nddons
Touchdown! Greaser!
I flew the LOC/DME RWY 36 approach this afternoon http://204.108.4.16/d-tpp/1003/05231LD36.PDF and had an interesting discovery.
I fly a 172R with a King GPS, which I used for my DME information. That presented no problem, UNTIL I attempted to define the FAF. Unlike the VOR/DME RWY 36 approach, which uses the OSH VOR to define the 26 DME arc as well as the FAF, this approach defines the FAF as DME from the localizer antenna. My GPS does not have that point as a fix, so if this was a real approach in IMC, I do not believe I would have been legal to fly this approach, because I could not define the FAF by the navaid.
I used the airport as the navaid just to fly this practice approach in VMC, but learned about the limitations of GPS. In IMC I could have flown the VOR/DME approach to get in to the airport, but didn't realize the limitations of the GPS that I was using. (And yes, the database was current.)
So my question is, would more advanced GPS systems have this fix in the database, or is this a case where you actually must have DME (and not a GPS substitute for DME) to fly the approach?
I fly a 172R with a King GPS, which I used for my DME information. That presented no problem, UNTIL I attempted to define the FAF. Unlike the VOR/DME RWY 36 approach, which uses the OSH VOR to define the 26 DME arc as well as the FAF, this approach defines the FAF as DME from the localizer antenna. My GPS does not have that point as a fix, so if this was a real approach in IMC, I do not believe I would have been legal to fly this approach, because I could not define the FAF by the navaid.
I used the airport as the navaid just to fly this practice approach in VMC, but learned about the limitations of GPS. In IMC I could have flown the VOR/DME approach to get in to the airport, but didn't realize the limitations of the GPS that I was using. (And yes, the database was current.)
So my question is, would more advanced GPS systems have this fix in the database, or is this a case where you actually must have DME (and not a GPS substitute for DME) to fly the approach?