If the vehicle is closer to the launcher, carrier or interfacing system than the minimum safe distance for engine firing, there shall be at least three independent electrical inhibits that control the opening of the flow control devices. The electrical inhibits shall be arranged such that the failure of one of the electrical inhibits will not open more than one flow control device.If the isolation valve will be opened under the conditions of paragraph 201.4.4.1(b), prior to the vehicle achieving a safe distance for firing a large thruster, three independent electrical inhibits shall control the opening of the remaining flow control devices for the large thruster system.
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