Retired Strike Pig Driver
It is probably more likely just chance that it worked out that way, rather than an intentional scheduling practice.Another Hog question. In this book the average example of the battle sortie for CAS is a section of two airplanes, and the flight lead is almost always Capt, but in a half of cases the wingman is Maj, LtCol, and in one occasion even full O-6, Colonel USAF. Is that the feature of the USAF Hog community solely or NAVAIR single-seaters' flight also can be arranged with the wingman senior to flight lead?
That being said, the reality is that in an average USAF fighter squadron an O-3 is far more likely to be a proficient and current pilot than an O-4 or above. O-4+s are prone to be "attached" to an operational fighter squadron, but may have primary duties for the Group or Wing. As such, they may have less sorties per month and even fewer overall qualifications, leading to them being scheduled as a wingman more often.