STec 3100 coupled approaches & missed approach

Davidl13

Pre-takeoff checklist
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Papaco
Up until today, I flew coupled approaches and disengaged the AP at the MAP or DA. (Or a bit higher ( that is all my former instructors knew how to show me)

At that point I would have hand flown the landing or missed approach with missed guidance from my garmin gtn 750 and flight director. Not terrible but it has its problems.

One problem is that the glide slope or glide path or advisory only slope, will drive you into the ground if you let it...so I would disengage AP so when I added power I could climb and not put a hole in the ground....or bust minimums...and there is a lot to do.. especially since you are taking over from servos that had certain pressures enabled...So there is always a certain amount of destabilizing/correction... I never understood why the AP wouldn’t fly the missed.. or hold the MDA... vertically.... and (not one cfii I worked with knew how to use this sophisticated equipment to its fullest, yes including very experienced cfii)... today I thought through it and figured it out).. .the answer is , you have to manually manage vertical guidance by leaving glide slope mode after it is captured. (One nuance to know is that if in VS mode prior to glide slope capture, you can still have glide slope capture engage, so make sure to switch to VS, AFTER, GS was already captured.

you can switch vertical guidance on the AP (from GS) to VS with Alt preselect at the MDA or Alt hold (and use the down arrow @ 20’ per click) , then setup the altitude preselect to the missed altitude, so that when you get to the MAP and go missed.. add power and click follow missed (on the gtn) and VS (on the AP) and you have a fully couple approach and your AP will fly the published missed... and you can be looking for a runway and/or not worrying about altitude and heading while hand flying... and taking care of a pile of business at that moment.

This is an amazing game changer.. wow... much better.. less stress, more ability to manage the parameters you need to, while flying the exact correct route/alt..... the AP managing everything except my power, cleanup, butonology and communication...big big deal...I learned a lot today.. maybe everyone else already knows this, but for me it was a biggie

Ps.. peanut gallery... yes I will keep my hand flying skills... and continue to practice hand flown approaches too

Shout out to STec... give free seminars/videos on how to use your autopilots to their fullest, there are many instructors who have no clue... none... I bet you will sell more of them..
 
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You can also use the TOGA button at DA or MAP. Most missed approach procedures have you fly runway heading for a bit. The TOGA button will keep you level and pitch you up to approx Vy. Push your power up before the TOGA button so you don't run out of airspeed and get that annoying alert. This mode will immediately get you on runway heading in a nice climb.
Then you have time to unsuspend (430/530) or follow missed (GTN). Then push NAV to get you on the missed procedure course and IAS to maintain the climb at the speed you want. Don't forget the gear and flaps; the 3100 won't help you with those.
Once the approach is armed, I set the altitude preselect at the missed hold altitude.
The 3100 is a great autopilot. I'm not sure a CFII should be expected to know all the features of the new breed of digital autopilots unless they hold out that they do.
 
Up until today, I flew coupled approaches and disengaged the AP at the MAP or DA. (Or a bit higher ( that is all my former instructors knew how to show me)

At that point I would have hand flown the landing or missed approach with missed guidance from my garmin gtn 750 and flight director. Not terrible but it has its problems.

One problem is that the glide slope or glide path or advisory only slope, will drive you into the ground if you let it...so I would disengage AP so when I added power I could climb and not put a hole in the ground....or bust minimums...and there is a lot to do.. especially since you are taking over from servos that had certain pressures enabled...So there is always a certain amount of destabilizing/correction... I never understood why the AP wouldn’t fly the missed.. or hold the MDA... vertically.... and (not one cfii I worked with knew how to use this sophisticated equipment to its fullest, yes including very experienced cfii)... today I thought through it and figured it out).. .the answer is , you have to manually manage vertical guidance by leaving glide slope mode after it is captured. (One nuance to know is that if in VS mode prior to glide slope capture, you can still have glide slope capture engage, so make sure to switch to VS, AFTER, GS was already captured.

you can switch vertical guidance on the AP (from GS) to VS with Alt preselect at the MDA or Alt hold (and use the down arrow @ 20’ per click) , then setup the altitude preselect to the missed altitude, so that when you get to the MAP and go missed.. add power and click follow missed (on the gtn) and VS (on the AP) and you have a fully couple approach and your AP will fly the published missed... and you can be looking for a runway and/or not worrying about altitude and heading while hand flying... and taking care of a pile of business at that moment.

This is an amazing game changer.. wow... much better.. less stress, more ability to manage the parameters you need to, while flying the exact correct route/alt..... the AP managing everything except my power, cleanup, butonology and communication...big big deal...I learned a lot today.. maybe everyone else already knows this, but for me it was a biggie

Ps.. peanut gallery... yes I will keep my hand flying skills... and continue to practice hand flown approaches too

Shout out to STec... give free seminars/videos on how to use your autopilots to their fullest, there are many instructors who have no clue... none... I bet you will sell more of them..

You should write S-Tec and ask them why they don’t publish this procedure.
 
You should write S-Tec and ask them why they don’t publish this procedure.
It's so they have room to describe how to use it for a Back Course Localizer approach. :confused:
 
Day 3 of practicing coupled approach and missed on non precision, with the goal of staying coupled the entire time.

-Capture GPSA at FAF and fly it down to MDA or DA
-after GPSA capture, Change alt preselect on g500txi to “go missed altitude”

- For MDA press Alt Hold 100’ above the MDA (this will have you settle on or 20’ above the MDA (use down arrow for 20’/click)

-At DA or MAP (on MDA) press VS on STec, add power, press “go missed” on gtn750 at MAP

(Even though VS is set to -1000, as long as the altitude preselect is set to an altitude above the current altitude (the missed altitude), then the VS button will climb at a default of +500fpm, use up arrow on STec to increase that value at 100fpm per click if you wish

This procedure results in a fully coupled approach and missed procedure.

thisnisnthe simplest and most stable, never decoupling from the glide slope or advisory path
 
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