In Frederick, Okla., former soldiers and civilians honor the Greatest Generation by parachuting using the same techniques and nearly the same equipment as the paratroopers of WWII. WSJ's Ben Kesling joins them for a jump.

FREDERICK, Okla.— Jim Yost has walked battlefields across Europe and driven through the French countryside in the vintage three-quarter-ton troop carrier he keeps at a friend's farm in Normandy.

On a recent chilly morning, the 68-year-old funeral director from Champaign, Ill., took his fascination with World War II to new heights, in the belly of a decades-old propeller plane 1,500 feet above southern Oklahoma cotton fields.

Dressed in WWII military fatigues and a beat-up steel helmet, he nervously pictured all that could go wrong as he waited to jump from the plane using a parachute based on an old-fashioned design that can drop a man on the ground with the same force as a fall from a second-floor window. Instructors had warned about a ripped ear from a bad exit, a severed finger from an errant line, or a snapped ankle or worse from a rough landing.

"We talked so much about handling malfunctions, on my first jump I was not confident," said Mr. Yost, whose prime jumping years in the Army ended more than three decades ago.

Weekend war buffs can drive Cold War-era tanks in Kasota, Minn., shoot .50-caliber machine guns in West Point, Ky., and re-enact Revolutionary War battles in Concord, Mass. But few experiences match the rugged authenticity and potential dangers of the World War II Airborne Demonstration Team's semiannual jump school.

The team, which travels to air shows around the world, formed in 1996 and has been holding the boot camp ever since to train new members and those who just want to test their mettle.

Participants—who have ranged in age from 18 to over 70—pony up $1,250 for the nine-day training program based on the same curriculum used by the first U.S. paratroopers in the 1940s. They sleep in the team's dusty barracks at an old Army airfield built in 1942, spend hours jumping into a sand pit from a 3-foot-tall platform and march in formation from one activity to another.

And that is all before parachuting out of the smoke-belching "Boogie Baby," a propeller-driven 1942 Douglas C-47 Skytrain, which, as befitting an antique machine, had a few mechanical problems during the week.

The World War II Airborne Demonstration Team in Frederick, Okla. Ben Kesling/The Wall Street Journal

"Tell me again why I'm paying to do this?" joked retired Army Lt. Col. Bill Jones, a 55-year-old intelligence analyst from Virginia Beach, Va., as he scraped leftovers into the trash one night after being assigned to KP, or kitchen police.

The days started at 0500 hours, which is to say 5 a.m. That is when 82-year-old retired Army Sgt. Maj. Dayton Herrington, the team's senior drill instructor, tromped into the barracks, flipped on the lights and awakened the trainees with a round of oaths.

After breakfast, the squad of about a dozen students marched in formation to a platform in the middle of a sand pit.

For hours, trainees jumped off the metal platform and crumpled to the ground. The eager students, whose age averaged in the mid-50s, fell on their left sides and right, from various angles, often landing like middle-aged sacks of mush until they had learned the proper technique, distributing the landing shock by touching feet, calf, thigh, butt and back to the ground in rapid succession.

"I kinda cranked my neck," said Mr. Jones, who felt lucky to have escaped without hurting a knee or ankle.

"I like the pit," said 18-year-old Kaitlin Harriott, the youngest trainee and daughter of a member of the team, who nimbly rolled away from each landing, to the envy or annoyance of her comrades.

Five days into the training, students prepared to climb aboard "Boogie Baby," for the first of their five jumps. The two-engine green troop transport sports a pinup girl on its nose and black and white "Invasion Stripes" on its fuselage and wings, just like the markings slapped onto Allied aircraft for D-Day in order to avoid friendly fire.

Students joked nervously and fiddled with their equipment, parachutes strapped to their backs as they waited.

But that first attempt was thwarted by high winds, and later on two mechanical problems delayed jumps, once when a hydraulic valve froze and again when a brake ruptured, oozing fluid onto the runway.

When the plane finally belched to life with flames from the exhaust and great clouds of blue smoke for the first jump, nerves had mostly subsided and students just wanted to get that first jump out of the way.

Once aloft, the trainees stood, a bit off balance in the yawing plane, clipped lines from their chutes to a long steel cable, or static line, running down the center of the plane and crowded toward the rear exit.

At the drop zone the jump master screamed over the engines and wind. "Go! Get out of my plane," he yelled, as the half-dazed students shoved and shuffled out the door into the open sky.

Once out of the plane, the big, round parachutes deployed automatically, jerking the students to heel after about four seconds of falling in the wind.

"It's like jumping into a tornado!" said Peter Roberts, a 55-year-old security officer, from Melbourne, Australia. Then the chute opened and it was like "having a giant eagle grab you by the shoulders," he said.

The parachutes are steerable to some extent, but even old hands can have problems with unpredictable gusts as they try to land near a target spot in the middle of a field.

A couple of years ago, Sgt. Maj. Harrington came down in a tree and got hung up in the crook of a limb. After extracting him, the team sawed off the offending branch and mounted it as a trophy in the corner of the classroom in Frederick.

Mr. Yost, the funeral director, had a similar experience in 2004 when he talked some Dutch WWII re-enactors into letting him jump with them—his first jump in decades. Fickle winds blew him off the drop zone and he landed on the windshield of a car.

He said the training in Oklahoma was just what he wanted, and he fared well considering the decades since his time in the Army. The jump went well for everybody. All five jumps were into nearly breezeless skies, and nobody missed the drop zone.

Sgt. Maj. Harrington, meanwhile, who completed his 131st jump with the team, plans to jump again with the next batch of students next summer, after his 83rd birthday. Ms. Harriott, a high-school senior from Lake Arrowhead, Calif., successfully completed her first five jumps and is ready to return to do it again despite some reservations. "It's terrifying," she said of those first few seconds out of the plane. "It's the falling part. I don't like that."

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