Maule Driver wrote:


Jim Macklin wrote:


I'm not familiar with the KLN 90B but fly a Garmin 300XL which I believe
is of similar vintage and function. In addition, my single CDI is wired
so that it would auto-connect to the NAV radio when tuned to a LOC signal.

The NTSB indicated that the Pilot's CDI was set up to display NAV even
when GPS was selected on the annunciator. This is typically accomplished
using a multipole relay (like a NAT-80? i think) to enable the NAV
override - its not something switchable on the King Box, its done
downstream. (just fyi.. thats all)



Using the Garmin on such an approach to function in place of the ADF and
DME, I would have programmed it similarly. However, flying the
approach would require switching it from 'auto-sequence' to 'hold' just
before passing BALES for the holding pattern turn. That would keep
BALES as the next waypoint. Once inbound to BALES, I would have
switched it to auto=sequence.

Does the KLN 90B function similarly? That is, is there a Hold switch?

I believe the "OBS" button is used to suspend waypoint sequencing in the
King series, but not positive. Sounds like the guys had the ILS tuned,
which displayed on the CDI..

(armchair speculatio)
BUT had the waypoints entered manually in the GPS and then used the
flashing waypoint light in the PIC's scan to indicate when to step down
(cheating essentially...).. they'd prolly done it many times before
(without a PT).. and this time nobody bothered to look down onto the
center console and VERIFY which waypoint it was annunciating (let alone
fly the approach solely as published using LOC/NAV and DME indications)

The profile seems to indicate they flew the approach with descents one
waypoint out of sequence.. With the database being out of date, it
should not have permitted real GPS approach modes (including a GPS
overlay of the Loc/Vor approach.. so the crew had to have manually
entered the points on their flight plan.