DA40 Min Oil Temperature
There's a bit of discussion going on in my operation as to what temperature we should be letting the oil reach prior to takeoff in the DA40-CS fitted with the IO360 and Hartzell propeller.
The green range of the oil temperature gauge does not start until 149ºF, and some instructors refuse to take off until this temperature is reached (can take a very long time, especially in mid-winter), while others maintain any temperature over 100 is sufficient. The AFM doesn't mention a minimum temperature for takeoff anywhere –*just that for continuous operation temperature should be above 150, which it obviously is after a few minutes airborne.
What's the right thing to do?