Flight Crew Flight Instructor
Communication Breakdown; Distraction; Troubleshooting; Workload; Training / Qualification
Aircraft Equipment Problem Less Severe
Aircraft Aircraft Damaged; Flight Crew Landed in Emergency Condition; Flight Crew Inflight Shutdown; Flight Crew Returned To Departure Airport; General Maintenance Action; General Declared Emergency
Aircraft; Chart Or Publication; Procedure
While training for the Part 61 commercial multi-engine course for the student. We did a full engine shut down at 4;500 FT; 4 miles east of the airport. The engine was fully feathered for about 1 minute before we started doing the checklist to unfeather the engine and commence an air-restart. The engine did not un-feather after following the procedure in the checklist; so we changed to do the starting the engine without accumulator checklist; however on our 4th attempt to start the engine with the starter the intercom stopped working and the right engine instruments stopped working as well. After this happened we decided [to call] ATC but they could not hear us properly so we went ahead and declared an emergency; squawk 7700 and make a straight in for Runway 28L. We could not communicate with ATC properly; however we could hear them fine. We did a couple of 360 degree turns to lose altitude. Before reaching 1;000 FT and having the runway assured we decided to put the landing gear down and it did not work; so we proceeded to do the Emergency Gear Extension Checklist and we had a 3 green gear down indication. We landed the aircraft with no other issues. Later on after we cleared the runway we were met by the emergency vehicles and towed back the ramp.Better maintenance inspection on the aircraft since it is not the first occurrence on this same airplane with the same engine. Add to the checklist to remind us to reduce the electrical load and wait longer time between times we try to restart the engine; since when its happening while trying to teach the student and other thing come into play we tend to fully focus solely on what the checklist says and forget to think about the other factors. This way maybe we could have maintained our radios to have better communication with ATC and being able to lower the landing gear using normal procedures.
A PA-44 instructor and student shutdown an engine for training but were unable to unfeather it. Multiple unfeather attempts drained the battery; caused communications difficulties; required manually lowering the landing gear and landing in an emergency condition.