Originally Posted by deuzx
I wonder about what the 100% N1 stands for? In some cases the TOGA thrust is above this? Mech. stop for thrust leaver is about 107% ...When you buy an 20K rated engine. When does it produce 20K? At 100% N1?N1?
Within the flat-rated range of OAT, N1 varies with OAT to maintain constant rated thrust (higher temp, higher N1). This is because of the air density changing with temperature. So it's virtually never right at 100%.
Above the flat-rated OAT, N1 decreases with increasing temperature. Obviously thrust decreases in this range, but the manufacturer imposes this limit to protect the hot section parts.
When you reduce the N1 with 10% does the thrust reduces with 30%?
I don't recall just what N1-to-thrust derivative applies, but 10-to-30 seems about right.