Monkey Doing Girl Monkey

[Jmmccutc]

what determines the critical engine in a multi? i was at work and there was a guy saying how he was just going to overhaul both engines because the critical one will be due up shortly anyway...

i was just confused as to what determines this...and why he needed to do both if the times are different...

 

[crowbar]

Lay off the monkey sh!t, put HOT BLOND CHICK or something.

 

[Pilot124]

It's the engine with the most adverse effect on controllability and climb performance of a multi-engine airplane if one were to fail. In other words its left engine. The larger moment arm (just like p-factor in a single)of the right engine's descending blade produces more thrust and its arm (moment) is farther away from the the longitudinal axis producing extreme left turning tendencies. If the critical engine (left)is running ok and the right engine goes down the left turning tendencies would be less because the descending blabe on the left engine has a shorter arm to the longitudinal axis thus producing less left turning tendencies.

 

[Jmmccutc]

that makes sense...so if you have a twin with counter rotating props, there is in ecence no "critical" engine at that point?

 

[LAXSaabdude]

that makes sense...so if you have a twin with counter rotating props, there is in ecence no "critical" engine at that point?

That is correct. Cessna Crusader, Piper Seneca, Seminole, and Navajo CR/Chieftain have no critical engine. Some Garrett powered turboprops have props that spin the wrong way, so the right engine is the critical.

LAXSaabdude.