This is the nearer pile of stones, each quite large. From memory I would estimate these to be about 1.8 metres tall. Of course when erect, between a quarter and a third of that could be under the soil.
You can see from the general look of the pictures on these pages that the area has long since ceased to be an airfield. Such a major man made feature now gone without trace, the Stone Circle itself had survived far more than 100 times longer before being destroyed by the military.
This is the second pile of six stones, including some smaller ones. Whether they are true stones or fragments I have no idea. I am only assuming these are the original megaliths from the Devil's Quoits circle, placed there prior to re-erection by archaeologists. I would be fascinated to hear more of the restoration project.