Henry Rifle Forums

https://www.military.com/daily-news/202 ... tucky.html

Night formation flying I am betting. Always a dangerous endeavor. One little mistake, and tragic results ensue. A sad time for the 101st.

It would appear that it was a mid air. The witness said they were flying low and in very close formation.
In my Army time I flew in a lot of this type of thing and it was always risky.
My condolences to the families and friends of the victims.