BelArgUSA
No temperature limit on the engine intake air on Concorde.
There was however a limit on the aircraft nose temperature
TMO of +127ºC, which could easily be reached in warm air.
Couldn't understand how they'd arrived at that precise figure until one of the original design team patiently explained it to me at a reunion dinner.
The square, and square root, of the temperature came into various design equations, and so - in those pre-computer days - he said they selected +127ºC to make the mental calculations easier!
He must have seen the baffled look in my eyes.
Think Kelvin, he said!
Regards
Bellerophon