I had lunch today with some retired airline pilots. One gent brought in a 1970 Airline Pilot's Association (ALPA) magazine. In it there was this photo of an Allen Green 1969 Camaro (maybe ZL1?) towing a device to measure runway friction in Seattle. This was only a photo with a Pan Am 747 in the back ground and the caption below; no other info. This is right around the time the 747 was getting release for service.
I think you'll enjoy this tidbit if this hadn't been discussed already.
Phil Woj.
The magazine the photo was in: