Airmen and Space Force Guardians are being encouraged to apply for prep classes to get ready for Army Ranger School, the incredibly difficult tactics course with a historically low graduation rate.

The Department of the Air Force, in a recent press release, said it is searching for members from both services to enroll in the grueling course and encouraged them to take the leap.

“It’s been called ‘a laboratory of human endurance,’ testing the physical, mental and spiritual grit of the officer and enlisted leaders who undertake it,” the Air Force said in the release. “It’s the Army Ranger School, and the Department of the Air Force is looking for airmen and Guardians who are ready for the challenge.”

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The 62-day course is filled with difficult physical training and exercises designed to educate participants on elite squad and platoon tactics. During Ranger Assessment Phase week at Ranger School, candidates must complete 49 push-ups, 59 sit-ups, a five-mile run in 40 minutes, and six chin-ups, according to the Air Force. It ends with a 12-mile march with each candidate carrying roughly 35 pounds.

Each year, an estimated 4,000 candidates attempt the program. The Air Force first began sending airmen to Ranger School in 1955; since then, around 350 have graduated from the course, according to the service.

Roughly 40% of service members who attempt Ranger School graduate, the service said. To help prepare, the Air Force developed a type of Ranger Assessment Course in the mid-1980s in an attempt to send the best candidates who were most likely to succeed.

The next Air Force Ranger Assessment Course, or RAC, is set for early spring at Joint Base San Antonio-Camp Bullis, Texas, according to the service, and airmen and Guardians from any career field can attend the 19-day prep school.

“While the majority of Ranger School attendees come from combat arms career fields, individuals from other Air Force specialty codes can also attend if they meet the necessary prerequisites and requirements,” Gabriel Rodriguez, readiness training and RAC program manager at the Air Force Security Forces Center, said in the release.

Last year, for the first time ever, a Space Force Guardian also graduated from the two-month course, clearing the requirements of the physical training and exercises.

Capt. Daniel Reynolds, with the 4th Test and Evaluation Squadron out of Peterson Space Force Base, Colorado, graduated from Ranger School at Fort Moore, Georgia, in October.

Reynolds graduating from Ranger School was not only a first for the Space Force, but bucked criticisms and stereotypes that Guardians aren’t as active as members of the other military service branches.

Reynolds encouraged Guardians and airmen to think long and hard on why they’d want to attend.

“A significant proportion of people who fail the course do so because they arrived without deciding that the experience was something that their life needed,” Reynolds said in the release. “Take the time to decide for yourself what your reasons for Ranger School are, and how important joining the community is to you. When you’re more cold, wet, tired and hungry than you’ve ever been in your life, those reasons will be what you will lean on to carry you through.”

Related: Guardian Gets Ranger Tab in First-Ever Achievement for Space Force

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