NavList:

Doing celestial navigation in flight has clearly defined standards for accuracy listed in Federal Regulation, 14 CFR 63 and are tested for issuance of a Flight Navigator's Certificate. On the ground the applicant has to take a series of ten shots, none of which can be in error greater than 8 minutes and the average error cannot exceed 5 minutes and also a three star fix that must plot within 5 NM of the actual position. Then, while flying, the applicant takes hourly fixes all of which must plot within 10 NM of the actual positions which requires that all the observations must be within 7 minutes of arc (thank ol' Mister Pythagoras for that) and this is sufficient accuracy for flight navigation. The applicant also has to compute accurate ETA's to checkpoints none of which can be in error more than 10% of the time interval (6 minutes on an hour leg) and the average can't exceed 5% (3 minutes on an hour leg.) Something similar could be developed for marine navigation with more precise standards.

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