CONTINGENCY OPERATING BASE SPEICHER, Iraq — They boarded the bus in the dark Sunday morning, rubbing the sleep from their eyes and preparing for the day’s mission.

Within a few hours, more than 20 soldiers from the Keene-based 220th Transportation Company would set off in a convoy through the Iraq desert.

The day’s mission was to carry nine Mine Resistant Ambush Protected vehicles, or MRAPS, and a few containers filled with supplies from the base in Tikrit to Forward Operating Base Marez in Mosul.

It was one of the unit’s largest vehicle transport missions in the four months since it arrived in Iraq in July, according to convoy commander Staff Sgt. Robert Short of North Andover, Mass.

After the bus lurched to a stop at the Army Reserve unit’s motor pool, the soldiers stepped out into the crisp air and made their way to the line of waiting trucks.

The smell of diesel wafted by as the trucks rumbled to life and a brilliant strip of red in the pre-dawn sky slowly grew along the horizon.

“Let’s get it going,” Short shouted to a driver over the din of the vehicles.

As convoy commander, his job overseeing the operation kept him busy marching between vehicles to check in with drivers.

The MRAPS were already loaded onto nine large trucks, known as Heavy Equipment Transporter Systems, or HETS, which pull 40-wheel trailers designed to haul tanks and other large military vehicles.

But it would still take a few hours of preparation before the trucks would be ready to leave.

By 7 a.m., the truck drivers completed maintenance checks and began moving the trucks across the base to an area known as the staging lanes. It’s here that convoys, which frequently consist of a combination of military transportation units, military security vehicles also called “gun trucks” and tractor-trailer trucks owned by civilian contractors, assemble.

The massive trucks from the 220th formed two lines between rows of concrete blocks. Now, it was time to wait.

As drivers climbed down from the trucks, they made last-minute preparations, such as wiping down windshields and checking tires. Each truck is manned by a driver and truck commander whose job is to man the radio that allows each vehicle in the convoy to communicate with the others.

Spc. Matthew Smyrski of Ira, Vt., climbed into the driver’s seat of his truck and filled a cooler behind him with ice from bags dropped off by support soldiers in the unit.

Smyrski, who has been with the 220th for four years, said he prefers to drive the HETS over the tractor-trailer trucks the unit also operates.

“There’s more room,” he said. “They’re more comfortable to drive and there’s two beds in the back in case you have to stop somewhere and need to sleep.”

While Sgt. Stephen Rhodes of Brooklyn, N.Y., waited for the convoy to take off, he pulled out a digital camera and posed for a few photos next to the truck he was driving.

Rhodes and several other members of the 220th transferred into unit from the N.Y.-based 773rd Transportation Company shortly before the deployment. Soldiers in the unit also come from California, Connecticut, Florida, Maine, Maryland, Massachusetts, Michigan, New Jersey and Pennsylvania.

About 8:30 a.m., after convoy security vehicles from the Louisiana National Guard’s A Company, 3rd Battalion, 156th Infantry Regiment arrived, the convoy set off.

Up next, Farrar writes about traveling with a convoy in Iraq.