I was in flight lead of a flight of 2 UH-60M’s conducting a cross country flight on the east coast returning from picking up brand new aircraft. We were on the final leg for the day under day VMC conditions. We had just passed a small airport with a control tower heading south. The forecast weather for the day was VMC all day and the tower controller at the small airport had just given another aircraft an unofficial weather brief that confirmed the VMC conditions. Approximately 10 miles south of the airfield we entered an un-forecasted snowstorm. Initially we slowed to approximately 80 KIAS and descend to 300 feet. We could see tree tops but no suitable landing areas. As a flight we discussed turning around and decided that Chalk 2 should turn first to prevent us from turning into them. Chalk 2 began a turn but started to become disoriented and decided to stop their turn to rejoin the formation for Chalk 1. As weather deteriorated I quickly looked up the closest approach control facility and programmed the frequency into the radio. As visibility continued to decrease we decided to commit to IMC and execute our IIMC plan. We announced over our air to air frequency that we were going inadvertent and Chalk 2 announced they were going inadvertent with us. I was not on the controls but I came inside to look at the attitude indicator and noticed we were in a slight right turn. The crew chief in the back had turned his seat forward and noticed the same thing and announced “your wings are not level.” The pilot on the controls then announced, ” I have visual on Chalk 2.” I looked up and Chalk 2 flew past us and turned right in front of us and continued right. I lost them in the snowstorm and the pilot on the control rolled wings level and began a climb. Once our climb was established and the aircraft was under control I called approach control and requested an IFR clearance to our destination. The pilot on the controls began coupling the aircraft to the flight director to reduce workload. We were immediately given a squawk and vectors to do an ILS into our destination.
Chalk 2 began calling on guard and declared an emergency stating that they were Inadvertent IMC. The first station to call them back was a flight service station. Flight service then passed them to the approach control facility. Approach control was initially confused by the emergency declaration and confused by our call signs since they already had one aircraft with a similar call sign (us) that had declared inadvertent IMC. After multiple communications back and forth approach control gained understanding of what had happened and gave Chalk 2 a squawk and vectors for the ILS. Both aircraft returned single ship and completed the ILS, breaking out at approximately 400 feet. A Coast Guard JayHawk had run into the same weather further east of us and had initially tried to return SVFR before also making the determination to proceed Inadvertent IMC. Lessons Learned
What went wrong – the IIMC multi-ship procedure did not go as briefed or planned. Chalk 2 did not adhere to the procedure and put both aircraft in a dangerous position. Chalk 1 did not announce the other aircraft being inadvertent upon initial contact with ATC resulting in confusion at a critical time in the flight.
What went right – both crews committed to IMC when they realized weather conditions were continuing to degrade and a suitable landing area was not available. Chalk 1 knew who they would talk to if they went inadvertent resulting in faster ATC service. Training beginning in flight school and continued at the unit resulted in both crews not being afraid to commit to IMC when needed and to be proficient at IFR procedures. Training of crew chiefs to focus attention inside during IMC and know what to look at to assist in helping pilots maintain aircraft control. Both crews had all the necessary publications readily available to execute the approach to complete the flight.