Abstract
By continuous circling technique, 35 mm. air photo records were made during 10 peak hours on two sections of an urban freeway. 5 on a four-lane, ,and 5 on a three-lane out bound section. Speeds, time headways, distance headways, and response times were analysed from samples selected from the 1000 ft of projected films to include deceleration waves. Each example included from 40 to 150 pictures spaced 1 sec. apart yielding 20 to 30 individual measurements for a total of 3000 to 4500 in each sample.