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View Full Version : NG 737 LNAV vs VOR/LOC


Boeinguy
28th Sep 2004, 14:44
I don't like the way vor/loc captures the localizer in new generation 737's. It seem rather abrupt and aggressive compared to the classic 737. Additionally, it sometimes flies through the localizer and on long fimals, it seems to 'hunt' the wide localizer course.

I prefer to capture using LNAV and if I'm on a long final, to leave it in LNAV until 20 miles from the runway or so. Anyone have similiar experience with this?

B737NG
30th Sep 2004, 04:14
You should bear in mind that the LOC is accurate for up to 18 NM
only and the GS in some cases only 10 NM. So if you stay in LNAV
and then change to VOR/LOC or APP closer then 18 NM you will
have a more accurate track guidance and the AP is not chasing
the beam signal to full deflection on both sides. If he still does it
close the Avionics are not accurate enough and mainenance has
to look after the Bird. Remember the NG uses GPS for position
update and is more accurate then the B737-300 to 500.

NG