After 42 seconds of flight, the rules of what would happen in case of an abort changed slightly to take account of the fact that the space vehicle had tilted over substantially and had also gained plenty of horizontal speed. The mission had moved into abort mode one-bravo which lasted until it reached an altitude of 30.5 kilometres. If an abort were to be called during this period, the escaping command module would no longer be in danger of falling into the Saturn's debris, and the small motor intended to steer it out to sea would no longer be required. What was needed,
however, was a way to ensure that the CM would turn to face the correct direction after being pulled from an aborting Saturn. This was because tests had shown that at hypersonic speeds, it was possible for the CM/escape tower combination to be stable in a nose-first attitude. The tower could not be safely jettisoned in this mode because the airflow would ram the boost protective cover onto the CM hull, which would not only prevent the tower pulling away but also prevent the parachutes from deploying. Once the escape tower had pulled an aborting spacecraft free in a one-bravo abort, two skin sections near the top of the escape tower, known as canards, would deploy after the launch escape motor had done its job, creating drag and thereby forcing a turn-around manoeuvre, if one were needed, to face the heatshield in the direction of travel, and allow deployment of the parachutes.
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