Defrost air flow

kilr4d · #1 11-06-19, 08:29 AM

Ask your A&P if he'll let a motor shop that works on DC motors take a look at it. It's becoming more common as the legacy fleet ages and parts cease to become available. If they can find an issue with a bearing/winding/shaft etc maybe he'll sign it off.

Bobcllns P337 · #2 11-06-19, 08:51 AM

Quote:

Originally Posted by kilr4d

Ask your A&P if he'll let a motor shop that works on DC motors take a look at it. It's becoming more common as the legacy fleet ages and parts cease to become available. If they can find an issue with a bearing/winding/shaft etc maybe he'll sign it off.

John, I just had the motor fixed so I believe the squirrel cage is allowing bypass since I get good airflow from it but no pressure

n86121 · #3 11-16-19, 09:52 AM

My older T337D relies on ram air pressure, so you only get good defrost in flight.

On ground, not much at all, just from front prop backwash into ducting.

The only motor is the one mounted on the heater for combustion air flow.
You 'throttle back' that back (partially close duct) in flight because adding ram air is too much.