Hi,

 

Today I tried to make it from PANC to PADU (Unalaska, Dutch Harbour) using real world weather from AS2012! So there I was on the GPS E and weather was down to 600 and 3 miles in snow. Obviously I did not make it in so I diverted to Cold Bay. Pretty cool and very challenging. This was my first go around and real missed approach in the NGX and I botched my way through it.

 

I had a few problems.

 

1. The GPS E was not in the database so I built it myself but there was a problem when the aircraft got to the MAWP (missed approach waypoint) it turned on its own just before it to the MAHP (hold point). Obviously it did this because that was the next fix. My question is this, how do you either build an approach like the way it is in the approach database where after the MAWP or RWY the pink line goes to a dashed blue line (presumable this means I have to "activate" the missed when starting the missed?) so the aircraft does not turn until I tell it to. The other way would be to just insert a disco between the MAWP and the next fix or MAHP on the missed right. How do I insert a disco w/o deleting the next fix. I suppose I could delete the next fix and then re-enter it past the disco but I would rather learn how to program that blue dashed line. Does it have something to do with inserting those 2 waypoints past the MAP? I think one is an altitude and the other is a RWY #. Is there a way to do this properly or is it not necessary?

 

2. When I went missed I hit the TOGA and put it into heading mode and even though I had 3000 feet set into the altitude window the jet climbed past that to 4000 (there were no altitude constraints) and this did not make any sense. It would not even respond to alt hold to stop the climb past 3000 feet. I had to wait for it to level at 4000 before I could then descend back to 3000 feet. I cant think what I have done wrong here if anything.

 

Thanks

Marc,

 

1. You can't manually build an approach and have it perform the way a pre-coded one does - it's like this with the real FMC too. To get it to do what you want you'd actually have to code the approach in the PADU.txt file in FSX\PMDG\SIDSTARS using our terminal procedure syntax.

 

2. TOGA is a flight director mode only, not an AP mode. You need to select a vertical mode like LVL CHG or VNAV after the initial part of the go-around has happened. Always remember that you're still the pilot too - if the plane starts doing something you don't want, take over and stop it. The autopilot isn't infallible.

I did all that. And I know to allways watch the AP, its not like I am in the back dozing off. Anyway that does not explain why it went to 4000 when there were no constraints and 3000 was in the altitude window. And alt hold did not stop the climb.

Ryan, I think he's right about this.

A TOGA go-around should have captured the MCP altitude of 3000 feet even if another vertical mode ( LVL CHG or VS or VNAV) is not selected and the vertical mode remained in TOGA. ALT ACQ should have engaged as the airplane approached 3000 feet followed by a ALT HLD.

Of course Marc, I'm not sure what kind of appraoch you were flying, but after pushing TOGA, the autopilot disengages and the missed approach is hand flown with the FD.

If you’re flying a CMD mode ILS with both autopilots engaged, then after pushing TOGA, autopilot B would disengage and autopilot A would fly the go-around.

 

Marc, a screen shot might help.

 

 

John Floyd

About the climbing through 3000': what pitch mode did you select and what did the FMA show?

 

Bert Van Bulck

To be honest guys I am ashamed that I was surprised when the autopilot disconnected when I hit the toga. :Nerd: Anyway it was the GPS-E into Unalaska. I flew the self built approach in VNAV descent and LNAV and had the MDA set in the MCP until 300 feet below the final approach fix altitude then I put in the MAHP(hold point) altitude wich was 3000 feet. About 1 mile from the missed way point the aircraft began a turn on the missed toward an 1800 foot mountain! So I engaged heading and flew the rest of the way to the MAP. So when I pressed toga I was in heading and VNAV alt hold or path (cant remember which now) at the MDA. I will have to try it again and see. I will probably get the opportunity to try another missed approach as I am now stuck in Cold Bay waiting for the weather to get above 1800 and 3 at Unalaska Dutch Harbor. I think I can count on my hand the number of days Dutch Harbor is above 1800 and 3. Anyway, the aircraft climbed to 3000 feet and even gave out an altitude alert at 3000 for 1000 to go so I don't know what happened. I could not even stop the climb at 3200 with alt hold. But to be honest I don't remember when I re-engaged the ap again in the climb, I think It was before 3000 but that should not matter anyway since the altitude 1000 to go alerter went off at 3000 so it was like 4000 was in there but it was not. The other wierd thing is I got a TCAS RA at the same time I hit TOGA telling me to descend. Talk about information overload at the worst point. There was no traffic on the TCAS either, weird.

 

I think I can figure out how to trick the FMS into inserting a discontinuity after the MAP for these hand made approaches so the aircraft flies strait all the way to the MAP and then lets the pilot decide what to do. Kind of interesting that this feature is required by the FAA on IFR approach certified GPS systems where the unit goes into OBS hold or suspend at the MAP for this very reason. I know however that I did hand build this approach so this feature can not be built in unless I edit the file. I wonder though, that blue dashed line for the missed segment in the database approaches if that is automatically activated if the aircraft is passed the MAP and the plane is still in the air? I'll have to check the operating manual again for that.

 

In the heat of the moment I may have forgot to select a pitch mode untill hitting alt hold, but it seems alt hold should have stopped the climb.