that describe methods of delivering personnel, equipment, and supplies from a transport aircraft
at a high altitude
via free-fall parachute
insertion. HALO (High Altitude-Low Opening) and HAHO (High Altitude-High Opening) are also known as Military Free Falls
In the HALO technique, the parachutist opens his parachute at a low altitude after free-falling for a period of time, while in the HAHO technique, the parachutist opens his parachute at a high altitude just a few seconds after jumping from the aircraft. HALO techniques date back to 1960 when the U.S. Air Force was conducting experiments that followed earlier work by Colonel John Stapp in the late 1940s through early 1950s on survivability factors for high-flying pilots needing to eject at high altitudes. In recent years, the HALO technique has been practiced by civilians as a form of skydiving. HAHO is used for delivering equipment, supplies, or personnel, while HALO is generally used only for personnel.
In a typical HALO/HAHO insertions, the troops are dispatched from altitudes between and .
The origins of the HALO technique date back to 1960 when the U.S. Air Force
was conducting experiments that followed earlier work by Colonel John Stapp
in the late 1940s
through early 1950s on survivability factors for high-flying pilots needing to eject at high altitudes. Stapp, a research physicist and medical doctor, used himself as a human guinea pig in rocket sled tests to determine whether or not wind impact would kill ejecting pilots. Stapp also solved many of the issues involved in high altitude flight in his earliest work for the Air Force, and subjected himself to exposure to altitudes of . Subsequently, he helped develop pressure suits and ejection seats, which have been used in jets ever since. As part of the experiments, on August 16
, Colonel Joe Kittinger
performed the first high altitude jump at an altitude of above the Earth
's surface. However, the technique was used for combat for the first time in the U.S. military involvement in Laos, when members of MACV-SOG
performed the first high altitude combat jumps. SEAL Team SIX
of the United States Navy
expanded the HALO technique to include delivery of boats and other large items in conjunction with parachutists.
The technique is used to airdrop supplies, equipment, or personnel at high altitudes when aircraft can fly above Surface-to-Air Missile (SAM) engagement levels through enemy skies without posing a threat to the transport or load.
For military cargo airdrops, the rigged load is pulled from the aircraft by a stabilizing parachute. The load then proceeds to free-fall to a low altitude where a cargo parachute opens to allow a low-velocity landing. Military personnel will later move to the landing point in order to secure the equipment or to unpack the supplies.
In a typical HALO exercise, the parachutist will jump from the aircraft, free-fall for a period of time at terminal velocity, and open his parachute at a low altitude. The combination of high speed downwards, and minimal metal and forward air-speed serves to defeat radar, enabling a stealthy insertion.
The HAHO technique is used to airdrop personnel at high altitudes when aircraft are unable fly above enemy skies without posing a threat to the jumpers. In addition, HAHO parachute jumps are employed in the covert insertion of military (generally special forces) personnel into enemy territory, in circumstances where the covert nature of an operation may be compromised by the loud noise of parachutes opening at low altitude.
In a typical HAHO exercise, the jumper will jump from the aircraft and deploy the parachute at a high altitude, 10–15 seconds after the jump (typically at or so). The jumper will use a compass or GPS device for guidance while flying for 30 or more miles. The jumper must use way points and terrain features to navigate to his desired landing zone, and correct his or her course to account for changes in wind speed and direction. If deploying as a team, the team will form up in a stack while airborne with their parachutes. Usually, the jumper in the lowest position will set the travel course and act as a guide for the other team members.
This type of parachuting technique can be dangerous. At high altitudes of the Earth's atmosphere
(greater than 22,000 feet (7 600 m), the oxygen
required for human respiration
is scarce. Lack of oxygen can lead to hypoxia
A typical HALO exercise will require a pre-breathing period (30-45 minutes) prior to jump where the jumper breathes 100% oxygen in order to flush nitrogen from their blood stream. Also, a HALO jumper will employ an oxygen bottle during the jump. Danger comes from medical circumstances affecting the jumper. For example, cigarette smoking, alcohol and drug use (including antihistamines, tranquilizers, sedatives, and analgesics), anaemia, carbon monoxide, fatigue and anxiety can all lead to a jumper being more susceptible to hypoxia. In addition, problems with the oxygen bottle and during the changeover from the pre-breather to the oxygen bottle can result in the return of nitrogen to the parachuter's bloodstream and, therefore, an increased likelihood of being affected by hypoxia. Just one breath of regular air will bring the jumper's blood nitrogen levels close to normal. A jumper suffering from hypoxia may lose consciousness and therefore be unable to open his parachute.
Another risk is from the low ambient temperatures prevalent at higher altitudes. The jumper may face subzero temperatures and can experience frostbite. However, HALO jumpers generally wear polypropylene knit undergarments and other warm clothing to prevent this.
As with all skydiving, participants run the risk of serious injury or death due to canopy malfunction, as well as the rapid deceleration inherent to landing with, or without, a functioning parachute.
In a typical HALO exercise, a parachuter will jump with:
- an altimeter
- an automatic [parachute] activation device (AAD).
- a parachute
- a knife
- a helmet
- a pair of gloves
- a pair of military free-fall boots
- oxygen available on board the aircraft
- bailout oxygen
- a 50-100+ pound combat pack with fighting and sustenance gear
List of HALO/HAHO capable units
References in fiction
- In the novel Hell Island, Shane M. Schofield's Marine Recon team, a Delta Force team, a squad of SEALs and a force from the 82nd Airborne Division perform a HALO jump onto an aircraft carrier docked on 'Hell Island'.
- In the novel The Fist of God, Mike Martin and other soldiers perform a HALO jump over Iraq in order to find and mark the location of the weapon known as the Fist of God.
- In the novel Crisis Four, Nick Stone and other SAS troopers perform a HAHO jump over Syria in order to find and kidnap a person with ties to Bin Laden.
- In the novel Time to Hunt, by Stephen Hunter, 50+ year old hero Bob Lee Swagger performs a night HALO jump in the dark onto snow.
Film and television
- In Air Force One (1997), the opening scene features a special operations unit performing a HAHO jump.
- In The Wild Geese (1978), 50 mercenaries performs a HALO jump from a C-130 Hercules.
- In the last episode of the fourth season of Alias, Sidney Bristow and her comrades-in-arms HALO-jump.
- In the first season of JAG (1995), Harm performs a HALO jump along with SEAL TEAM 2.
- James Bond performs HALO jumps in the films The Living Daylights (with 002 and 004), Tomorrow Never Dies, and Die Another Day.
- In Navy SEALs (1990), Michael Biehn and his Navy SEAL Team HALO jump and then swim into a coastal town.
- In the film Reign of Fire (2002), the Archangels are HALO jumpers who risk their lives as bait for the dragons.
- In Tears of the Sun (2003), Bruce Willis and his team of Navy SEALs HALO near the Mazon Rainforest. The film showcases about 30 seconds of the HALO process. During filming of the HALO jump, one of the stuntmen drowned after landing offshore and failing to escape his parachute.
- The episodes "First Responders" and "Freefall" of the television show The Unit The members of the Unit HAHO jumps in "First responders" and HALO in "freefall".
- In an episode of The West Wing, a Navy SEAL dies of hypoxia after completing a HALO jump.
- In the French film Taxi 2, a taxi is dropped in a HAHO operation over Paris.
- In the direct-to-video film Behind Enemy Lines II: Axis of Evil, three Navy SEALs are mistakenly HALOed into North Korea.
- In the video game Crysis the protagonist, Jake Dunn, and his team perform a HALO jump onto an island that a meteor has crashed into.
- In the video game Metal Gear Solid 3: Snake Eater, set in 1964, the protagonist Naked Snake performs the world's first HALO jump. Solid Snake uses the same technique in Metal Gear: Ghost Babel.
- Sam Fisher performs HALO jumps in Splinter Cell, Splinter Cell: Chaos Theory, and an interactive real-time HALO jump in Splinter Cell: Double Agent.
- Tom Clancy's Ghost Recon Advanced Warfighter for the PC also features an interactive HALO jump in the first mission.
- In the PlayStation 2 video game Spy Fiction, the first level begins with a HALO jump.
- The opening pre-rendered scene for the Alaskan pipeline mission in SOCOM: U.S. Navy SEALs features a SEAL squad performing a HALO insertion in gear suitable for Arctic conditions.
- The second mission in James Bond 007: Nightfire begins with a video of the titular character HALO jumping out of a C-141 Starlifter onto the top of a castle.
- In the video game Battlefield 2142 the player may earn a "HALO Ribbon" award for a parachute jump that lasts longer than 10 seconds. However the conditions needed to achieve this ribbon more closely resemble a HAHO jump.
- In the Eidos PC game Just Cause, the player can perform real time controllable HALO jumps.
- In the game Call of Duty 4: Modern Warfare, before the mission Ultimatum begins, the player and his team perform a HALO jump into Russian territory that causes Ssgt. Griggs to get separated from the squad.
- In the game Shadow Ops: Red Mercury the level "Man Overboard" starts with a HALO drop
- In the Playstation 3 game Ratchet & Clank Future: Tools of Destruction, Ratchet, along with robots Cronk and Zephyr perform multiple HALO jumps while avoiding missiles or other obstacles during the free fall.
- In the game Grand Theft Auto: San Andreas CJ and several triad gang members perform a HALO jump while infiltrating an enemy gang headquarters.
- In the comic book The Punisher, Castle performed a HALO jump into Siberia during the "Mother Russia" story arc of the Marvel MAX series.
- The HALO jumper for the G.I. Joe team is named Ripcord.
- Divine, Mark (2004). Navy SEALs Air Operations - Free Fall: HALO/HAHO (HALO HAHO/Permissions). US Navy SEAL 1989 to present. Founder of NavySEALs.com
- Gempis, Val (July 1997). A Bad Altitude Airman. US Air Force. United States of America.
- Black, Mike. HALO jump over Yuma Proving Ground, AZ US Marine Corps. United States of America.
- US DOD (June 5, 2003). US DOD Dictionary of Military Terms US Department of Defense. United States of America.
- US DOD (June 5, 2003). US DOD Dictionary of Military Terms: Joint Acronyms and Abbreviations US Department of Defense. United States of America.
- McKenna, Pat (July 1997). A Bad Altitude Airman. US Air Force. United States of America.
- US Army Infantry School (November 1, 1995). Lesson 3: Airlift Requests and Personnel Used in Airborne Fundamentals of Airborne Operations, Edition B. US Army Infantry School. US Army. United States of America.
- McManners, Hugh (2003), Ultimate Special Forces, pub Dorling Kindersley http://doi.contentdirections.com/mr/dk.jsp?doi=10.1221/0789499738