In addition, Atlas 3B could not be cleared for flight until a successful firing run of Missile 2B was performed at the Sycamore Canyon test stand, which was also experiencing nonstop technical issues.

Even before the flight had terminated, real time telemetry readouts clearly indicated that the fault lay in the yaw gyro motor, which was not running.

A minor thrust section fire was evident from T+9 seconds, caused by placement of the lube oil vent line near the booster turbine exhaust, however this was believed to have no connection to the subsequent loss of the missile.

[2] On Missile 4B, the location of the lube oil vent lines was moved, and improved heat insulation added to the firewall and engine boots.

The first involved high vibration levels following BECO; this was corrected by a few modifications to the autopilot, as well as moving the rate gyros forward slightly to increase their responsiveness to missile bending.

In addition, the guidance system rate beacon experienced difficulties early in the flight, however discreet steering commands were issued properly.

LOX regulator pressure fell off, resulting in gas generator flameout and complete shutdown of both booster engines.

At liftoff, one of the launcher hold-down arms had also not retracted properly, which resulted in holes being torn in the B-1 thrust structure, however this was quickly ruled out as a cause of the failure.

After the failure of Atlas 15A to a turbopump problem in April, the Air Force agreed to a fix for the oil foaming issue by changing the pressure in the gearbox and using a different viscosity of oil but rejected the idea of outright replacing the pumps with the newer model Rocketdyne had developed even though it would have only taken a month to replace the old pumps.

Roll control was extremely poor for the first 44 seconds of launch, resulting in excessive movements of the booster engines and verniers to maintain missile stability.

On the evening of December 18, Missile 10B performed the first use of an Atlas for a space launch when it orbited SCORE, a prototype communications satellite.

The missile was also stripped down to save weight—the Azusa tracking system, telemetry packages, and all other hardware not absolutely essential to the flight were removed.

SCORE transmitted a tape-recorded Christmas greeting from President Eisenhower and operated for 13 days until the batteries ran down.

With a combined weight of 8,660 pounds (3,930 kg), it held the record for largest artificial object in space for a number of years.

A backup command from the guidance system at T+138 seconds corrected it, and the malfunction was believed to be due to a slight misalignment of the gyro canister.

Starting at T+100 seconds, the engines began gimbaling in all three axes, resulting in complete loss of control and missile tumbling.

The Atlas B test program concluded with the successful flight of Missile 11B on February 4, which reached an apogee of 610 miles (980 km).