TMetzinger
Final Approach
in this month's IFR quiz, they dissect the KMTN VOR DME 15 approach, which is a fun arc approach.
One of the questions (#11) indicates that an IFR approach GPS can't be used to substitute for DME on the approach, but the current AIM says that flying a DME arc is one of the things that CAN be done with IFR GPS. I asked the editor to get the authors to elaborate.
I'm aware there's an email from AFS-400 out there somewhere that says basically "we didn't really mean what we said in the AIM when it comes to approaches", because the AIM states that it can't be used as the principal nav source i.e lateral guidance.
The problem I have with that is that any arc will use distance for lateral guidance, whether it's part of the final approach course, a lead-in to an approach, a missed, something enroute, whatever. You look at your distance and turn left or right based on that.
Has there been any "final" word from FAA chief counsel on this yet? One email does not make policy.
This is almost as bad as the "interpretations" we got from John Lynch (no ire here - he was flat out doing his best) on the part 61 rewrite, several of which were flat out contradicted by the chief counsel when a formal opinion was sought.
One would think if there was a policy change in summer 2005 it would have made it into the AIM by 2006, or as an SFAR or something.
One of the questions (#11) indicates that an IFR approach GPS can't be used to substitute for DME on the approach, but the current AIM says that flying a DME arc is one of the things that CAN be done with IFR GPS. I asked the editor to get the authors to elaborate.
I'm aware there's an email from AFS-400 out there somewhere that says basically "we didn't really mean what we said in the AIM when it comes to approaches", because the AIM states that it can't be used as the principal nav source i.e lateral guidance.
The problem I have with that is that any arc will use distance for lateral guidance, whether it's part of the final approach course, a lead-in to an approach, a missed, something enroute, whatever. You look at your distance and turn left or right based on that.
Has there been any "final" word from FAA chief counsel on this yet? One email does not make policy.
This is almost as bad as the "interpretations" we got from John Lynch (no ire here - he was flat out doing his best) on the part 61 rewrite, several of which were flat out contradicted by the chief counsel when a formal opinion was sought.
One would think if there was a policy change in summer 2005 it would have made it into the AIM by 2006, or as an SFAR or something.