FORT RUCKER, Ala. (April 29, 2019) - During a deployment to Iraq, I was flying UH-60s as part of a medevac company operating out of Forward Operating Base Echo in Diwaniyah. It was common for us to conduct routine patient transfer missions from FOB Echo to Baghdad or Balad. On this particular evening, we were transferring a patient as a flight of two Black Hawks to Baghdad to facilitate a higher level of care. Little did we know a number of events would unfold that almost cost us our lives.We checked weather and maintenance to ensure a trouble-free flight. The aircraft were sound and the weather prediction was predominately clear. However, the briefer said they expected the dust to become airborne later in the evening (much later than our estimated time of arrival), thus significantly affecting visibility. With this prediction well outside of our mission parameters, we headed out the door to conduct business as usual.The flight to Baghdad was, for the most part, uneventful. It was a nice, clear night with about a quarter-moon for illumination. We dropped off our patient at the hospital, topped off fuel in the forward arming and refueling point and then headed away from the city on our way back to the FOB.As anyone who has flown in Iraq at night knows, once you navigate away from the city and all of its ground lights, the desert suddenly becomes a vast sea of absolute darkness with very few references for orientation, especially with little illumination. It just so happened that on this night Murphy's law was in full effect. The predicted dust storm began about two hours ahead of schedule, dropping visibility from five or six miles down to about one and a half miles.As a flight of two coming out of Baghdad, my aircraft was trail and I was flying with an experienced instructor pilot in our unit. We both had flown this mission countless times and practically knew the route by memory. As we exited the FARP, we made a left-hand turn to head south to Diwaniyah. While we were turning, we decided to shift from the inside to the outside of the formation.During the turn, a number of events unfolded. The lead aircraft's airspeed indicator malfunctioned, showing 135 knots indicated airspeed, even as the aircraft had slowed to 110 KIAS (120 KIAS was desired). As it happened, my aircraft, still on the inside of the turn, was forced to slow even more aggressively than usual. As the lead flight continued to slow, we had to climb to avoid a collision. We then overtook the lead and, coordinating over the radio, attempted to regain formation flight.As we corrected our climb to establish our briefed altitude, my co-pilot suddenly became disoriented. The aircraft rolled into a 15 to 20 degree left descending bank, losing altitude at a rate of about 400 feet per minute. I made a flight control change and started a climb. Upon rolling out, my co-pilot stated I was now in an unusual attitude.I glanced at the instruments and saw I was in a right descending turn, losing altitude at about 500 fpm and heading again toward the all-too-close desert floor. My co-pilot took the controls back and, once again, established straight-and-level flight. Once the other aircraft fell in behind us, we continued the flight back to base with continued degraded visibility. At one point, we claimed to be losing sight of our rear position light at a distance of four rotor disks. Upon arrival at Diwaniyah, we all realized how close we had come to a complete disaster on what seemed to be such a simple routine mission.Afterward, we held a unit meeting so everyone could listen to our mission after-action report with the goal of preventing another close call like we had. We discussed many points, but the main one was that anyone - regardless of skill level, experience or position - can be a victim of spatial disorientation. Army aircraft are designed as two-pilot aircraft, not because of the position of the power levers or any other rumor we've all undoubtedly heard, but because we operate in harsh environments performing complex missions. It is the complexity of these missions and the unforgiving nature of our operating environment that requires us all to be competent co-pilots for one another.Do you have a story to share? Risk Management is always looking for contributors to provide ground, aviation, driving (both private motor vehicle and motorcycle) and off-duty safety articles. Don't worry if you've never written an article for publication. Just write about what you know and our editorial staff will take care of the rest. Your story might just save another Soldier's life. To learn more, visit https://safety.army.mil/MEDIA/Risk-Management-Magazine.