Flight Manual - Limitations Section:
The image below is from the B3 2B1 FLM. AS350 machines all have the same ISA+35 limitation.
Things to remember:
ISA+35 limited to +50'c does not mean 50'c is the maximum at any altitude or situation. It will only apply at MSL where ISA is 15'c plus the +35 = 50'c. Any climb in altitude will reduce the maximum temperature by 2'c per 1000ft. We've included some simple examples below and a graph to show the maximum temperature at each Pressure Altitude.
What is your Pressure Altitude?
To check your P.Alt, dial your Altimeter to read 1013mb and read off the altitude shown.
ISA +35 Simplified Limitations Chart
In the image above:
OAT is 38'c , 3000ft P.Alt.
ISA +35 = 44'c ..
Another 6'c increase and flight will not be permitted.
ISA+35 is just the maximum temperature limitation. There will also be a weight limitations to take into account. Be cautious when operating in high temps. If in doubt, do the calculations.