Spacecraft ground test plans had been formulated, and the construction of test hardware had begun.

Two boilerplate spacecraft had been added to the program to facilitate ground testing. Flight No. 2 was the first planned to use paraglider, but the paraglider program required close attention to prevent schedule slippage; plans to substitute a parachute landing system for paraglider in this flight, should it prove necessary, had been initiated. Spacecraft manufacturing schedules were endangered by late delivery of components from vendors: chief threats to spacecraft No. 1 were components of the instrument and recording system and the inertial platform; for spacecraft No. 2, communication and electrical system components. No problems were anticipated with the booster. The analysis indicated no change in the launch schedule.