Dear all,

 

For my project of the University of Amsterdam for Applied Science, we've to do a project about Flight Planning & Operations with a malfunction about the following:

 

Chiller Boost Fan u/s

ATA: 21-26-02

 

There's alot to find on the internet, but cannot figure out what's the 'Chiller Boost Fan u/s'. Thus this came for me with the following questions:

- What is the 'Chiller Boost Fan u/s' of the B777(-300);

- If anybody had the ATA 21 for me, are you able to send me a PM about it?

 

Kind regards,

Steven

Air chillers supply cold air to the galleys for refrigeration, in the forward and middle galleys these are mounted in the ceiling (aft galley units are mounted in the lower lobe). The exhaust for these chillers is ducted to the mix bay where the mix manifold is located. This duct contains the chiller boost fan which aids the flow of the exhaust air toward the mix bay. There are also holes in this duct that vent the hot air into the cabin ceiling area when the fan isn’t operating. The chiller boost fan operates automatically and only when the following conditions are met:

1. The airplane is on the ground (the fan turns off when airborne).
   
2. At least one pack is on.
   
3. TAT is higher than 7c.
   
4. The forward cargo fire switch isn’t armed.
   

I hope that helps a bit.

 

Brian

That is a good explanation about what the chiller boost fan is. Now if we had the "u/s" at the end of the sentence, simply means that the chiller boost fan is unusable or is not working for some reason.

 

The ATA 21-26-02 is the section of the approved manual that allows the airplane to continue flight operations with this particular equipment inoperative under certain circumstances.

 

As the chiller boost fan is not relevant or important for safe flight operations basically the ATA 21-26-02 tells you that the airplane may continue to flight for up to 10 days before repair or replacement is made to rectify the problem. This particular item does not affect dispatch, performance or impose any restrictions or specific operational procedures.

 

 

Oh great information. I'll forward this usefull information to my project group and we can use it very well. Brian and Cristian, your information is really appreciated and many thanks for that =)

It is not the ATA Chapter that tell's you for a safe ops of the aircraft, therefore we use the so called MEL wich is the minimum equipment list.

The MEL tells you if you are still on the safe side or not and every operator has it's own. The manufacturer gives you the MMEL, the master

minimum equipment list and you as the operator can change some requirements but they can't be less strict.

But that's just for info...

 

Greetings,

Sven Wendel