If you look at the diamond taking off as they are turning around at the end of the runway look just in front of the cockpit when they zoom in.
All the Blue's Super Hornets are low-rate initial production jets. The sensor is the IFF interrogator. The covering is called the "pizza box". The Blue's Super Hornets are a mix of lot 21, 22 & 23 aircraft. The lot 21 aircraft don't have the IFF interrogator.
https://www.youtube.com/watch?v=yvguL4qTqyM