Autopilot does not reach cruise on derated climb

[scandinavian13 5,192]

Are you online when this occurs?

 

FSInn has a faulty weather injection problem where temp increases with altitude.  This can result in very unrealistic conditions, which result in what you're seeing.  Make sure to disable FSInn weather entirely.

 

I think Opus used to do this (or similar) at one point.  I don't think the current version has this issue, so make sure you're running the latest version of Opus, if you use that.

[Fabo 213]

 

 

In my flight plan there are about 4 waypoints at the cruise level of FL222.

 

222?

[DAL1850 51]

 

 

In my flight plan there are about 4 waypoints at the cruise level of FL222

FL222? What does your OAT read? If you keep pressing 'B', what kind of barometric pressures are you getting? Are they stable or fluctuating?

 

Please post your flight plan so others may try it. Cropped screenshots of your FMC pages might also be helpful.

[red259 31]

Sorry was tired after last flight. I meant fl220. I do fly online,but the times I noticed this issue was in offline flying. I do use opus and think I have the latest version but I will check again. I do have sp1.

I will try the flight again later today and monitor the oat and try to take some screenshots and post my flight plan. In terms of baro setting, I set it before takeoff and once I pass through Fl180 I click standard which I think is 2992. Is this the proper procedure?

[scandinavian13 5,192]

 

 

I am not programming the required temp into the FMC as I don't have topcat. Could this lack of info be causing the issue?

 

It's not a required temp.

 

On that page, you may:

1. Leave it blank (full rated thrust takeoff)
2. Enter an assumed temperature to use the Assumed Temp Method (ATM)
3. Select a derated thrust option; or
4. A combination of 2 or 3

From the sounds of it, it seems like you aren't correctly setting your cruise altitude, either on the MCP or the FMC.  Both of those need to have the information in order to recognize that you've reached cruise.

[red259 31]

I would also add that I am right on the verge of going over speed, so that may play some part in it? I tried lowering my speed to .78 but it didn't make a difference. According to my altimeter I'm flying level at 22000.

I would also add that I am right on the verge of going over speed, so that may play some part in it? I tried lowering my speed to .78 but it didn't make a difference. According to my altimeter I'm flying level at 22000.

[scandinavian13 5,192]

 

 

I would also add that I am right on the verge of going over speed, so that may play some part in it? I tried lowering my speed to .78 but it didn't make a difference.

 

Probably not.  It may be related, but not a cause.

 

 

 

According to my altimeter I'm flying level at 22000.

 

Right.  Again, the aircraft needs to know what your cruise altitude is going to be.  This is set on the PERF INIT page, and should also be matched by the altitude window of the MCP.  If either one of those is not set properly, it can cause issues.

[Bob Scott 7,720]

Last time I saw something like this, the problem was the user had loaded the acft with weight units set in KG instead of Lbs, and the jet was massively overweight.

 

Edit: if your speeds are way high, check the outside air temp--if it's crazy high (as can happen with a misbehaving wx add-on program) that would explain both the high indicated airspeed and the inability to reach cruise, as the computed climb power setting would be far too low.  At FL220 standard OAT would be ~ -29 deg C.

 

Cheers

[red259 31]

 

Right.  Again, the aircraft needs to know what your cruise altitude is going to be.  This is set on the PERF INIT page, and should also be matched by the altitude window of the MCP.  If either one of those is not set properly, it can cause issues.

 

Yep they are both definitely set and match up.  

Last time I saw something like this, the problem was the user had loaded the acft with weight units set in KG instead of Lbs, and the jet was massively overweight.

 

Edit: if your speeds are way high, check the outside air temp--if it's crazy high (as can happen with a misbehaving wx add-on program) that would explain both the high indicated airspeed and the inability to reach cruise, as the computed climb power setting would be far too low.  At FL220 standard OAT would be ~ -29 deg C.

 

Cheers

Thanks for the headsup on what the OAT should be. I did notice on one flight a sudden burst of overspeed. Like it just jumped up suddenly. I will definitely keep an eye on it this next flight. The issue of weight is interesting. I didn't change the units, but I do have the default amount of fuel on board. Normally I use only the specific amount of fuel that I need based on pfpx calculations, but since I have been doing these last couple of flights to test vas usage and try to reduce it I have just been going with whatever is in the tank. For my next flight I will use a specific fuel calculation. 

 

Chris

[Spin737 102]

Pics are worth a million posts.

[red259 31]

Just did a flight with 1/3 fuel and it went to cruise at fl220 without a problem everything else is the same way I always do it, so I think it has something to do with the default fuel weight. Was a TO2 and climb 2. I set my cost index lower this flight, so that was the other difference now at .75 vs .81. 

[red259 31]

http://i1330.photobucket.com/albums/w568/chris247482/2013-11-15_16-44-32-943_zpse3f1769d.png

 

This is my first attempt at linking a photo. I had the same issue with the 777 popup that I had with my 737ngx, so I think I may be skipping a step somewhere. In this case cruise was at FL330. I did TO2 & Climb 2. The climb went fine and it switched from climb 2 to regular climb. The plane leveled out at FL330 (on the map I passed the TOC marker) and stayed stable there for several waypoints. However, the plane stayed in climb mode during the cruise. At TOD the plane then shifted into CRZ mode and began its decent. Alt is set to FL 330 on MCP and in FMC. Altimeter was set before TO and then switched to standard at transition altitude fl 180.   

 

Chris

Here are some other screen shots with closeups in case anyone sees something I am forgetting to set. 

 

http://i1330.photobucket.com/albums/w568/chris247482/2013-11-15_16-46-19-525_zpsf6872a82.png

 

http://i1330.photobucket.com/albums/w568/chris247482/2013-11-15_16-45-1-903_zps302d603f.png

 

http://i1330.photobucket.com/albums/w568/chris247482/2013-11-15_16-45-47-495_zpsa7f7a156.png

[DAL1850 51]

Really need closeups of your FMC pages, especially the PERF INIT page along with VNAV and RTE LEGS.

[red259 31]

Really need closeups of your FMC pages, especially the PERF INIT page along with VNAV and RTE LEGS.

Yes, sorry it was my first time taking screen shots. The route page is kinda blurry in the photo but the alt is FL330 for all waypoints showing there (shot was taken before I entered my arrival star info) the waypoints on the screen are ATHOS ALB LAMED PLB. On the vnav page I confirmed it read crz alt FL330 as well. 

 

I don't have my perf intit page captured in a photo, but from my FP I know I entered a ZFW of 409.5. And release fuel of 24,215. 

[Fabo 213]

 

 

This is my first attempt at linking a photo. I had the same issue with the 777 popup that I had with my 737ngx, so I think I may be skipping a step somewhere. In this case cruise was at FL330. I did TO2 & Climb 2. The climb went fine and it switched from climb 2 to regular climb. The plane leveled out at FL330 (on the map I passed the TOC marker) and stayed stable there for several waypoints. However, the plane stayed in climb mode during the cruise. At TOD the plane then shifted into CRZ mode and began its decent. Alt is set to FL 330 on MCP and in FMC. Altimeter was set before TO and then switched to standard at transition altitude fl 180.   

 

This might very well be normal behaviour on the 777, it has a customer option to use CLB or CRZ after reaching TOC.

 

Pics are worth a million posts.

 

We need FOQA module, I tell you.