Sillypeople
Firstly you dont de-rate to leave thousands of feet behind. The longer the runway used the more de-rate you can take. Yes ? Exactly what is unsafe about meeting the performance requirements while causing the least stress to the engine ?
Maybe the entire industry is wrong and you are right ?
Secondly we are talking about engine efficiency here not airspeed. Why do you think Jet engines are more economical at high altitude ?
Last edited by 8che; 29th Nov 2012 at 10:12.