For one afternoon, Carolyn Holland and her family were among the “casualties” of an air disaster in Unity as part of a scripted exercise to ensure local first responders are ready for the real thing.

Holland, of Ligonier, her husband, Monte, and their granddaughter, Jordan, were participants in that 2014 air disaster drill at Arnold Palmer Regional Airport.

These large-scale simulations are conducted every three years to ensure first responders are prepared for emergencies.

After a bus shuttled them to a grassy field, the volunteers were assigned roles. Carolyn was designated as a passenger with fatal injuries, while her husband was assigned a role as a critically wounded traveler who “died” shortly after paramedics reached him.

The Hollands were joined by more than 150 other volunteers, each given a fictional scenario so emergency personnel could determine how best to address a real-life crisis. The assignments are somber, but volunteers help airport officials refine worst-case plans.

Arnold Palmer Regional Airport will host its next drill Wednesday.

“Every three years, we’re required to do a disaster drill to test our airport emergency plan,” said Dylan Kovatch, the airport’s assistant manager. “It’s part of the Federal Aviation Administration’s Part 139 inspections. It helps us keep up with our certification.”

For volunteers like the Hollands, the experience involves a mix of dramatic simulation and significant waiting.

“I hoped they’d take me out on a backboard pulled by an ATV,” Carolyn Holland said. “My granddaughter didn’t care to do that. I told her it would be a good experience, but she reminded me of the time the ambulance took her to a hospital on a gurney.

As paramedics moved through the field, they assessed each volunteer’s written description and responded accordingly. When Carolyn signaled to EMTs that she was playing a deceased passenger, she received a brief apology before they moved on to victims who could still be treated.

Volunteers whose roles were beyond medical help awaited a second visit from the coroner’s office. Once the drill concluded, emergency personnel ferried participants back to the airport tarmac on ATVs.

Kovatch said the community response has been so strong that the volunteer list for the upcoming drill is full.

“It can be pretty hard to get 150 to 175 people together,” he said. “The callouts for volunteers have really helped.”

Holland said she wouldn’t mind participating in another simulation, though she may have to wait until 2029 for the next exercise.

“It was an interesting and fun evening,” she said. “If we can possibly do it, we’ll do it again.”

The drill is scheduled for 6 p.m. Wednesday at the airport. Kovatch said volunteers will receive instructions in advance regarding parking and arrival procedures.