Narrative:

While at cruise at 4000 ft indicated (MSL) about 40 NM from msp on ZMP frequency 128.6, while flying on autoplt for nearly 2 hours, I closed my eyes to rest prior to making a landing at msp. I entered a dreamlike state wherein I could hear radio communications in my headset, but I lacked the situational awareness to respond to them. I had impairment of my perception of the passage of time for an estimated 45 NM or about 15 mins. When I regained my situational awareness, I was 10-15 NM northwest of msp. I called the center to re-establish communications and was given a radar vector back to the airport, a descent in altitude, and a handoff to a local controller. I arrived and landed at the airport runway 30L without further complications or incident. A longer than normal flight due to strong headwinds. Extremely clear flight conditions with numerous shooting stars. Extremely cold air temperatures with dry cabin heated air. Later than normal flight departure time, very little radio communication traffic, long periods of silence except for engine drone. Pilot did not have a sense of fatigue when incident occurred, but eyes were hot, dry and tired from 2 hour flight. Pilot should have advised company aircraft in area prior to resting or taking rest period.

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Original NASA ASRS Text

Title: A C208-B ATX PLT, DEST ARPT MSP, FAILS TO MAINTAIN RADIO CONTACT WITH ATC FROM 40 MI SE OF MSP TO 15 MI NW OF MSP, MN.

Narrative: WHILE AT CRUISE AT 4000 FT INDICATED (MSL) ABOUT 40 NM FROM MSP ON ZMP FREQ 128.6, WHILE FLYING ON AUTOPLT FOR NEARLY 2 HRS, I CLOSED MY EYES TO REST PRIOR TO MAKING A LNDG AT MSP. I ENTERED A DREAMLIKE STATE WHEREIN I COULD HEAR RADIO COMS IN MY HEADSET, BUT I LACKED THE SITUATIONAL AWARENESS TO RESPOND TO THEM. I HAD IMPAIRMENT OF MY PERCEPTION OF THE PASSAGE OF TIME FOR AN ESTIMATED 45 NM OR ABOUT 15 MINS. WHEN I REGAINED MY SITUATIONAL AWARENESS, I WAS 10-15 NM NW OF MSP. I CALLED THE CTR TO RE-ESTABLISH COMS AND WAS GIVEN A RADAR VECTOR BACK TO THE ARPT, A DSCNT IN ALT, AND A HDOF TO A LCL CTLR. I ARRIVED AND LANDED AT THE ARPT RWY 30L WITHOUT FURTHER COMPLICATIONS OR INCIDENT. A LONGER THAN NORMAL FLT DUE TO STRONG HEADWINDS. EXTREMELY CLR FLT CONDITIONS WITH NUMEROUS SHOOTING STARS. EXTREMELY COLD AIR TEMPS WITH DRY CABIN HEATED AIR. LATER THAN NORMAL FLT DEP TIME, VERY LITTLE RADIO COM TFC, LONG PERIODS OF SILENCE EXCEPT FOR ENG DRONE. PLT DID NOT HAVE A SENSE OF FATIGUE WHEN INCIDENT OCCURRED, BUT EYES WERE HOT, DRY AND TIRED FROM 2 HR FLT. PLT SHOULD HAVE ADVISED COMPANY ACFT IN AREA PRIOR TO RESTING OR TAKING REST PERIOD.

Data retrieved from NASA's ASRS site as of July 2007 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.