From USGS "The National High Altitude Photography (NHAP) program, which was operated from 1980-1989, was coordinated by the U.S. Geological Survey as an interagency project to eliminate duplicate photography in various Government programs. The aim of the program was to cover the 48 conterminous states over a 5-year span. In the NHAP program, black-and-white and color-infrared aerial photographs were obtained on 9-inch film from an altitude of 40,000 feet above mean terrain elevation and are centered over USGS 7.5-minute quadrangles. The color-infrared photographs are at a scale of 1:58,000 (1 inch equals about .9 miles). All NHAP flights were flown in a North to South direction. These photographs are offered as digital images" (https://catalog.data.gov/dataset/nhap-national-high-altitude-aerial-photography-1980-1989 , April 2017). In 2016, Donald W. Hamer Center for Maps & Geospatial Information at The Pennsylvania State University obtained high quality digital images of 9x9 film from USDA - FSA Aerial Photography Field Office (APFO). Digital images were captured at 2,032 dpi with Wehrli and Associates, Inc. RM-6 and RM-3 photogrammetric scanners. The complete collection of 2,607 images contain 60% forward and 30% side to side overlapping coverage for all of Pennsylvania.
Not Georeferenced. Statewide historic aerial images for Pennsylvania. Color-infrared photographs from the National High Altitude Photography (NHAP) program, conducted by the USGS. Pennsylvaina imagery was captured between 03/27/1980 & 05/13/1987.