第三条本规定所称不定期飞行，是指不属于定期航班的民用航空运输飞行。

Article 3. For the purpose of these Regulations, "irregular flight" means flight in civil air transportation which does not belong to any regular air service.

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第四条从事不定期飞行，必须向中国民用航空局申请，经批准后方可飞行。

Article 4 the operation of non-scheduled flights shall be subject to the submission on an application to the Civil Aviation Administration of China (CAAC) for its approval.

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