Flight Directors

[Orvilleflyer]

I agree with Brian. If it's broken, write it up.

 

[DC9stick]

On our DC9's, antique steam powered, (FD109) FD use is pretty much Capt. discretion.
The MD-80 on the other hand is a highly automated aircraft with two autopilots and FD use is mandatory during all phases of flight.
All training is also done with the FD engaged.