Go Around button

[mburch]

Originally Posted by dmattmul

Highlighting the GMC GMC 507 Device list shows TO/GA Input as Open/High. Not a clue if this is correct and can’t find where to see options to change it to.

If the pin was being pulled to ground by your pushbutton, you would see it there. Look for wiring issues.

[uk_figs]

Originally Posted by g3xpert

On an RNAV approach, when the TO/GA button is pressed, a discrete input on the GTN or GPS175/GNC355/GNX375 is activated which is essentially a remote switch to unsuspend the flight plan, and allow the navigator to sequence to the first leg of the missed approach procedure.

Thanks,

Justin

With the GNX375 coupled to the TruTrak Gemini (Xcruze 110) in coupled approach mode with vertical guidance, does the 375 provide vertical guidance for the missed approach procedure to the autopilot once the TOGA button is selected or just lateral guidance.
Figs

[dmattmul]

After a series of attempts I think the issue is resolved. (I'm not a fan of the AML rockers, this is the second one that stopped working to date and never used) I've seen recommendations of 5 degrees pitch up, but this does not leave much time to apply power (My throttle is right over the TOGA so pretty easy to engage) Are most applying power first then hitting TOGA or the other way around? Are most using 5 degrees? I changed mine to 3 degrees as the performance even at 3 degrees and full power is still 500 fpm. At approach speeds (70 knots for me) there is not a lot of time after TOGA is pushed to get pretty slow if power is not in. (At 5 degrees)

[BobTurner]

Originally Posted by dmattmul

I changed mine to 3 degrees as the performance even at 3 degrees and full power is still 500 fpm. )

What is the climb gradient? I know in flat FL there’s nothing to hit, but visit the west, you’ll find many missed approach procedures that require a higher than standard climb gradient.

[dmattmul]

This seems to be a published climb gradient I could find which works out to 3.79 degrees. It would be nice to have some sort of timed departure pitch up where you can select X secs to obtain Y pitch up. I am a little sensitive to the TOGA button as a good friend (fairly new IFR pilot) of my father with 3 passengers tried to use it at night and a stall spin ensued killing all on board. I will practice more with TOGA and see if the pitch up can be changed as needed during climb out.

[BobTurner]

200’/nm is the ‘standard’ climb gradient on missed approaches. If 200’/nm or less assures terrain clearance, it won’t be published on the MAP chart. The MAP for our local airport requires 385’/nm. Add in a tailwind and a heavily loaded 172 can’t meet that.
Curious about the accident you mentioned. I use a TrioPro autopilot, and it will command nose down if approaching a stall. I thought all autopilots did that.

[dmattmul]

Bob, thanks for the input and your contributions to this forum. The accident occurred probably over 25 years ago. We don’t talk about it much in the family. My father would sometimes fly the aircraft and he told me he warned the pilot about this. He’s over 90 now and to old to ask. My father was a military pilot with over 15,000 hours and a graduate of the Navy and Air Force TPS so his civilian friends would come to him for help. The accident did create a large settlement as I recall. I’ll see what mine does at altitude if I hold off on inputting the power. The 14 has great stall characteristics.

[dstates]

Originally Posted by dmattmul

I've seen recommendations of 5 degrees pitch up, but this does not leave much time to apply power (My throttle is right over the TOGA so pretty easy to engage) Are most applying power first then hitting TOGA or the other way around? )

I recommend always power first. On a go around you need to get away from the ground. Power is what will do that for you. The auto-pilot should be off at that point and you should be able to do the pitch up with power yourself. Once you have that started then do other things like GPS and auto-pilot (Go Around switch) and retracting flaps when appropriate.

Fly the plane first. Don't rely on the plane to fly you.

[Walt]

Garmin AP has upper and lower airspeed limits to avoid stalls/overspeed when engaged.
I never fly an approach at 70k, I like 85-90 with 20deg flap.
For me TOGA then throttle, pitch then power, engine spools up quick.
At 70K you're really low on energy.