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That the prototypes 001/002 had windows approximately the same size as the 707.
However, the airline service (and I think the pre-production) models, i.e. the ones that you would have flown on, have much smaller windows, roughly the same size as my hand <brag on> tested on 08 Sep 2003, LHR-JFK BA001 <brag off> or the front cover of a paperback book.
This change was effected due to the requirements of descending in case of a window breakage from FL 58 down to a safe altitude. Smaller windows means that the air in the cabin escapes slower, and gives more time for an emergency descent to be completed. Quite a good reason, wouldn't you agree?
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