Hello, just wanted to get feed backs as to how would a pilot inside a 737NG cockpit recognize and distinguish between an engine stall, surge, separation and severe damage
What would the Eng indications be like ( N1/N2 fluctuations etc) and any other physical characteristics like sounds, yaw.
A stall will blow forward, so for a second you will not only have a loss of thrust but it be the opposite. In low light you may see a fireball on the stalling engine. I have been at the nose of a 742 with JT9's advancing to high power during a stall and I could feel and see this happen.
Having said that it was quite normal on older engines with loose tolerances and simple controlls. On the modern engines it is rare but more detrimental to the motor, normally cause for it to come off wing.
When there is severe damage it can result in siesure (you will feel this and obviously see it in your instrumentation). Seperation is the worst case scenario, Drastic EGT change is th first indicator followed by eng speed reduction and fire is the largest issue.
Hope this was the simple answer you seek.