I thought about it some more and went back and reread the NTSB report. It
would appear that they were relying on the INFORMATION (CDI & DME) from the
GPS, but were not looking at the positional display. If they missed the fact
that they had passed the FAF as part of their aborted hold, AND they missed
the fact that the GPS had sequenced to the MAP, then they flew inbound on
the localizer course thinking they were still outside the FAF. The GPS would
be giving them distance information to MAP - they were seeing it as distance
to FAF. They then flew a pretty good approach - just displaced by 5-6 miles.
They also were pretty obviously navigating by the GPS and not using the
primary NAV - or they were at least depending on GPS for DME and not using
an independent DME. I am not familiar with the King GPS - the Garmin 530 has
a big identifier up on top which shows the waypoint being flown to.

The really scary thing is if two pilots with these qualifications can make
such a mistake, what hope is there for me?
"Don Poitras" wrote in message
...
pgbnh wrote:
Not clear (to me at least) is WHY they so clearly lost situational
awareness. Based on when they descended to MDA,and when and how they flew
the missed, they obviously thought they were someplace other than where
they
were.
But why? Missing the fact that they autosequenced over the NDB might have
caused some confusion when flying the hold, but once inbound, both the
GPS
(if they were using it) and the primary nav (presumedly tuned to the LOC
frequency) would both be showing dme to MAP. The gps would count down to
zero, the primary nav would go down to 1. How could either relying on a
potentially unreliable GPS OR missing the autosequencing have caused them
to
to fly several miles PAST the MAP thinking that they had not yet reached
it?
IIRC, they descended to MDA several miles PAST the MAP. They used the MAP
as
the FAF, and seemed to fly a picture perfect approach thereafter. How
could
misreading the GPS or NAV cause this??

I'd guess they weren't looking at the DME. The countdown to the FAF and
the
countdown to the MAP don't look any different except for the waypoint
name.

Once past what they thought was the FAF, they probably set a normal
descent
rate, looked at the localizer needle for course, altimeter for MDA and out
the window for the runway and never looked at the GPS again.

--
Don Poitras