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Why is not required to check for RAIM with a WAAS GPS?

Asked by: 2820 views Instrument Rating

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2 Answers



  1. Bryan on Jun 08, 2022

    John Collins gave a great answer to this in March 2020: https://www.askacfi.com/34817/lose-raim-but-we-have-waas-can-you-shoot-the-gps-approach.htm

    In short, the two systems monitor integrity differently. Checking RAIM tells you nothing about WAAS integrity and vice-versa.

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  2. John D Collins on Jun 09, 2022

    The WAAS signal includes the integrity information. The standard GPS signal does not include the integrity information, so RAIM is an algorithm that uses additional satellites to determine integrity of the position. Integrity is a measure of the trustworthiness of the position.

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