Most notably, this summer included the June 20 shoot-down of a U.S. RQ-4 Global Hawk over the Strait of Hormuz by Iran. But these events are not entirely uncommon.

Unmanned aircraft have been a part of U.S. military operations since World War II and have led to leaps and bounds in mission capabilities. Drones allow the armed forces to undertake missions that would be too risky or impossible with manned aircraft, and uncertainty as to their presence in future military conflict is all but guaranteed. Countries around the world will increasingly operate on the drone axis, developing capabilities to both employ and combat against drones. After the expensive, high-profile destruction of a Global Hawk in Iran, some historical context of the destruction of U.S. drones by hostile forces is in order.

With that recent context, here is a retrospective of U.S. drones shot down by enemy forces.

June 20, 2019: RQ-9 Global Hawk, Strait of Hormuz

After Iranians shot down this $110 million, 737-sized UAV, the United States was 10 minutes away from a conflict with Iran, CNN reported. The “RQ” designation means that this aircraft does not carry weapons.

June 6, 2019: MQ-9 Reaper, Yemen

This 66-foot-wingspan, $30.2 million, “hunter-killer” drone was shot down by Houthi rebels over Yemen just two weeks before the Global Hawk was brought down. Unlike the Global Hawk, the Reaper’s “MQ” designation means that it carries weapons, which can include Hellfire missiles, Paveway II laser-guided bombs and other guided bombs. Reapers are the primary UAVs used in offensive strikes by the U.S. Air Force, according to military.com. The Pentagon claimed another Reaper was shot down by Houthi forces in August 2019.

March 17, 2015: MQ-1 Predator, Syria

This 55-foot-wingspan, $5 million UAV was likely shot down by Syrian forces during Operation Inherent Resolve, although specifics were not confirmed by the Air Force.

April 7, 1999: RQ-5A Hunter UAV, Yugoslavia

This drone was one of four U.S.-controlled Hunters to be shot down during the 78-day duration of NATO action in the Kosovo war. Hunter flew alongside the Predator and Pioneer drones in the conflict. The early drone was under half of the size of the Reaper and less than a quarter of the size of the Global Hawk and cost $300,000 in 1999, or just over $450,000 today.

1991: RQ-2A Pioneer, Kuwait, Iraq

Of the 34 Pioneers deployed to the Persian Gulf War, only 2 were shot down.

“We think it’s the first electronic capture in history.”

-Adam R. Fein, director of corporate communication at AAI, 1991

The RQ-2A Pioneer was the first modern-style drone flown by the United States. The Pioneer was powered by a 26-horsepower modified snowmobile engine in a 15-foot wingspan frame. In 1991, as a part of Operation Desert Storm, a Pioneer became the first robot to receive a military surrender. Iraqi soldiers surrendered to a Pioneer as it was assessing damage from battleship weapons.

September 11, 1944: Remote Controlled B-17, Germany

This downing was the final attempted execution of Operation Aphrodite, one of the United States’ earliest forays into UAV technology. During World War II, the Air Force modified B-17 bombers to carry large amounts of explosives and be controlled remotely as a way to compete with the more advanced German unmanned aircraft, which included guided bombs. Operation Aphrodite was largely unsuccessful, the first six participating planes crashed off-target without enemy interference and the seventh was shot down. The ninth and final attempt was shot down before it reached its target, U-boat pens in the North Sea.

More information on drone crashes can be found at Drone Wars UK or the Washington Post Drone Crash Database.

But that may have been because U.S. Air Force fifth-generation aircraft, F-22s and F-35s, were noticeably absent from the proceedings.

The two-week multinational training exercise is meant to provide realistic combat experience to pilots in a controlled environment, which increases their survivability on actual combat missions, Senior Airman Eric Fisher, with the 354th Fighter Wing Public Affairs Office at Eielson Air Force Base, said in an email.

The exercise is also an opportunity for airmen from partner nations to improve interoperability and exchange tactics, techniques and procedures, he said. About 2,000 airmen from the U.S., Great Britain, Japan, South Korea and Thailand took part in the exercise, which wrapped June 21.

In April, the Defense Department Inspector General’s Office released an audit report skewering the Alaska range and others in U.S. Indo-Pacific Command, saying they were antiquated and unable to prep units for conventional war.

“As a result, the aviation units in the USINDOPACOM area of responsibility could not train as they would fight,” which is a key tenet of the Pentagon’s 2018 National Defense Strategy, according to the report.

IG investigators determined that the Joint Pacific Alaska Range Complex’s electronic warfare systems are so past their prime that the Air Force’s F-22 Raptor and F-35 Lightning II jets don’t even see them as a threat. That’s because the aircraft technology is more advanced than the range electronic warfare systems, according to the report.

The complex replicates Soviet missile systems from the 1980s, and Air Force officials told investigators that the current systems “do not replicate near-peer threats.”

Army AH-64 Apache pilots also voiced concerns about the Alaskan range, saying that the dumpsters used as targets there “were of poor quality.”

But Capt. Kay Nissen, spokeswoman for the 354th FW, which is part of Pacific Air Forces, said the training range and exercise scenarios “sufficiently challenged” participating aircraft and units.

“There continues to be opportunities to improve the capabilities of the training range to ensure participants receive the most realistic combat-like experience to prepare for future operations,” she acknowledged. “This is why the 354th Fighter Wing has prioritized investing in the Joint Pacific Alaska Range Complex, to include standing up a new detachment specifically designated to find those opportunities for improvement, so warfighters are ready for the high-end fight.”

Aircraft used in the exercise included F-16 Fighting Falcons, A-10 Thunderbolt IIs, KC-135 Stratotankers, Mitsubishi F-2s, C-130 Hercules, UH-60 Black Hawks, HH-60 Pave Hawks, and the MQ-9 Reapers, Fisher said. Airmen were able to use live ordnance and dropped 681,505 pounds of munitions, said Senior Airman Isaac Johnson.

The two-week multinational training exercise is meant to provide realistic combat experience to pilots in a controlled environment, which increases their survivability on actual combat missions, Senior Airman Eric Fisher said in an email.

The exercise is also an opportunity for airmen from partner nations to improve interoperability and exchange tactics, techniques and procedures, Fisher continued. Red Flag-Alaska takes place at the Joint Pacific Alaska Range Complex, which includes a 67,000 square mile range.

When asked about previous equipment issues at the complex and other Air Force facilities, Capt. Kay Nissen, spokesperson for the 354th Fighter Wing, said the training range and exercise scenarios “sufficiently challenged” participating aircraft and units.

“There continues to be opportunities to improve the capabilities of the training range to ensure participants receive the most realistic combat-like experience to prepare for future operations,” she continued. “This is why the 354th Fighter Wing has prioritized investing in the Joint Pacific Alaska Range Complex, to include standing up a new detachment specifically designated to find those opportunities for improvement so warfighters are ready for the high-end fight.”

Aircraft used in the exercise included KC-135 Stratotankers, F-16 Fighting Falcons, Mitsubishii F-2s, C-130 Hercules, UH-60 Black Hawks, HH-60 Pave Hawks, A-10 Thunderbolt IIs and the MQ-9 Reaper, Fisher said. Airmen were able to use live ordnance and dropped 681,505 pounds of munitions, said Senior Airman Isaac Johnson.

John Sopko presented the findings from a report, “Divided Responsibility: Lessons From U.S. Security Sector Assistance Efforts in Afghanistan,” during a speech Thursday at a NATO conference.

“The first challenge is that after 17 years, there is no single person, agency, country or military service that has had sole responsibility for overseeing security sector assistance in Afghanistan,” he said. While the U.S.-NATO commander is largely responsible for the effort, the commander has no direct authority over civilians participating in the mission, he noted, leading to uneven development of the Afghan security force and hindering the standardization of security sector assistance programs in the country.

Furthermore, countries consistently deploy fewer troops than they actually pledge, he said. These “chronic shortfalls” create their own challenges in the mission, he added.

Countries also place caveats on the use of their forces, such as geographic limits, the inspector general said. “When countries were viewed as withholding their full effort, it created the perception of placing a disproportionate burden on others,” he explained.

One study cited in the report found that Afghan leaders prefer working with U.S. advising teams because those teams are not restricted to specific areas.

But Sopko also discussed the benefits of NATO’s involvement in Afghanistan.

Personnel from other nations possess expertise that would not have been available in a solely American mission, he explained. Czech, Lithuanian and Hungarian advisers provide training on Soviet-style aircraft, such as the Mi-35 and Mi-17 helicopters, and Italian, Romanian and Turkish advisers leverage their police training experience, Sopko added.

Coordinating a multilateral approach is also made simpler under a NATO umbrella, he said.

The flight test collected data on drag and vibration impacts on the weapon and the B-52 Stratofortress carrying it. The AGM-183A Air Launched Rapid Response Weapon did not contain explosives and was not released from the aircraft, the Air Force said.

The service noted that such tests are required for all of its weapons systems during development.

“We’re using the rapid prototyping authorities provided by Congress to quickly bring hypersonic weapon capabilities to the warfighter,” Will Roper, assistant secretary of the Air Force for acquisition, technology and logistics, said in a statement. “This type of speed in our acquisition system is essential — it allows us to field capabilities rapidly to compete against the threats we face.”

The United States is working to catch up to adversaries Russia and China on hypersonic weapons technology.

The Air Force awarded a contract to develop the hypersonic missile to Lockheed Martin Missiles and Fire Control in August 2018.

The missile is scheduled to reach early operational capability by fiscal 2022.

The exclusion, from a letter to the speaker of the House from President Donald Trump, is a change from the same report sent six months ago. The report is required by the War Powers Resolution.

The Republican president and Democrats in the House are currently at odds over military support in Yemen, where “a small number” of U.S. military personnel are deployed, according to the June 11 letter.

The latest letter also reveals that the number of U.S. military personnel in Lebanon has declined by 50 percent since the last report, to 60.

The letter cites the territorial defeat of the Islamic State group in Iraq and Syria, but says that “operations against the continuing terrorist threats emanating from Iraq and Syria remain ongoing.”

The U.S. is coordinating its activity in Iraq with the Kurdistan Regional Government, an autonomous entity in the country — something not included in the previous letter.

Personnel numbers in Jordan have increased from 2,795 military personnel to 2,910, since the last update — the latest in a number of consecutive increases.