Cold soak under 737 wing?

[Bearcat]

an f/o asked me the other day why is the under- neath starboard wing always more cold soaked with ice deposits than the port side. To be honest I never noticed this and if it aint in the Boeing manual I dont get to excited but I said I know a place where i have got answers before so is this a christmas teaser or a load of john bull?

[Flight Detent]

Hi all,
Apart from the refueling panel, there is absolutely so difference, system-wise between the two sides. Have you considered on which side the sun rises??

Cheers:E

Errr.............that should read "no difference".......ta!

[SPEEDBIRD5FP]

i MAY BE REALLY SAD 4 KNOWING THIS, BUT THE NO.1 TANK HAS THE FUEL TEMP MONITOR, WHY??? IT HAS THE COLDEST FUEL.
THE A SYSTEM HEAT EXCHANGER IS IN THE LEFT TANK AND THE B SYSTEM SYSTEM IS IN THE RIGHT TANK. THE A SYSTEM HAS A SMALLER HEAT EXCHANGER, SO LESS HEAT ABSORBED BY THE FUEL, THEREFORE COLDER FUEL.
HEY PRESTO!!!

[Bearcat]

Speed bird....your a genius. Merry Chrimbo.

Bearcat

[Flight Detent]

Hi all,
May I say one more time, there is no equipment differences between the two sides, other than the refuel panel and the temp probe.
The temp probe is traditionally in the LHS (INBD) fuel tank of Boeing airplanes!
The hydraulic system A & B heat exchangers are the same, but, of course, the heat load imparted to them can/will be different.

Cheers:hmm:

[POOKEY]

Flight D, I think Speedy is correct on that one especially when you are talking about the classic, I seem to recall this one somewhere else...Cheers big ears

[B73567AMT]

Don't think so Pookey, unless Speed is referring to the B737-100/200s (I really am not sure about the Heat Exchangers on those Aircraft), he is incorrect.

The 737-Classics have identical Heat Exchangers in the left & right wing tanks.

The Left Main tank is not "traditionally" used for fuel temp readings.

The 737s which have an equal amt of exchangers for both tanks use the left. The B757 which uses 3 ht exh (2 in lt tank) use the reading from the right tank (coldest tank). The B767 and B777 are opposite of the 757 and use the temp from the coldest tank, in this case being the left tanks.

[av8boy]

Standard Disclaimer: The only thing I know about 73s is, um... OK. I know nothing about 73s...

However, as I do whenever I have a 737 systems question, I consulted http://www.b737.org.uk/index.htm which told me:

Fuel temp is taken from main tank 1 because this will be the coldest as it has less heating from the smaller hydraulic system A.

Thoughts?

Dave

[B73567AMT]

The statement regarding the "smaller System A" doesn't mean that the Heat Exchanger is smaller, because it is not. System "A" has less fluid than the System"B" side. "B" holds 4.8 US gallons and "A" holds 7.2 US gallons of fluid.

System "A" pumps both electrical and engine driven are indentical and provide the same outpiuts. "B" system has bot more runing off of it, hence the larger reservoir. So maybe the fluid on the "D" side with the extra work gets a little hotter.