|Quoting WAH64D (Reply 262):|
It can't be done indoors. The cold soak test requires that the aircraft is left to sit in real world conditions for a prolonged period with a temperature of -30 degrees C or less. It must then be able to start engines normally, taxi and takeoff without any cold induced anomalies. There is only one place in the world that this can be done without constructing a purpose made strip and that is the arctic circle.
I posted this a few minutes ago, but just when I thought a.net was working the post disappeared.
Your -30 might have come from something like this WAH:
"MSN004, the second A380 to fly aircraft, spent five days in conditions of up to minus 30 degrees Celsius to prove full functionality of the systems under extreme weather conditions. Such trials included powering up the aircraft, the engines and hydraulic systems after a full 12-hour period at such low temperatures. The batteries were taken away overnight and kept in a warm area. The next morning, batteries were reinstalled onboard the aircraft for the tests. On the way back from Iqaluit, the A380 also carried out polar navigation tests."
I suppose "up to" actually means down to, so maybe -25 would have been the required temp, but they got down to -30. Their PR
folk should read a book on clarity of expression!
Even for areas well inside the Arctic circle, reliable and continuous temps of minus 25 or lower are not found before January - so it appears.
And yes, the S Hemi does have winter in June-July, but those sorts of temps - apart from the high Andes or the top of Mt Cook only occur reliably in the Antarctic itself. And having decided to cut loose from Antarctica in the late Cretaceous, S Amer, S Africa, Aus and NZ
had drifted sufficiently far N by the early Eocene (the zone of Nothofagidites asperus if you want to be picky) to allow the circum-Antarctic current to circulate and this moderates the winds coming off the polar ice-cap (thank heavens!!). It is just how the S Hemisphere works!!
Specifically the 787 will be quite a bit different to earlier planes in relation to electrical systems having replaced much of the hydraulics. The batteries are taken out and kept warm, but the rest of the electrical system has to be able to withstand the cold soak. Presumably these systems will be very new and might well require more testing than systems developed more from ones in current use.