Tuesday, March 17, 2009

Seattle - Astoria - Seattle / Beechcraft Bonanza A36 (N6835W) / IFR

The flight out to the small airport of Astoria, Oregon, on the Pacific coast, was largely uneventful. I took off from 16R at KSEA and rapidly headed southwest to CARRO, then to the Olympia VOR, then straight out on V187 to Astoria. My initial altitude for this IFR flight was 4000, and I requested and obtained 6000 after I was well clear of the Seattle Class B.

The interesting part arose as I neared Astoria. The approach plate for the ILS runway 26 approach mystified me. There was no ATC coverage by this time, so I had to negotiate the arrival and approach myself. I continued on V187 until I was a dozen miles or so east of the field. But then I wasn't sure what to do. Should I fly to AST, turn around, fly to the NDB, then descend and make a procedure turn to capture the ILS and come on in to runway 26? Or should I turn north and take the DME arc back to the ILS and come in that way. There are three IAFs on the plate, one at the NDB that sits on the ILS path, and two at the ends of two DME arcs 19 nm from AST.

Turning around twice seemed awkward, so I decided to fly out towards the northern DME arc and join the IAP there. The MSA was 4300, and I had begun descending as soon as I was within 25 nm of AST, so I was at about 4300 before reaching the arc, and once on the arc, I descended further to the suggested 4000 feet. It was a challenge to hold the arc but I did okay. As I approached the ILS localizer centerline, I turned to the west and armed the AP for the approach, which it immediately captured. The approach thereafter was routine, with me turning off the AP about a mile out of the field and completing the landing by hand in slightly gusty winds.

I'm trying to find out how this procedure should be flown. I tried asking about it on a newsgroup, but that was the usual waste of time because there are very few qualified instrument pilots on the group, and lots of noisemakers. I'll try asking in some other venues. The documentation I have (FAA manuals and such) don't make it clear how I should fly this, or I've missed the relevant passages. I've included a picture of the plate here (it's government-issued, not copyrighted) in case anyone would like to send me feedback with suggestions.

Later I flew back from Astoria to SeaTac, but that was easy. I proceeded in over OLM and received the Elliot Visual, which was pleasant to fly. I parked over in the transient area now that the new runway area is finished (I've also routinely parked in the cargo area north of the tower, but it looks like GA aircraft are expected to be in the transient area instead.)