Narrative:

While conducting an instrument checkride in VMC, I sighted a container ship crossing the localizer approach course just east of the threshold for the primary ILS runway at kodiak. The ship cleared the approach path about 40 seconds prior to our arrival at the missed approach point (map) which is charted as 273 ft above touchdown. I also noted that the propeller wake from the vessel was exactly underneath the aircraft when we reached the missed approach point. I subsequently plotted the ILS DME-2 map on the government't nautical chart and discovered that the southern ship channel approach to kodiak harbor crosses the localizer course exactly at the map, exactly when the aircraft is at its lowest point on the approach and possibly still IMC. The owner of the ship estimates his mast height as approximately 125 ft above the waterline at normal draft. This makes the obstacle clearance altitude at the map about 175 ft, depending on altimeter error and pilot situational awareness. Worse, I've noticed other ships with mast heights appearing even higher using the same channel, so the vertical clearance could be even less for unsuspecting pilots flying any of the kodiak instrument approachs for the first time. I have experienced this same event, at night, about 1 year ago. I broke out of IMC about 600 ft MSL on the localizer course and established myself on the VASI - this is absolutely necessary at night because the final 1-2 miles to the airport, depending on the approach, are flown over water, without approach lighting, while departing GS indications as directed on the approach plate ('ILS unusable from D2.0 iadq inbound'). About 20 seconds after becoming VMC on the approach, my visual cues indicated that I was drifting right of course, but the CDI indicated 'on course'. I began scanning a broader area and realized that some of the lights between me and the airport were moving. I then realized that the moving lights were attached to a ship that was crossing the approach path. I purposely veered right of course (the ship appeared to be southwest bound) and cleared the obstacle horizontally while maintaining vertical guidance from the VASI because the ILS DME-2 approach has a warning block on it stating 'any go around commenced after passing the missed approach will not provide standard obstruction clearance.' anyone familiar with the topography around kodiak airport knows that transport category aircraft are pretty much 'committed' to landing within 1 mile of the airport when landing on runways 25 or 29 because of rapidly rising terrain immediately surrounding those runways on the south, west, and north sides of the airport. Kodiak tower sometimes offers de-confliction advisories when they see large vessels off of the approach end of runway 25, but I don't believe the tower personnel can offer consistent, reliable advisories because visibility from the tower to the ship channel can be severely impaired for long periods of time. Additionally, kodiak tower is not manned continuously. Therefore, I recommend that a warning block be annotated on all instrument approach procedure to kodiak airport stating something similar to the following: 'caution: large vessels with mast heights of at least 125 ft regularly transit the ship channels underlying the instrument and visual approach paths to runways 25 and 29. Standard vertical obstruction clearance can be significantly reduced while approaching the airport and maneuvering to land while vessels are present.' I further recommend that this statement also be placed in the 'airport remarks' section of respective supplemental flying information publications. I did not look specifically for any localizer, GS, or DME signal interference while the ship was crossing the approach course, but if there is a possibility of that, I further recommend that some sort of additional statement be published on the approachs warning pilots of this danger.

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Original NASA ASRS Text

Title: RPTR ADVISES SHIPS PASSING THROUGH APCH PATH AFTER MAP ON WESTBOUND ARRIVAL TO ADQ CONSTITUTE POTENTIAL HAZARD BOTH AS AN OBSTACLE AND BY VIRTUE OF THEIR POTENTIAL TO CAUSE A LATE MISSED APCH, WHICH IS NOTED ON THE IAP AS HAZARDOUS DUE TO NON STD OBSTRUCTION CLRNC.

Narrative: WHILE CONDUCTING AN INSTRUMENT CHECKRIDE IN VMC, I SIGHTED A CONTAINER SHIP CROSSING THE LOC APCH COURSE JUST EAST OF THE THRESHOLD FOR THE PRIMARY ILS RWY AT KODIAK. THE SHIP CLEARED THE APCH PATH ABOUT 40 SECONDS PRIOR TO OUR ARRIVAL AT THE MISSED APCH POINT (MAP) WHICH IS CHARTED AS 273 FT ABOVE TOUCHDOWN. I ALSO NOTED THAT THE PROP WAKE FROM THE VESSEL WAS EXACTLY UNDERNEATH THE ACFT WHEN WE REACHED THE MISSED APCH POINT. I SUBSEQUENTLY PLOTTED THE ILS DME-2 MAP ON THE GOV'T NAUTICAL CHART AND DISCOVERED THAT THE SOUTHERN SHIP CHANNEL APCH TO KODIAK HARBOR CROSSES THE LOC COURSE EXACTLY AT THE MAP, EXACTLY WHEN THE ACFT IS AT ITS LOWEST POINT ON THE APCH AND POSSIBLY STILL IMC. THE OWNER OF THE SHIP ESTIMATES HIS MAST HEIGHT AS APPROX 125 FT ABOVE THE WATERLINE AT NORMAL DRAFT. THIS MAKES THE OBSTACLE CLEARANCE ALT AT THE MAP ABOUT 175 FT, DEPENDING ON ALTIMETER ERROR AND PLT SITUATIONAL AWARENESS. WORSE, I'VE NOTICED OTHER SHIPS WITH MAST HEIGHTS APPEARING EVEN HIGHER USING THE SAME CHANNEL, SO THE VERT CLEARANCE COULD BE EVEN LESS FOR UNSUSPECTING PLTS FLYING ANY OF THE KODIAK INSTRUMENT APCHS FOR THE FIRST TIME. I HAVE EXPERIENCED THIS SAME EVENT, AT NIGHT, ABOUT 1 YEAR AGO. I BROKE OUT OF IMC ABOUT 600 FT MSL ON THE LOC COURSE AND ESTABLISHED MYSELF ON THE VASI - THIS IS ABSOLUTELY NECESSARY AT NIGHT BECAUSE THE FINAL 1-2 MILES TO THE ARPT, DEPENDING ON THE APCH, ARE FLOWN OVER WATER, WITHOUT APCH LIGHTING, WHILE DEPARTING GS INDICATIONS AS DIRECTED ON THE APCH PLATE ('ILS UNUSABLE FROM D2.0 IADQ INBOUND'). ABOUT 20 SECONDS AFTER BECOMING VMC ON THE APCH, MY VISUAL CUES INDICATED THAT I WAS DRIFTING R OF COURSE, BUT THE CDI INDICATED 'ON COURSE'. I BEGAN SCANNING A BROADER AREA AND REALIZED THAT SOME OF THE LIGHTS BETWEEN ME AND THE ARPT WERE MOVING. I THEN REALIZED THAT THE MOVING LIGHTS WERE ATTACHED TO A SHIP THAT WAS CROSSING THE APCH PATH. I PURPOSELY VEERED R OF COURSE (THE SHIP APPEARED TO BE SOUTHWEST BOUND) AND CLEARED THE OBSTACLE HORIZLY WHILE MAINTAINING VERT GUIDANCE FROM THE VASI BECAUSE THE ILS DME-2 APCH HAS A WARNING BLOCK ON IT STATING 'ANY GAR COMMENCED AFTER PASSING THE MISSED APCH WILL NOT PROVIDE STD OBSTRUCTION CLRNC.' ANYONE FAMILIAR WITH THE TOPOGRAPHY AROUND KODIAK ARPT KNOWS THAT TRANSPORT CATEGORY ACFT ARE PRETTY MUCH 'COMMITTED' TO LNDG WITHIN 1 MILE OF THE ARPT WHEN LNDG ON RWYS 25 OR 29 BECAUSE OF RAPIDLY RISING TERRAIN IMMEDIATELY SURROUNDING THOSE RWYS ON THE SOUTH, WEST, AND NORTH SIDES OF THE ARPT. KODIAK TWR SOMETIMES OFFERS DE-CONFLICTION ADVISORIES WHEN THEY SEE LARGE VESSELS OFF OF THE APCH END OF RWY 25, BUT I DON'T BELIEVE THE TWR PERSONNEL CAN OFFER CONSISTENT, RELIABLE ADVISORIES BECAUSE VIS FROM THE TWR TO THE SHIP CHANNEL CAN BE SEVERELY IMPAIRED FOR LONG PERIODS OF TIME. ADDITIONALLY, KODIAK TWR IS NOT MANNED CONTINUOUSLY. THEREFORE, I RECOMMEND THAT A WARNING BLOCK BE ANNOTATED ON ALL INST APCH PROC TO KODIAK ARPT STATING SOMETHING SIMILAR TO THE FOLLOWING: 'CAUTION: LARGE VESSELS WITH MAST HEIGHTS OF AT LEAST 125 FT REGULARLY TRANSIT THE SHIP CHANNELS UNDERLYING THE INST AND VISUAL APCH PATHS TO RWYS 25 AND 29. STD VERT OBSTRUCTION CLRNC CAN BE SIGNIFICANTLY REDUCED WHILE APCHING THE ARPT AND MANEUVERING TO LAND WHILE VESSELS ARE PRESENT.' I FURTHER RECOMMEND THAT THIS STATEMENT ALSO BE PLACED IN THE 'ARPT REMARKS' SECTION OF RESPECTIVE SUPPLEMENTAL FLYING INFO PUBLICATIONS. I DID NOT LOOK SPECIFICALLY FOR ANY LOC, GS, OR DME SIGNAL INTERFERENCE WHILE THE SHIP WAS CROSSING THE APCH COURSE, BUT IF THERE IS A POSSIBILITY OF THAT, I FURTHER RECOMMEND THAT SOME SORT OF ADDITIONAL STATEMENT BE PUBLISHED ON THE APCHS WARNING PLTS OF THIS DANGER.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.