Date: 201306
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: Mixed
Weather elements / visibility: Cloudy; Icing; 10
Light: Daylight
Aircraft: Amateur/Home Built/Experimental
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Personal
Flight phase: Cruise
Airspace: Class E ZZZ
ATC / advisory: Center ZZZ
Reporter organization: Personal
Reporter function: Pilot Flying; Single Pilot
Reporter qualification: Flight Crew Private
Human factors: Training / Qualification; Time Pressure; Situational Awareness; Confusion; Workload
Anomaly: Deviation / Discrepancy - Procedural Other / Unknown; Inflight Event / Encounter VFR In IMC; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Diverted
Contributing factors: Human Factors; Weather
Primary problem: Human Factors

Narrative: In terms of the chain of events: I would say that the fact that my first destination was overcast at 5;000 that morning should have been a red flag leading us to consider finding a way farther south for a fuel stop; or scrub the flight. Given the terrain in the area; even had we gotten under the overcast; there was no guarantee that the overcast was 5;000 everywhere; or that we could safely maneuver around the higher terrain as one could easily do in VFR conditions. Upon landing and checking in with flight service; it was confirmed that the ceilings remained reported at 5;000 AGL at [our next stop]; but a PIREP by a Maule over [the highway] just north of [the airport] had him following the highway at 1;500 FT; with visibility about 6 miles and deteriorating. [The airport] was reporting VFR; but this did not sound like VFR to either the Briefer or me. The weather south did not sound any better; either; so we decided not to continue to find a safe route to our final destination; and instead flew back to [out departure]. What is not clear to me was exactly when it was during the flight that a decision could have been made to abort the flight and head to our alternate. The clouds did not seem unusual for that time of year in that location. I was confident that I could get under the overcast without a problem; refuel; and continue to a clear enroute airport; where conditions would have allowed continued flight to the fly-in. The decision point had to have been at the very beginning of the flight with a final check with flight service prior to launch. Even then; [our planned stop] was reporting VFR; overcast 5;000. Plenty of room; one would think; but not in those hills from the direction we were approaching and not if you have to depend on getting under the overcast. The chain should have ended before the flight was initiated. During flight; there was really no strong deterrent. It seemed like a normal VFR flight for that area until it was obvious conditions were unacceptable. The time from 'this looks possible' to 'this is not safe' was a matter of 1 to 2 minutes at most.




Synopsis: A non instrument rated Glastar GS-1 pilot flew into IMC and requested ATC assistant to fly the non IFR equipped aircraft to a previously selected alternate airport because his destination was overcast.