Narrative:

I was on a reposition flight, iad to ewr. I was told to expect ILS runway 22L at ewr. At the last min I was told to expect GPS runway 11 approach and descend to 3000 ft. The ILS runway 11 was inoperative. I pounded in the GPS runway 11 approach, or thought I did. I was rushed for time, as this was a single pilot operation. The GPS was not taking the approach. I discovered that I had only put in the GPS flight plan to the metropolitan intersection and not all the way to ewr. That is why GPS was not taking the flight plan. I punched in direct ewr, set up obs for 107 degrees, selected approach. Approach arm light came on. The GPS did not sequence through the approach fixes, but I knew the distance to airport, so descended to MDA at distance of FAF. WX was reported as 700 ft broken and 7 mi. It was more like 620 ft and 3 mi. I broke out just above MDA, but instead of seeing end of runway 11 I was looking at ewr control tower. I made left turn to base leg and landed on runway 11 without incident. I was at least 1/4 mi off course although the HSI needle was centered. Upon reconsideration of events I realize what happened. I did not get clearance until 'ready to taxi' at iad. When I got clearance I was in a rush to program the GPS. In my rush I did not program all the way to ewr but only to metropolitan intersection. This would not normally be a problem as one usually gets radar vectors to the final approach course with ILS approach. The approach selection page would not come up on the 'active' page of the GPS because the flight plan ended at metropolitan intersection and not ewr. The approach selection page came up in 'airport' when in direct to ewr but would not become active because I was too close to FAF. In obs mode 107 degrees to ewr, the GPS took me to the center of airport and not runway 11, and would not sequence to approach. When the GPS did not do what I expected I should have told controller I was unable to do GPS, and either do ILS or get vector away from the airport to sort out the GPS problem. Contributing factors other than pilot: change of approach close to airport. Delay in getting clearance at iad until 'ready to taxi,' and having to hurry in programming the GPS. GPS manual says trying to join approach course inside of 2 mi from FAF 'may result in a failure of the unit to activate on the approach.' controllers need to be aware of this limitation of GPS and FMS system.

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Original NASA ASRS Text

Title: A CESSNA 208 PLT REVIEWS THE REASONS HE BROKE OUT OF THE CLOUDS AT EWR BELOW THE RPTED CEILING FACING THE CTL TWR INSTEAD OF BEING LINED UP ON RWY 11 AS HE EXPECTED.

Narrative: I WAS ON A REPOSITION FLT, IAD TO EWR. I WAS TOLD TO EXPECT ILS RWY 22L AT EWR. AT THE LAST MIN I WAS TOLD TO EXPECT GPS RWY 11 APCH AND DSND TO 3000 FT. THE ILS RWY 11 WAS INOP. I POUNDED IN THE GPS RWY 11 APCH, OR THOUGHT I DID. I WAS RUSHED FOR TIME, AS THIS WAS A SINGLE PLT OP. THE GPS WAS NOT TAKING THE APCH. I DISCOVERED THAT I HAD ONLY PUT IN THE GPS FLT PLAN TO THE METRO INTXN AND NOT ALL THE WAY TO EWR. THAT IS WHY GPS WAS NOT TAKING THE FLT PLAN. I PUNCHED IN DIRECT EWR, SET UP OBS FOR 107 DEGS, SELECTED APCH. APCH ARM LIGHT CAME ON. THE GPS DID NOT SEQUENCE THROUGH THE APCH FIXES, BUT I KNEW THE DISTANCE TO ARPT, SO DSNDED TO MDA AT DISTANCE OF FAF. WX WAS RPTED AS 700 FT BROKEN AND 7 MI. IT WAS MORE LIKE 620 FT AND 3 MI. I BROKE OUT JUST ABOVE MDA, BUT INSTEAD OF SEEING END OF RWY 11 I WAS LOOKING AT EWR CTL TWR. I MADE L TURN TO BASE LEG AND LANDED ON RWY 11 WITHOUT INCIDENT. I WAS AT LEAST 1/4 MI OFF COURSE ALTHOUGH THE HSI NEEDLE WAS CTRED. UPON RECONSIDERATION OF EVENTS I REALIZE WHAT HAPPENED. I DID NOT GET CLRNC UNTIL 'READY TO TAXI' AT IAD. WHEN I GOT CLRNC I WAS IN A RUSH TO PROGRAM THE GPS. IN MY RUSH I DID NOT PROGRAM ALL THE WAY TO EWR BUT ONLY TO METRO INTXN. THIS WOULD NOT NORMALLY BE A PROB AS ONE USUALLY GETS RADAR VECTORS TO THE FINAL APCH COURSE WITH ILS APCH. THE APCH SELECTION PAGE WOULD NOT COME UP ON THE 'ACTIVE' PAGE OF THE GPS BECAUSE THE FLT PLAN ENDED AT METRO INTXN AND NOT EWR. THE APCH SELECTION PAGE CAME UP IN 'ARPT' WHEN IN DIRECT TO EWR BUT WOULD NOT BECOME ACTIVE BECAUSE I WAS TOO CLOSE TO FAF. IN OBS MODE 107 DEGS TO EWR, THE GPS TOOK ME TO THE CTR OF ARPT AND NOT RWY 11, AND WOULD NOT SEQUENCE TO APCH. WHEN THE GPS DID NOT DO WHAT I EXPECTED I SHOULD HAVE TOLD CTLR I WAS UNABLE TO DO GPS, AND EITHER DO ILS OR GET VECTOR AWAY FROM THE ARPT TO SORT OUT THE GPS PROB. CONTRIBUTING FACTORS OTHER THAN PLT: CHANGE OF APCH CLOSE TO ARPT. DELAY IN GETTING CLRNC AT IAD UNTIL 'READY TO TAXI,' AND HAVING TO HURRY IN PROGRAMMING THE GPS. GPS MANUAL SAYS TRYING TO JOIN APCH COURSE INSIDE OF 2 MI FROM FAF 'MAY RESULT IN A FAILURE OF THE UNIT TO ACTIVATE ON THE APCH.' CTLRS NEED TO BE AWARE OF THIS LIMITATION OF GPS AND FMS SYS.

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.