Sen. Joni Ernst, R-Iowa, is urging Air Force officials to expand the "mandatory buddy pair system" beyond basic training recruits at Lackland Air Force Base to the trainees at Randolph Air Force Base and Fort Sam Houston.

The three installations are part of Joint Base San Antonio, Texas.

Ernst, a leading voice in congressional efforts to stem military sexual assaults, visited Fort Sam Houston in mid-November to talk with service members about sexual violence and the best way to combat it.

In a Jan. 25 letter to Brig. Gen. Heather Pringle, commander of Joint Base San Antonio and the 502nd Air Base Wing, Ernst wrote she was disappointed to learn the Air Force does not have a mandatory buddy system for all its students in training status, only for basic recruits.

While basic training is conducted at Lackland, many other airmen train for medical specialty codes at Fort Sam Houston, and Randolph hosts flying training.

Recruits at Lackland are assigned a "wingman" on the first day. If trainees need to go anywhere, they must be accompanied by their wingman. Each airman also carries a "wingman card" at all times that includes the name of their wingman and emergency phone numbers for the trainee/student hotline and the sexual assault response coordinator.

The card says, "I will never leave my wingman. I will look out for possible self-harm or unprofessional relationship indicators to my wingman. I have a duty to report any indicators that may hurt my wingman or bring discredit to the United State Air Force."

Ernst said all the other services have a buddy system for all troops in training status. The retired Army lieutenant colonel noted that when she was deployed to Iraq as a captain, everyone on base was required to travel in pairs.

"As we continue to see sexual assault plague institutions around the country, it is my hope that the military will continue to take concrete steps to improve and become a leading example for how to effectively curb this problem, Ernst wrote.

Air Force spokesmen at Joint Base San Antonio said they had not yet see the letter and therefore could not comment.