MARINE CORPS BASE CAMP PENDLETON, Calif. -- Jumping out of a perfectly good airplane at 25,000 feet while traveling 120 mph in freezing temperatures with 100 pounds of gear attached to your body in the pitch-black night is not sane or rational. But that's just what some members of 1st Force Reconnaissance Company, I Marine Expeditionary Force are training to do at this airfield 100 miles east of San Diego.
High Altitude High Opening is a "clandestine means of insertion where the aircraft does not have to fly over the intended target area," explained Master Sgt. Mark A. Packard, jumpmaster with 1st Force Recon Company.
It's the preferred way to insert for a stealthy unit like Force Recon, said Packard — a veteran with more than 750 jumps.
This jump style involves an early parachute release — almost right out of the bird, in this case a C-130 Hercules cargo plane. An early opening allows the jumper to navigate. In contrast, low-opening jumps are faster; the jumper doesn't open his chute until he's 4,000-5,000 feet above the ground.
"The advantage it has over High Altitude Low Opening and static-line jumps is that those types of jumps have to fly over the target, thereby letting the enemy know that you're there. This (is) not tactically feasible for 1st Force Reconnaissance Company missions, since we want to remain undetected.
"The only disadvantage of HAHO would be if an experienced radar operator saw that the aircraft we're traveling in slowed from its traveling speed of 200 knots to 120 knots — he might realize that jumpers were being released," Packard said.
Jumpers don't just drop — they steer their way — to the zone.
"Under normal conditions, we can travel 1,000 meters for every 1,000 feet of elevation, giving us a range of about 25 km. However, we have traveled as far 30 km in favorable conditions," said Staff Sgt. Rodney W. Simpson, 1st Force Recon Co.
Jumping out of the aircraft doesn't just take nerves — it takes skill, too. When the Marines exit the aircraft, they must have a good free fall posture, with back arched and facing the aircraft so they can orient themselves. It's especially important at night, when disorientation is more likely.
Jumpers also must be concerned about their body temperatures and oxygen intake. Every 1,000 feet in elevation, the temperature drops 3.5 degrees Fahrenheit. So, on a 60-degree night, a jump at 25,000 feet puts the air temperature at minus 27.5
degrees.
Also, at 25,000 feet, jumpers must carry a tank of oxygen so they don't pass out. Oxygen deprivation sneaks up on a jumper. So he needs to recognize the signs of deprivation, which is among topics covered in the High Altitude Parachute Course. As part of the course curriculum, Marines experience oxygen deprivation in a special chamber.
Weight is another problem — especially when trying to maintain a good jump posture. Jumpers carry more than 100 pounds of gear as they descend.
The MC-5 Ram Air Parachute System is designed to handle 360 pounds. The parachute and oxygen system weigh 70 pounds, leaving 290 pounds to work with.
"If we have somebody weighing 220-230 pounds then — with his flack, Kevlar, load-bearing vest, and weapon — he will max out the system so his gear must be spread-loaded to other Marines," Packard said.
E-mail Cpl. Storm at stormrm@pendleton.usmc.mil.