‘When I Have Your Wounded’: The Air Ambulance’s Enduring Role in the Survivability Story

Of all the missions U.S. combat aircraft fly—and the survivability community supports—arguably none is more important than the swift and sure transport of our wounded warriors from the battlefield to life-saving treatment facilities. From the earliest days of employing aircraft—particularly rotorcraft—in combat operations, military leaders have recognized the utility of these vehicles in helping to address the critical medical evacuation (medevac)/casualty evacuation (casevac) requirement. In fact, the very first use of a helicopter in combat was reportedly to rescue four injured Allied soldiers in Burma during World War II [1]. And in the 80+ years since that rescue, “air ambulances” have continued to play an important role not only in the history of U.S. combat aviation but also in the ongoing efforts to make these aircraft the most survivable and effective they can be.

Send the Eggbeater In

One might imagine the first medevac mission as possibly resembling one of the carefully planned and precisely executed air rescue missions we know today, but that wasn’t the case. When U.S. Army pilot Lt. Carter Harman got the order in the spring of 1944 to “send the eggbeater in” and fly his Sikorsky YR-4B Hoverfly more than 500 miles and over a 5,000-ft-high mountain range to rescue an Army pilot and three injured British soldiers stranded behind enemy lines in a Burmese jungle, the probability of success didn’t look high [2].

To be honest, Harman (pictured in Figure 1) was the only qualified helicopter pilot available to fly the mission; and his newly assembled, underpowered Hoverfly had a recommended range of only 100 miles at 65 MPH and an altitude rating of only 4,000 ft. Furthermore, the aircraft’s wooden ribs and fabric skin made it highly vulnerable to enemy fire. Nonetheless, with extra cans of fuel filling his copilot seat, Harman set off on the unprecedented one-man mission, reportedly having to stop every 100 miles to refuel and navigate [2].

After he eventually reached the injured soldiers—who’d never even seen a helicopter before, much less ridden in one—it took Harman four separate trips and another two days to evacuate each of them to safety. The 200-HP Hoverfly was pushed to its limits in the Burmese heat and humidity, with Harman even having to use a jerking motion to get the heavily vibrating helicopter off the ground at times. At the end of the second trip, the aircraft’s lone radial engine finally overheated and seized, sending the helicopter down in smoke. So, Harman waited on a riverbank overnight to allow the engine to cool, just hoping it would restart before Japanese patrols could find the remaining soldiers. Fortunately, the aircraft fired back up the next day, and Harman was able to finish the mission (though the engine would seize again on the last trip) [2].

Much would change, of course, in rotorcraft technologies and tactics in the many years and conflicts that have passed since that first medevac mission, but Harman’s historic flight would highlight several basic design and engineering vulnerabilities, requirements, and priorities that the survivability community still focuses on today—namely, the never-ending need for more range, speed, power, payload capacity, and threat protection.

Angels of Mercy

While World War II provided the proof of concept for the use of air ambulances in combat, Korea would be the conflict in which aeromedical evacuation missions would truly take flight. In 1951, the Army officially assigned four helicopter detachments to the 8^th U.S. Army surgeon. Dubbed the “Angels of Mercy” by soldiers on the ground, these single-engine Bell H-13 Sioux helicopters—as well as some Hiller H-23 Ravens and, later, H-19 Chickasaws—transported approximately 18,000 casualties to forward-deployed Mobile Army Surgical Hospitals (aka M*A*S*H units) during the war [3, 4]. (The iconic bubble-shaped canopy, exposed frame, and external litters of the H-13 [pictured in Figures 2 and 3] would later become familiar sights to viewers of the popular 1970s television series “M*A*S*H,” which featured the helicopter flying in wounded during the opening credits of every episode.)

In 1952, the first dedicated medical aviation unit, the Army’s 49^th Medical Detachment (Air Ambulance), was established. These helicopters, however, were still highly vulnerable to ground fire, environmental conditions, and other hazards, so medevac missions were still restricted (at least officially) to only the most serious of injuries and only daytime flights. Nonetheless, air ambulances still made a difference, dropping the death rate of evacuated patients before they reached medical facilities from a reported 4.5% in World War II to 2.5% in Korea [3, 4].

Father of the Dustoff

By Vietnam, military leaders had begun to realize that even the world’s best trauma care capabilities, facilities, and providers didn’t matter if the wounded couldn’t get to them—and get to them quickly! Thus, a literal army of Bell UH-1 (or “Huey”) helicopters, the undisputed workhorse of Vietnam, would be used to medevac more than 900,000 casualties by war’s end (see Figure 4) [2, 4].

One of the early and most influential medevac leaders during this time was Army Maj. Charles Kelly, the fearless commander of the 57^th Medical Detachment (Helicopter Ambulance). In 1962, Maj. Kelly (pictured in Figure 5) began using the term “Dust Off” (now usually spelled “Dustoff”) as his radio call-sign. The term—which would eventually be applied to the whole detachment and then to all U.S. medevac crews everywhere—was derived from the windstorm created by the spinning rotor blades as the aircraft arrived on scene [4, 5]. And what a welcomed windstorm it was to those injured and awaiting help!

Kelly was determined to let nothing prevent him or his team—which originally was composed of only five aging UH-1B’s and nine overworked pilots—from accomplishing their mission. Whether it was flying medevac rescues himself, pioneering new evacuation techniques (e.g., for night and other particularly hazardous operations), training other medevac pilots, or lobbying military leaders on the importance of dedicated medevac units (and thus the critical need for more many more pilots and aircraft), Kelly’s core philosophy was simple: “No comprise. No rationalization. No hesitation. Fly the mission. Now! [5]”

As a pilot, Kelly didn’t care about the time of day or night, the weather conditions, or the intensity of the battle around him. He also didn’t care if the injured were American, Allied, South Vietnamese, or Viet Cong personnel. He transported all with the same intensity, often taking the most demanding schedules and most dangerous missions himself. In fact, of the 1,600 casualties the team’s five helicopters ultimately evacuated from the Mekong Delta, Kelly personally evacuated more than 500 of them [6].

During one of those missions, the fuel line on Kelly’s helicopter was punctured. With JP-4 jet fuel spraying everywhere, he flew on undeterred, completed the evacuation, and landed the aircraft just as the engine sputtered to a stop with a bone-dry fuel tank. Then, on the first day of July 1964, Kelly flew into a hot landing zone (LZ) near Vinh Long to retrieve some wounded American and South Vietnamese soldiers. U.S. ground observers radioed that the area was too dangerous and urged him to abandon the rescue immediately, but Kelly calmly responded with the phrase that would thereafter be used to portray the brave and selfless spirit of U.S. Dustoff crews everywhere: “When I have your wounded” [5, 6].

Shortly after Kelly uttered these words, his low-hovering Huey was peppered on multiple sides by enemy gunfire, with one round piercing his heart and instantly claiming his life. For his selfless bravery, Maj. Kelly—the Father of the Dustoff, and the 149^th American to die in action during the war—was posthumously awarded the U.S. Distinguished Service Cross, as well as the South Vietnamese Cross of Gallantry and the National Order of Vietnam [5, 6].

Race Against the Golden Hour

Even before Vietnam ended, military leaders, analysts, and others—including those in the newly emerging aircraft survivability engineering discipline—began poring over the large amount of combat data collected during the 20-year conflict. Not only did these practitioners want to understand how to better plan and execute aeromedical evacuations (and countless other kinds of missions), but they also wanted to understand how to improve the survivability and effectiveness of the aircraft flying, and being developed to fly, them.

One significant result of these efforts was the emergence of the Sikorsky UH-60 Black Hawk (shown in Figure 6) beginning in the late 1970s. Replacing the Huey as the primary U.S. air ambulance, the Black Hawk was designed specifically to address many of the previously identified rotorcraft vulnerabilities, requirements, and priorities. The helicopter had more speed, range, power, and versatility than its predecessors and featured many survivability enhancements, including self-sealing fuel tanks, ballistic-tolerant rotor blades and systems, run-dry gearboxes, an armor-protected cockpit and critical components, redundant hydraulic and electrical systems, crash-resistant seats and landing gear, and dual engines with improved hot and high-altitude capabilities [7].

Speed and range would continue to be particularly important factors in the ongoing success of U.S. medevac aircraft and missions. Studies revealed that almost 90% of combat deaths occur before casualties reach a medical treatment facility, and 80% of these deaths occur within the first hour of injury—the so-called golden hour [8]. So, survivability and other aviation practitioners would invest significant time and effort over subsequent decades to identify and implement a wide variety of both technological and tactical improvements to help the Black Hawk and other U.S. medevac aircraft reach the wounded and get them loaded, stabilized, and delivered to hospitals as quickly as possible. In short, it was a never-ending race against the golden hour.

Dustoffs in the Desert

The next major tests for air ambulance performance and improvements were the U.S. conflicts in Iraq and Afghanistan. Not only was the lethality of the weapons used—and the severity of the wounds they often inflicted—much greater than those of previous conflicts, but the harsh desert environments and remote locations of many of the battles further challenged medevac operations. Afghanistan proved to be especially challenging, with its 18,000-ft mountain ranges, fewer hospitals, and routinely longer flight distances to reach them. Thus, golden-hour delivery times of casualties were often unattainable [2, 4].

Nonetheless, the survival rate of U.S. casualties in these conflicts still rose from approximately 75% in Vietnam to a remarkable 92%, the highest survival rate in the history of warfare [4]. Numerous factors combined to produce this dramatic result, including advancements in combat medicine and surgical techniques themselves; more and better medical training of both flight crews and front-line personnel; and the possession of clear U.S. air superiority and large amounts of uncontested territory and airspace in which to operate [4, 9].

To mitigate the golden-hour problem, leaders also recognized that advanced life-saving treatment had to begin long before casualties arrived at hospitals. So, flight medics were trained and certified to provide longer and more advanced (paramedic-level) care for longer medevac flights. In addition, improved in-transit communication—including videoteleconferencing—between flight crews and hospitals enabled coordinated life-saving treatment plans to begin as soon as a casualty arrived on board (if not before) [9].

Of course, the Black Hawk (and its variants) and other medevac aircraft continued to advance as well, and the remarkable casualty survival rate seen in Iraq and Afghanistan was certainly also a testament to the many years of research, development, and enhancement that the survivability community and others had put into U.S. air ambulance platforms.

Over the Horizon

Today, the U.S. military boasts the world’s largest and most capable fleet of tactical and strategic aeromedical evacuation aircraft in existence. Joining the numerous Black Hawk models—including those equipped with customized medevac packages—helicopters such as the CH-47 Chinook and V-22 Osprey, as well as numerous fixed-wing platforms, are used in concert to transport casualties off the battlefield to trauma and long-term care facilities both in and out of theater [10].

However, military leaders also recognize that more and better capabilities will likely be needed for future conflicts. For example, in the much-studied scenarios of potential peer and near-peer hostilities in the Indo-Pacific theater (where U.S. air superiority and/or uncontested operational environments may not be guaranteed), a large number of casualties could be produced in remote, hard-to-access areas [10]. Thus, the need for more medevac aircraft—and increased speed, range, and survivability in them—is expected to remain as strong as ever.

The most advanced U.S. air ambulance fielded to date is the Black Hawk HH-60M, which features numerous technological improvements that have significantly enhanced the Black Hawk’s medevac capabilities and performance, including [11]:

• Two full authority digital engine control (FADEC)-equipped T700-GE-701E engines, with increased horsepower, cruising speed, rate of climb, lift capacity, and range
• Increased (275 nautical mile) range, which can be further increased with a 400-gal external fuel system
• A max hovering out of ground effect (HOGE) gross weight of 21,000 lbs.
• A fully digitized cockpit for better situational awareness
• Dual digital flight control computer, moving map, storm scope, and radio systems
• A new GPS/inertial navigation system
• An improved-durability gearbox
• Newly designed composite rotor blades
• An upgraded forward-looking infrared (FLIR) and external hoist
• An upgraded medevac mission equipment package (MEP) kit
• An Integrated Vehicle Health Management System (IVHMS)
• Onboard oxygen-generation capability
• An environmental control system to help stabilize patients suffering from heat or cold injuries
• A reconfigurable interior with litters for six patients in addition to crew and flight medics.

Much work also continues on the highly anticipated Future Long-Range Assault Aircraft (FLRAA) (shown in Figure 7), which is part of the Army’s Future Vertical Lift (FVL) helicopter replacement program. Expected to possess roughly twice the speed and range of current medevac aircraft, as well as greatly increased survivability and endurance, the FLRAA is planned to complement—and eventually replace—the Black Hawk as the primary U.S. air ambulance [12].

Finally, many aviation leaders continue to look to the rapid development and proliferation of autonomous unmanned aerial vehicles (UAVs) (aka, drones) as perhaps the most promising technological advancement for future aeromedical evacuation operations. Though much work remains to be done in this area, the potential benefits of U.S. unmanned medevac capabilities are clearly far-reaching in terms of helping to alleviate manpower and resource challenges, maximize force effectiveness, and—most importantly—save the lives of U.S. combat personnel all over the world [13].

References

1. History website. “First Combat Helicopter.” https://www.history.com/topics/inventions/first-combat-helicopter-video, accessed 19 February 2025.
2. National Museum of the United States Army website. “MEDEVAC.” https://www.thenmusa.org/armyinnovations/innovationsmedevac/, accessed 20 November 2024.
3. Hughes, Kaylene. “Army Helicopters in Korea, 1950 to ’53,” U.S. Army website, https://www.army.mil/article/177302/army_helicopters_in_korea_1950_to_53.
4. Benitz, Jennifer. “Always Ready for the Next Mission: Pilots Highlight Evolution of Army’s Sacred Medevac Duty.” Association of the United States Army website, https://www.ausa.org/articles/always-ready-next-mission-pilots-highlight-evolution-army%E2%80%99s-sacred-medevac-duty, published 24 October 2019, accessed November 2024.
5. Zabecki, David. “The Father of Dustoff.” HistoryNet website, https://www.historynet.com/the-father-of-dustoff/, published 4 April 2018, accessed November 2024.
6. TIME website. “South Viet Nam: One Mission Too Many.” https://time.com/archive/6808887/south-viet-nam-one-mission-too-many/, published 10 July 1964, accessed November 2024.
7. Leoni, Ray. Black Hawk: The Story of a World Class Helicopter. American Institute of Aeronautics and Astronautics, 1 August 2007.
8. Alexander, Maj. Gen. George A. (U.S. Army Retired). “The History—and Future—Of Combat Care.” Association of the United States Army website, https://www.ausa.org/articles/history%E2%80%94and-future%E2%80%94-combat-care, published 26 June 2018, accessed November 2024.
9. Vergun, David. “Survival Rates Improving for Soldiers Wounded in Combat, Says Army Surgeon General.” U.S. Army website, https://www.army.mil/article/173808/survival_rates_improving_for_soldiers_wounded_in_combat_says_army_surgeon_general, published 24 August 2016, accessed November 2024.
10. Attariwala, Joetey. “The Future of Military Medevac.” AirMed&Rescue, issue 141, https://www.airmedandrescue.com/latest/long-read/future-military-medevac, published September 2023, accessed December 2024.
11. Wriston, Edwin. “W. Va. Guard Unit Receives First New MEDEVAC HH-60M ‘Mike’ Black Hawk Helicopter.” West Virginia National Guard website, https://www.wv.ng.mil/News/Article/2998333/wva-guard-unit-receives-first-new-medevac-hh-60m-mike-black-hawk-helicopter/, published 13 April 2022, accessed December 2024.
12. PEO Aviation. “FLRAA Achieves Milestone B, Enters Next Phase of Development.” https://www.army.mil/article/278591/flraa_achieves_milestone_b_enters_next_phase_of_development, published August 2024, accessed December 2024.
13. Nichols, Gregory. “Autonomous Platforms for Casualty Evacuation.” HDIAC-BCO-2024-532, State-of-the-Art Report, Homeland Defense & Security Information Analysis Center, April 2024.