The test review will show that the management made bad decisions ignoring warnings and minor and it is going to hurt them and some heads will roll. Just watch. Stupid is what stupid does. When these air crafts are designed for at least million cycles, they do go beyond million cycles . This catastrophic failure show infant mortality and that is serious and cannot be resolved in two weeks. It may take months and Boeing will pay a big penalty for this failure in my opinion. The short sellers of Boeing will have a field day..
Mil Spec specifies -60F I am sure. All these aircrafts can be taken over by the US military for troop movement in extreme needs, in case of War, and will be designed to Mil standards and I am sure Boeing did test this -60F to
--------------- Google MIL-STD-810 pdf and read..
3. Cold and Severe Cold Climatic Categories. These areas include northern North America, Greenland, northern Asia, and Tibet. In the Cold Climatic Category, the temperature during the coldest month in a normal year may be colder than the Basic Climatic Category cold extreme of -32°C (-25°F). In the Severe Cold areas, the temperature during the coldest month in a normal year may be colder than the Cold Climatic Category extreme of -46°C (-50°F). Temperatures colder than -51°C (-60°F) occur no more than 20 percent of the hours in the coldest month of the coldest part of the area (northern Siberia) where temperatures as low as -68°C (-90°F) have been recorded. Because extremely low temperatures are not controlled by a daily solar cycle, they persist for a long enough period of time to cause materiel to reach equilibrium at extremely low temperatures
Cold soak temperatures must simulate these.
1. Normal environment considerations. All combat and combat support systems should be designed for at
least the Basic Climatic Category, meaning that design temperatures will include the outdoor ambient air
temperatures range of -32°C through +43°C. See figure C-1 and table C-I.
2. Extreme environment considerations. Materiel intended to be deployed or used in extreme climates (hot,
cold, and severe cold), in areas with extreme non-thermal weather conditions (such as blowing sand and
dust), or in areas with mobility-restricting terrain conditions (such as tundra soil and heavily forested areas)
It may turn out that the batteries will have to be kept in environmentally controlled and pressurized containers. The change in altitude and pressure drop may have as much affect on them as change in temperature.