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WestAir

Cargo Cabins set to "Broil"

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All the pets stored in the checked baggage compartments are dead, because I've had the Aft and BULK cargo cabins chilled to a comfortable +40 Celsius / +100 Fahrenheit.

 

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Any clues on why I'm roasting my cargo alive? From what I can gather, the MASTER on the air conditioning unit is set to 23 Celsius / 74 Fahrenheit. The PAX cabins are all holding 23C/74F, but the undercarriage is roasting in the heat of Dubai.

 

The PACKS and TRIM AIR should be enough to get the temps down, right?

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From what I can gather, the MASTER on the air conditioning unit is set to 23 Celsius / 74 Fahrenheit. The PAX cabins are all holding 23C/74F, but the undercarriage is roasting in the heat of Dubai.
 
The PACKS and TRIM AIR should be enough to get the temps down, right?

 

The controls for the cargo temp are up on the overhead maintenance panel according to the manual.  Have a look up there (not shown in your screenshot).

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The controls for the cargo temp are up on the overhead maintenance panel according to the manual.  Have a look up there (not shown in your screenshot).

 

They were on "LOW" - set the selectors to high and the temps appear to be descending through the high 80's, hopefully towards 74F now.

 

I'm guessing the latent heat in Dubai was too much for an air conditioning setting of "LOW".

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Cargo compartments are not air conditioned, they are only heated. You can set the relevant selectors on the upper (maintenance) panel to LOW or HIGH, This sets a target temperature of 7 and 21 deg C. The heater turns on when the temperature drops 3 deg C below these targets and turns off when 3 deg C above.

 

This means that the only way for temperatures to decrease in these compartments is when the outside temperature is lower than the selected target. On a hot day with over 30 deg C ground temperature it is not unusual that cargo compartments may reach up to 40 deg C when you are on the ground. When you start climbing to higher altitudes and outside temperature drops cargo compartments temperatures will start dropping as well.

 

Note however that this drop is very slow. We have specifically asked the 777 pilots in our Technical Advisors Team to record changes in cargo compartments temperatures during their flights when we modeled this part. It may take hours for the target of 7 deg C to be reached.

 

Some passenger aircraft optionally provide air conditioning control for the forward cargo compartment through an extra selector on the overhead panel (we have not modeled this option).

Also, the freighter has air conditioning control for the fwd cargo and provides both A/C and heating for the aft cargo (modeled).

 

Finally, I assure you that your pets and livestock are absolutely safe at 100 deg F (38 deg C). In Greece where I leave, most of the days this summer temperature was between 34 and  40 deg C and my dog and cat are still alive and in perfect health :-)

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Michael,

 

I had no idea the cargo area was passively cooled with only a heater to control temps. That explains the steamy-hot temperatures I'm reading.

 

Was all of this in the manual I didn't read? :P

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I wonder whether we could get a RAAS Pets and Passengers add-on someday?

 

"Captain, everyone from row 15 back is complaining about the heat, and one old lady has passed out and is now on oxygen...."

 

Etc.

 

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Michael,

 

I had no idea the cargo area was passively cooled with only a heater to control temps. That explains the steamy-hot temperatures I'm reading.

 

Was all of this in the manual I didn't read? :P

 

FCOM Vol.2 page 2.20.7

But this is a 1300 page document, so I won't complain :-)

I only insist on reading the introduction document at least.

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