The photo of the blown bridge is the Cau Song Be (Song Be bridge) It was taken at about 3,000 feet looking at the bridge from south to north.  It looks as if "Sheriff" Capt. Bob Cocke (see the O-1 strut) was flying east toward Dong Xoai at 3,000 feet and navigating on Route 14 when Steve Adams in the back seat took first the photo of Camp Chi Linh and then the Song Be bridge.