ZMP controller described an unauthorized restricted airspace entry when an IFR aircraft failed to re...

Narrative:

Cessna 208 departed pln and was flying the usual route. When the aircraft was just north of glr; I noticed he was very slightly left of course and needed to be turned for military airspace. The r-side tried numerous times broadcasting [to] cessna 208; 'turn 15 degrees right;' with no reply. Cessna 208 was on a good frequency and should not have had issues hearing the call. Cessna 208 penetrated the restricted airspace and shortly after we lost his transponder. We tried to relay through another aircraft to reach the cessna 208. We got him back on frequency a few minutes later. He responded that he had an issue with his radio and lost his transponder and that he smelled something burning. He was turned out of the airspace and identified on a primary target with no further incidences. The cessna 208 that [fly this route] always file a route that comes to within less than 2.5 miles of the restricted areas. There isn't a good fix out there for them to file on the west side of that airspace without going a good deal out of their way. Controllers always just set them up on a vector; which increases our workload.

Original NASA ASRS Text

Title: ZMP Controller described an unauthorized restricted airspace entry when an IFR aircraft failed to respond to ATC calls; apparently due to equipment malfunctions.

Narrative: Cessna 208 departed PLN and was flying the usual route. When the aircraft was just north of GLR; I noticed he was very slightly left of course and needed to be turned for military airspace. The R-side tried numerous times broadcasting [to] Cessna 208; 'Turn 15 degrees right;' with no reply. Cessna 208 was on a good frequency and should not have had issues hearing the call. Cessna 208 penetrated the restricted airspace and shortly after we lost his transponder. We tried to relay through another aircraft to reach the Cessna 208. We got him back on frequency a few minutes later. He responded that he had an issue with his radio and lost his transponder and that he smelled something burning. He was turned out of the airspace and identified on a primary target with no further incidences. The Cessna 208 that [fly this route] always file a route that comes to within less than 2.5 miles of the restricted areas. There isn't a good fix out there for them to file on the west side of that airspace without going a good deal out of their way. Controllers always just set them up on a vector; which increases our workload.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	953123
Time
Date	201106
Local Time Of Day	0001-0600
Place
Locale Reference	GLR.Airport
State Reference	MI
Environment
Light	Night
Aircraft 1
Make Model Name	Caravan Undifferentiated
Operating Under FAR Part	Part 135
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Communication Systems
Person 1
Function	Enroute
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	Aircraft Equipment Problem Critical Airspace Violation All Types

ZMP controller described an unauthorized restricted airspace entry when an IFR aircraft failed to respond to ATC calls; apparently due to equipment malfunctions.