Balloons’ two-hundred-year-long role in warfare and espionage continues today, with developments matching the technology of the times. In the modern era, they supplement more sophisticated means of gathering intelligence and conducting air-based tasks during war. However, in previous centuries, a balloon with an observer above the war zone was enough to change the course of battles. Over time, balloons’ operational use has evolved from mere reconnaissance to complex means of defence against air strikes. In ongoing conflicts, including Ukraine and Gaza, their use includes disruption of air forces and aiding in radio signal relay. Their established status as relatively inexpensive, versatile, and productive tools almost guarantees their continued use in warfare in the coming years.
Images Sourced From: Chase Doak, AMN Benjamin Andera, US Marine Corps, A Year Of War
1 History
1.1 Origins of balloons in warfare
Eleven years after the invention of the first man-carrying balloon, the artifact was given a military purpose. Its first military use in 1794, during the French Revolutionary War, during the Battle of Fleurus, was as a reconnaissance tool. The balloons were filled with hydrogen. The invention provided military forces with an aerial vantage point and helped oversee behind enemy lines with less risk for the soldiers. [source] [source]
During the Austrian besiege of Venice in 1849, the balloons were first utilised for bombing purposes. Austrian forces loaded time-fused bombs in hot air balloons and released them towards Venice. However, wind changes prevented most balloons from reaching their target, with some even blowing back to Austrian forces. After these early trials, colonial powers utilised balloons in bombardments during battles, such as the French capture of Dien Bien Phu in Vietnam. [source]
1.2 U.S. Civil War (1861-1865)
During the United States’ Civil War, both sides utilised balloons for reconnaissance and artillery spotting. While both the Union and the Confederacy utilised balloons, the Union’s balloon program proved to be more successful and better organised, which led to the creation of the Balloon Corps under the leadership of Thaddeus Lowe. Designs of the balloons intended for them to be constantly tethered to the ground and ascend up to 1,000 ft or roughly 304 meters. Observers inside the balloons communicated with the soldiers on the ground using telegrams or signal flags. The larger balloons carried full telegraphy gear in the basket. The military disbanded the Balloon Corps in 1863.
1.3 Franco-Prussian War and the Siege of Paris
In September 1870, during the Franco-Prussian War, the French utilised balloons during the Siege of Paris. Surrounded by Prussians, the French used balloons to communicate with Tours, the provisional government at that time. Given the directions of the wind, the balloons were not able to fly back into Paris. This meant that the French needed to continuously build new balloons. Out of a total of 66 balloons that had left Paris, 58 landed safely. The balloons carried with them a total of over two million pieces of mail and roughly 102 people. [source]
1.4 British Forces in Africa and the Boer War Balloons
The British army began utilising balloons during their battles in Africa. In 1884, the British sent balloons to South Africa to assist a force operating in what is now Botswana. One year later, in 1885, they deployed balloons in Suakin, Sudan. While their use helped in spotting enemy forces, observers regard their deployment as only moderately successful. [source] [source] [source]
Over a decade later, in 1899, South Africa saw four Royal Engineers Balloon Sections during the Second Boer War. They served as artillery observers from the British forces. The balloons proved to be successful in providing vital information on enemy positions and the direction of artillery. The balloons utilised by the British were commonly small and were only able to lift up to one person.
1.5 Balloons in World War 1
Military forces heavily utilised barrage balloons for warfare during the First World War. Their average size was around 19.5 meters long, 9.5 meters high, and 7.62 meters in diameter. Forces deployed these balloons mainly to protect cities, shipping harbours, and coasts. Military forces used this balloon type mainly for defensive purposes. During World War I, U.S. balloon companies maintained a significant presence in France. The French delivered training and much of the equipment. During this time, soldiers were operating exclusively in the Caquot, considered the best balloon at the time. Flying in balloons at that time allowed soldiers to observe up to 40 miles (64.3 km) behind enemy lines. [source] [source] [source] [source]
1.6 War Balloons in World War 2
The use of balloons during World War II was extensive. The British utilised barrage balloons -a large balloon with three fins at the back, with the top half filled with hydrogen and usually tethered to a vehicle- as obstructions to aircraft flight paths to protect urban centers and relevant locations. Later, barrage balloons proved to be helpful means of defence against the Luftwaffe. If airplanes flew into their metal cables, the cables would damage or destroy them. Additionally, if pilots tried to shoot the balloon, the hydrogen would explode and catch nearby aircraft on fire. [source] [source]
A considerable operation during this period was ‘Operation Outward’ in which the British Army decided to release balloons towards Germany in an attempt to disrupt their communication lines and generally cause destruction. However, the British were not the only ones utilising balloons during WW2. The Japanese, for example, utilised balloons as weapons delivery system. They sent incendiary bombs towards the United States, killing a total of six people in Oregon on 5 May 1945. [source] [source] [source] [source]
1.6.1 Women’s Auxiliary Air Force and Women’s Royal Naval Service in War Balloon Operations
In 1940, the Balloon Command took the decision of training the members of the WAAF (Women’s Auxiliary Air Force) to replace men as balloon operators, with the purpose of freeing the men for active service. In 1941 WAAF became a part of the Armed Forces of the Crown. The initial experiments demonstrated women’s capabilities to handle barrage balloons and one year later, in 1942, women had replaced over 10,000 men in the balloon operator posts. Women were additionally the ones operating the balloons released towards Germany in ‘Operation Outward.’ The goal of this operation was to disrupt communication lines, aircraft, and rail lines, or to release incendiaries that were highly flammable in occupied Europe. The Women’s Royal Naval Service sourced these balloons from a surplus of weather balloons and released an estimated 100,000 of them. [source] [source]
1.6.2 320th Battalion
During the invasion of continental Europe in the Second World War, one Barrage Balloon Battalion was crucial for the success of D-Day. The 320th Battalion was one of four composed entirely of African American recruits. During D-Day, the 320th Battalion moved the balloons from the ships to the beaches to protect the landing forces from expected aerial attacks by Germany. However, the previous bombardment of the beach failed to take down the expected number of German defensive positions, causing the 320th Battalion to face heavy artillery fire. Several balloons were shot down or cut loose. [source]
Despite the setbacks, battalion 320 was able to establish by the night of 7 June, 20 balloons in Omaha beach and 13 in Utah beach. Although German attacks shot down balloons and the forces replaced them, the balloons proved essential to the success of the D-Day invasion and the end of German control over Europe. [source]
1.7 Cold War and Project Moby Dick
In January 1956, the United States Air Force conducted an operation aimed at gathering information on the Soviet Union. The operation, called Project Moby Dick, launched hundreds of spy balloons equipped to take photographs of their surroundings and later reappear in friendly airspace. The US government widely preferred using balloons for espionage over manned flights, which were less safe on Soviet territory. The operation released balloons in Western Europe and Turkey with the aim of having them fly towards U.S. bases in Japan. However, enemy forces shot down 90% of the hundreds of balloons, and crews recovered only 44. One month after the project started, in February 1956, President Eisenhower stopped it after the Russian Ambassador to the U.S. protested the violation of their airspace. Despite the low percentage of balloons recovered, this project led to the uncovering of a major nuclear installation in Dodonovo, Siberia. [source]
2 Modern Use of Balloons in Warfare
2.1 Iraq and Afghanistan Espionage Balloons
During the United States war on Iraq, military forces utilised balloons for observation and intelligence purposes. The military equipped these balloons with a television camera, infrared night vision, and a laser range finder, enabling complex surveillance and high-quality intelligence gathering. For the operations, military forces utilised similar balloons equipped with cameras, radars, and listening devices. In Afghanistan, US and British forces deployed balloons that reportedly deterred Taliban activities in the areas where they operated, in addition to their initial intelligence purposes. [source] [source] [source] [source]
2.2 Chinese Espionage Balloons and the United States
In 2023, the United States saw the appearance of surveillance balloons belonging to the People’s Republic of China flying roughly 22,000 meters above ground. Additionally, observers have spotted these balloons not only over the mainland US but also over Hawaii and Guam, expanding the range of defense operations. While the United States aims to capture and ground these balloons, conducting the operations is extremely hard, given the altitude and dimensions of the aerostat. Therefore, countermeasures against the balloons are likely to continue evolving. Despite increased media coverage in 2023, observers had already spotted Chinese spy balloons flying over the US in recent years. Additionally, Beijing officials have begun legally contesting what they call ‘near space,’ justifying their flights over sovereign states by flying below outer space and allegedly above sovereign airspace.
In July 2024, the United States Army issued a new requirement for the use of micro-high altitude balloons (microHABS). These balloons operate in the upper edges of the stratosphere, a region that only balloons or ultra-light, solar-powered vehicles can reach. This development is fairly recent and needs further confirmation, but larger high altitude balloons (HABS) are currently operational for surveillance and reconnaissance. However, HABs do not reach the same altitudes as the microHABs. [source] [source]
2.3 Ukraine and Russia War Balloons
In 2023, during the Russian invasion of Ukraine, Russia deployed balloons reportedly aiming to exhaust Ukrainian air defenses. The deployed balloons had corner reflectors, which experts believe the Ukrainian air forces use for confusion or as radar reflectors. [source]
Since 2023, Ukraine has deployed small airships, or balloons, carrying communication antennas, radio repeaters, and drone detectors. Later on, in 2025, Ukrainian forces began utilising balloons to launch kamikaze drones. These balloons were chosen for their fast deployment and the fact that they can stay airborne for several days. Ukrainian startup Aerobavovna started deploying the balloons equipped with radio repeaters, which greatly increased the radio range, and proved to be safer for soldiers who no longer needed to approach frontlines to install them. [source] [source] [source]
This innovative use of tethered balloons proved to be crucial for ground drones, increasing their range. After several prototypes and a year of testing, current aerostat balloons are able to withstand heavy winds, are set up in as few as seven minutes, and can remain airborne for up to seven days. The tethered balloons aim to geolocate Russian drone control transmitters in order to target the operators. [source] [source] [source]
2.4 Israel Espionage Balloons
The Israel’s Air Force (IAF) in January 2024 deployed the Sky Dew; an observation balloon equipped with a radar, aimed at detecting aerial threats from Iran and Syria. Previous balloons by the IAF were utilised in the south of the country, to monitor threats from the east. However, mere months after its launch, in May 2024, Hezbollah targeted the balloon and left it nonoperational. Additionally, Israel is allegedly deploying a secret spy balloon program over the Gaza Strip. However, information on the technicalities are to be confirmed. [source] [source] [source] [source]
5 Core purposes and weaknesses
Balloons in warfare have served similar purposes throughout history. Tethered balloons were vital for observing behind enemy lines and directing artillery fire. Positioning observers and reconnaissance at a higher altitude allows them to see the targets at a greater range than they could on the ground. Additionally, balloons were considered relatively cheap to make and rarely endangered the lives of soldiers. Through time balloons evolved for bombing purposes, with the 1899 Hague Peace Conference eventually banning this practice. Despite their many advantages, balloons are highly susceptible to weather variations, and can be difficult to control. [source] [source] [source]
6 The Future of Balloons in War
With the advancement of more modern means of espionage and control of aerial space, balloons have evolved their core functions to integrate technology. Recent developments such as presumed Chinese spy balloons, disruption balloons and radio transmitter balloons in Ukraine, and developments in the United States’ high-altitude balloons have led to a continuation of balloons use in warfare and espionage. Adaptations to balloons, such as the integration of radio repeaters, communication antennas, and high-end espionage equipment mean that these low-cost war objects are not going to disappear in the near future. [source] [source] [source]
7 Conclusion
While balloons have been around for a long time, their use in warfare is extensive. From France to the US, from South Africa to Iraq, these tools have been deployed largely and intensively. Technological developments in war have helped make these inflatables safer for humans, and more precise in their missions. Although inspired by a centuries-old innovation, modern warfare and spying continue to use these balloons, making their disappearance unlikely anytime soon. Therefore, new uses and new developments are to be expected in the future.