USMCFLYR

I don't know if it is standrad either, but our revamped KA300Fs (the ones with the PL21 cockpit conversion) have dual Collins FMSs. Right now with the EFIS-10 setup we don't even have an FMS.

USMCFLYR

Avanticaptain

There are NO tricks to this. FOLLOW THE MANUAL. Approach mode uses tighter tolerances to drive the flight director and hence you or the autopilot. On non precision approaches add the VNAV and you’ll have vertical guidance rather than “dive and drive”. NEVER take anecdotal information over the manual. Be safe!

galleycafe

General advice!

Plane coffee

Gundriver64

Not necessarily. If I "follow the manual" in certain instances then I'll be busting black and white rules associated with my operating rules. Bottom line, is to know what the automation does, how to apply it, and not settle for "unanticipated happy outcomes". Also, in certain conditions dive and drive is still a valid technique and may in fact be the desired means depending on the SBAS condition(s) of the FMS, where you are globally, coupled with the type/design of approach.

EMAW

The Collins guidance issued by flight safety for the KingAir 350 (although it doesn’t specify type) says: MDA use NAV, DA use approach.

Gundriver64

This^^^^^^^

USMCFLYR

That is what my book says.

Red Forman

I’ve been flying PL21 for 10 years and have never read, heard, or been taught to always use approach mode for all approaches.

P180 Jockey

Hey, guys and gals- New here, but I do have a question on this:

I agree that the proper procedure is the procedure recommended by the manufacturer. However, in a non-precision approach, using Nav/VNAV to the MDA creates a couple other workload issues:

1) You're gonna have the MDA altitude set in the window and will need to start twisting for the MA altitude at the highest workload phase of the flight (though I agree this is not a huge issue if you "just fly the airplane" on the miss and conduct a SNAP checklist).

2) In A/P mode, the plane is gonna level and stall if you don't have your head out of your butt at MDA, in any case.

So, whether you're flying in Appr/VNAV, Nav/VNAV or Nav/Pitch (dive and drive), you're gonna have to know the MDA and when you're approaching it. That done, it just seems to me, there's two alternatives:

NAV Mode:
Go missed, power up, clean up, SNAP

APPR/VNAV Mode:
Go missed, power up, clean up, SNAP (with the "A" part already set for you, greater precision on the Approach Profile and a single Manual of Arms from Approach to Approach)

What am I missing here? Input welcome.

USMCFLYR

Does it?

Can you provide a reference for it?

In our old AP, it did have tighter tolerances for the AP, but if the PL21 manual reads to use NAV mode for non-precision approaches (like a VOR/DME SIAP for example), then if APPR mode did give greater precision on this approach why would they dictate NAV mode?