737 Not Climbing

[costamesa 88]

Hello,

Obviously I am missing something. I am on my way to EDDH from LEBL,

Route is "OKABI UN861 FISTO UY156 ADABI UN858 TABOV UM163 CTL UZ706 NVO UM170 BASUM Z78 WSN T903 RIBSO".

Gross weight is 64100. ZFW 57300.

Weather at departure "LEBL 141030Z 07006KT 020V150 9999 FEW015 SCT023 BKN030 23/19 Q1028 NOSIG" at destination "EDDH 141020Z 24012KT 220V290 7000 BKN007 16/15 Q1023 NOSIG" (loaded to AS16 in manual weather mode)

Problem is that the aircraft is not climbing after FL 330 in LNAV/VNAV/CMD. Not happening for the first time. If I try to climb with V/S I am losing speed, level change mode is working ok,

[JRBarrett 3,070]

The clue is found on your MFD, right above the engine N1 gauges. It appears to show that your TAT air temperature is +45C, which is WAY too warm for FL330.

 

You mentioned you were using AS16. That would probably be the source of the high outside air temperature. Perhaps some corrupted data in their weather feed...

[costamesa 88]

9 minutes ago, JRBarrett said:

The clue is found on your MFD, right above the engine N1 gauges. It appears to show that your TAT air temperature is +45C, which is WAY too warm for FL330.

 

You mentioned you were using AS16. That would probably be the source of the high outside air temperature. Perhaps some corrupted data in their weather feed...

Thank you very much. 

Yes I am using AS16. I loaded the custom weather that the VA provided me with in my flight plan. The active waypoint in the second image OKABI and in AS16 flight plan the entries are>

OKABI: (Calculated flying altitude 38000 feet)
- ETA in 27 minute(s) 9 second(s)
- Expected weather conditions: OKABI 130441Z 01203KT 9999 14/06 Q1027 RMK ADVANCED INTERPOLATION RMK BASED ON FORECAST GRID DATA
- Expected winds: 276/1
- Expected temperature: 19.26 celsius

So this is not something I do wrong?

[JRBarrett 3,070]

2 hours ago, costamesa said:

Thank you very much. 

Yes I am using AS16. I loaded the custom weather that the VA provided me with in my flight plan. The active waypoint in the second image OKABI and in AS16 flight plan the entries are>

OKABI: (Calculated flying altitude 38000 feet)
- ETA in 27 minute(s) 9 second(s)
- Expected weather conditions: OKABI 130441Z 01203KT 9999 14/06 Q1027 RMK ADVANCED INTERPOLATION RMK BASED ON FORECAST GRID DATA
- Expected winds: 276/1
- Expected temperature: 19.26 celsius

So this is not something I do wrong?

I don’t think you are doing anything wrong, but there might be a problem with the custom weather file from your VA that is causing the temperature at high altitude to be too warm. A temperature of +19.26 Celsius at FL380 is much too high. It should typically be around -56C at that altitude. That explains why your aircraft can’t climb.

[scandinavian13 5,192]

4 hours ago, costamesa said:

I loaded the custom weather that the VA provided me with in my flight plan

^ There's the problem.

[costamesa 88]

Ok thank you very much guys.

[fakeflyer737 991]

Just to add to what Jim said...

 

Sometime (even with RW weather on) AS (most versions I've owned) doesn't change the temperature as you go up. I very seldom have this happen, it just requires a quick restart of AS and you'll be good!

[costamesa 88]

9 hours ago, fakeflyer737 said:

Just to add to what Jim said...

 

Sometime (even with RW weather on) AS (most versions I've owned) doesn't change the temperature as you go up. I very seldom have this happen, it just requires a quick restart of AS and you'll be good!

OK, this is good to know too. Thanks Ron.