From the two-seat cockpit of the University of Iowa’s Aero L-29 Delfin trainer jet, a patchwork of snow-covered fields stretch across the landscape. Ahead, the Boyd Tower rises over the University of Iowa Health Care complex, a familiar landmark from an unfamiliar angle.

Oxygen hums through the hose clipped to my mask. A wire snakes from my helmet, carrying chatter from the ground crew and the two other aircraft in formation. The control stick nudges between my knees; the rudder pedals slide by my boots. On the arm rail, the throttle waits.

We bank east. Off the right wing, a second L-29 and a Beechcraft Bonanza slide into echelon formation. At 200 knots—about 230 mph—we skim the sky at 8,000 feet.

I’m here with the Operator Performance Laboratory (OPL) team, testing new technology for a client. Over the next hour, we’ll climb, dive, and shift formations to push the equipment through its paces. This is what OPL does best: early-stage flight testing for partners including Applied Intuition, Lockheed Martin, Collins Aerospace, and government agencies including the DARPA (Defense Advanced Research Projects Agency) or the US Air Force, Army, or Navy.

Few people know this lab exists, despite its fleet of colorfully painted jets and helicopters and robust portfolio of work. Led by Tom “Mach” Schnell, OPL doesn’t just test hardware. The team of around 20 research scientists, students, and scholars discovers new knowledge about how pilots respond under stress, even how they learn to trust artificial intelligence.

Today, I’m in full flight suit, strapped into one of OPLs oldest birds with a parachute attached to my seat. The L-29s were originally built in Czechoslovakia in the 1950s. Rugged, reliable, and adaptable, these jets can be modified to mimic other aircraft, such as an F-16. They are perfect for researchers chasing data.

Every aircraft in OPL’s fleet of more than a dozen has an interesting story. Schnell found the first L-29 on the Aero Trader website. The XCub, a low-altitude airplane, was gifted to OPL by the U.S. Air Force, knowing it would be put to good use. Seemingly defying the bounds of physics, Schnell and team always find room for each new machine in OPL’s three hangars at the Iowa City Airport.