PDA

View Full Version : 787


Hasan_787
19th Dec 2015, 19:27
Hi,

I am under training for the 787 and I have a question I hope someone could answer it for me.
With LIQUID COOLING R, one of the steps in the checklist is not to exceed 260 knots when the airplane is below 6000 feet. Anyone knows why?. I couldn't think of anything. Thank.

Fly3
20th Dec 2015, 02:09
They decided that dynamic heating due to airspeed might cause over loading of the remaining PEC if the airspeed got to high.

Cough
20th Dec 2015, 10:38
Curiously, the same statement is also on the Pack L+R checklist...

Hasan_787
20th Dec 2015, 11:05
Cough, you are absolutely correct and the weird thing there also is, when you are descending as the checklist for PACK L+R tells you to, notice that it says you descend on Vmo/Mmo. Now, if I do that, by the time I reach 10000 I'd be more than 260 Kts for sure!!!! :confused:

FLX/MCT
20th Dec 2015, 11:46
As someone not current on the type at all could you guys please specify what the liquid cooling does? I am really curious.

HPbleed
20th Dec 2015, 12:28
Does what it says on the tin? It's cooling, in liquid form. For the electronics. So many electrical systems etc that air cooling via fans isn't efficient enough.

Amadis of Gaul
21st Dec 2015, 13:59
Does it use Prestone®?

Manual Reversion
21st Dec 2015, 14:41
60% polypropylene glycol 40% deionised water...so it says!

Amadis of Gaul
21st Dec 2015, 15:20
Sounds more like Havoline then.