Absolute minimum temperature?
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Join Date: Jan 2007
Location: Nottingham, UK
Age: 74
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Absolute minimum temperature?
Is there a Boeing limit of absolute minimum OAT? (Not minimum fuel temp)
The lowest I personally observed was -74*C at FL450 over the Baltic, but was told by a BA F/E that he had seen -85*C over Siberia.
Is there a limit and why? Thanks.
The lowest I personally observed was -74*C at FL450 over the Baltic, but was told by a BA F/E that he had seen -85*C over Siberia.
Is there a limit and why? Thanks.
Join Date: Jul 2013
Location: Everett, WA
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Originally Posted by Intruder
For many things, they can only certify what they test to.
Another issue is many of the data tables only extend over a specific temperature and altitude range - e.g. engine ratings. I recall an issue perhaps six or seven winters ago when a big cold front hit part of Europe - it was bitter cold, but more importantly the pressure altitude dropped well below -1000 ft. The takeoff performance data for some types didn't go below -1,000 ft., resulting in several aircraft being grounded for several days.
Join Date: Apr 2005
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Most tends to be a fuel gel point, read about a DC10 over Russia years back that was reaching min tank temp. ATC wouldn't allow any deviation lower/faster etc....... the F/O suggested wing deice, the temp slowly rose due to hot bleed air in the leding edge. Several years back air canada was stuck in yzf for 2 weeks because the temps didn't rise above -48 during that time, what [email protected] makes a skidoo that doesn't run in the winter. Oh right some PQ numb nuts
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Been plenty of incidents over the years with fuel gelling. BA38 comes to mind. An aircraft which I was looking after, some years ago, nearly came to grief on the way to NZ - fortunately the PIC recognised the symptoms from a conference paper several years prior, descended, and the problem resolved.
Join Date: Oct 2019
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738-800 fuel filter bypass
Back around 2008, when flying in -64°C +/- temps for any length of time, for example, from STN to Tampere, about the time of TOD, we could expect to get a master caution and fuel filter bypass which would clear by the time we had parked on the ramp. I think there used to be a bulletin but it was removed some time ago, due to some tech mods perhaps.
Join Date: Feb 2001
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Originally Posted by HILETI
Is there a Boeing limit of absolute minimum OAT? (Not minimum fuel temp)
The lowest I personally observed was -74*C at FL450 over the Baltic, but was told by a BA F/E that he had seen -85*C over Siberia.
Is there a limit and why? Thanks.
The lowest I personally observed was -74*C at FL450 over the Baltic, but was told by a BA F/E that he had seen -85*C over Siberia.
Is there a limit and why? Thanks.
Only half a speed-brake
Join Date: Apr 2003
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Stolen shamelessly from the inter-web. Continental's 777-224, dated 08/09/02 (for whatever Christmas sake that means?).
The left edge-line is relevant, showing a binding limit at -75° C when above FL315.
On Airbuses the FCOM chart is pretty much the same.
The left edge-line is relevant, showing a binding limit at -75° C when above FL315.
On Airbuses the FCOM chart is pretty much the same.
Join Date: Oct 2019
Location: north pole
Posts: 53
no joy....yet
after looking until eyes glazed over, using 50/50, ask the audience and phone a friend, I will stick with my memory of -65C. I am sure of winter before last, several other colleagues, in same airline and same a/c requesting descent due to low temperature enroute. i think I remember our ops manual or performance manual having a chart like the above 777 environmental envelope, but I cannot find it. Yet.
I did see, the lowest temperature on the TO performance charts as -40C for -800 and -60C for -700. And oddly, the quick turnaround brake charts show -54C.
the emergency O2 chart for flight deck shows a low of -10.
I did see, the lowest temperature on the TO performance charts as -40C for -800 and -60C for -700. And oddly, the quick turnaround brake charts show -54C.
the emergency O2 chart for flight deck shows a low of -10.
Last edited by 70 Mustang; 10th Jan 2021 at 15:02.
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Originally Posted by 70 Mustang
i think I remember our ops manual or performance manual having a chart like the above 777 environmental envelope, but I cannot find it. Yet.
Only half a speed-brake
Join Date: Apr 2003
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Posts: 3,097
70 Mustang Your charts say TAT, mine OAT. Reader beware.
Check Airman It's the spirit of the date, not the format that matters. :-)
Check Airman It's the spirit of the date, not the format that matters. :-)
Join Date: Oct 2019
Location: north pole
Posts: 53
Max min i could find...
TAT -65C is the coldest i could find in any chart.
Do you have a page number or a screenshot of your chart? I cannot find it.
I only have FCOM, FCTM and the above Flight Planning and Performance Manual.
I haven’t seen an AFM for the 737-800 since 2003 at Excell Air at LGW.
Do you have a page number or a screenshot of your chart? I cannot find it.
I only have FCOM, FCTM and the above Flight Planning and Performance Manual.
I haven’t seen an AFM for the 737-800 since 2003 at Excell Air at LGW.
Last edited by 70 Mustang; 30th Dec 2020 at 19:42.
