-37 Tweet aircraft from the 85th Fighter Training Squadron, Laughlin AFB, Texas, flies over Lake Amistad during a training mission. The T-37 Tweet is a twin-engine jet used for training undergraduate pilots, undergraduate navigator and tactical navigator students in fundamentals of aircraft handling, and instrument, formation and night flying. The twin engines and flying characteristics of the T-37 give student pilots the feel for handling the larger, faster T-38 Talon or T-1A Jayhawk later in the undergraduate pilot training course. The instructor and student sit side by side for more effective training. The cockpit has dual controls, ejection seats and a clamshell-type canopy that can be jettisoned. (Air Force photo by Staff Sgt. Andy Dunaway)

T-6A Texan II

The T-6A Texan II is a single-engine, two-seat primary trainer designed to train Joint Primary Pilot Training, or JPPT, students in basic flying skills common to U.S. Air Force and Navy pilots. (Photo: USAF)

T-6A Texan II

Two T-6A Texan IIs fly in formation over the base here May 19. The T-6A Texan II is replacing the T-37 Tweet as the primary trainer for Air Force pilots. (U.S. Air Force photo by Tech. Sgt. Jeffrey Allen)

T-6A Texan II

The T-6A Texan II performs a "gear down" pass. The Texan is a single-engine, two-seat primary trainer designed to train Joint Primary Pilot Training, or JPPT, students in basic flying skills common to U.S. Air Force and Navy pilots. The trainer is phasing out the aging T-37 fleet throughout Air Education and Training Command. (U.S. Air Force photo by O.J. Sanchez)

T-6A Texan II

A T-6A Texan II taxis into position here. The 12th Flying Training Wing was the first Air Force installation to fly the Texan and is the host unit for the T-6A Texan II Demonstration Team. (U.S. Air Force photo by Master Sgt. Dave Nolan)

T-6A Texan II

A T-6A Texan II banks over the south Texas landscape during a 12th Flying Training Wing Pilot Instructor Training flight. The 12th FTW was the first Air Force installation to fly the T-6A and is the host unit for the T-6A Texan II Demonstration Team. (U.S. Air Force photo by Master Sgt. David Richards)

T-6A Texan II

The T-6A Texan II is a single-engine, two-seat primary trainer designed to train Joint Primary Pilot Training, or JPPT, students in basic flying skills common to U.S. Air Force and Navy pilots. The trainer is phasing out the aging T-37 fleet throughout Air Education and Training Command. (U.S. Air Force photo by Master Sgt. David Richards)