Date: 201209
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Champion Citabria Undifferentiated
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Personal
Flight phase: Cruise
Airspace: Class E ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Powerplant Fuel System
Component problem: Improperly Operated
Reporter organization: Personal
Reporter function: Pilot Flying; Single Pilot
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Human factors: Human-Machine Interface; Situational Awareness; Training / Qualification
Anomaly: Aircraft Equipment Problem Critical; Inflight Event / Encounter Fuel Issue
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Diverted; Flight Crew Landed in Emergency Condition
Contributing factors: Aircraft; Human Factors; Weather
Primary problem: Ambiguous

Narrative: I purchased a Citabria Explorer; model 7GCBC in ZZZ. For insurance requirements I received a 1 hour CFI checkout in the aircraft on the same day. The aircraft had 251 hours total time and I had just had a local pre-purchase examination completed on it. A couple of days later; I departed for my home base in ZZZ1. After spending a night in ZZZ2; I departed for ZZZ1; flying direct to ZZZ3; for gas. I had been flying at 6;500 FT over the Midwest and at 12;500 FT in ZZZ2. During the trip; the O-320 engine had been burning 8-9 gallons per hour; which is normal for that engine. Due to thunderstorms moving to the northeast; I planned to head southwest for the next fuel stop; 310 NM away. I planned 3.5 hours for the trip and filled the plane to the top myself. The half way point was ZZZ4. The fuel gauges at this point were a little lower than the two hour mark was the day before. I would have stopped to fuel in ZZZ4 but there was a large thunderstorm over the field; so I kept on; feeling I had plenty of reserve. I leaned the mixture to the approximate EGT's I had been using; 335-350; which I estimated was just rich of peak. About 80 NM I began getting concerned about the fuel state. I overflew a long; paved private strip with Xs on each end. I would have landed there to see if the building was occupied where I might get a little gas; but was worried if it was unoccupied I would have wasted 5 gallons in the descent and subsequent climb. About 8 NM from destination the engine started to sputter. I was about 10;500 FT and could keep the engine occasionally running by rocking the wings and sloshing the remaining fuel around. About 2 NM from the airport the engine quit for good but I was still about 8;500 FT [(5;500 foot airport)] and thought I'd make the runway; in spite of the 20 KT headwind. As I got down to within 300 FT above the ground; perhaps 200-300 yards from the threshold; I felt it was too close for comfort and deviated 90 degrees to the right to land on the state highway at the northern border of the airport. There were no vehicles in sight for miles. I landed on it and pushed the plane off to the side of the pavement. After 10 minutes of walking to the airport; I was given a ride. After an hour of phone calls; the Airport Manager came out and gave me 5 gallons of gas. When we returned to the plane; the highway patrol was there. I put in the gas; pushed the plane back onto the roadway and taxied it a quarter mile on the highway escorted by the highway patrol; to the airport entrance and from there up the airport road into the tarmac. The Manager then put the plane in his hangar for the night. The next morning I gassed up there and flew it home. The highway patrol wrote an 'incident report' on it. There was no damage to the plane or any property. The navigation equipment in the plane is a Garmin 250XL and it has a single probe EGT/CHT gauge. Fuel capacity is the standard 36 gallons. I was the sole occupant and carried perhaps 50 pounds of luggage. I don't know why the engine burned 10 gallons per hour on this leg. At 3 hours and 35 minutes it quit and I had filled it right to the top in ZZZ3. The mixture knob is inexact; but the CHT's were similar to what it had been reading while using 8-9 gallons an hour. I have 650 hours total time in taildraggers and 250 hours in Super Cubs; similar to the Citabria. However; those hours were from many many years ago.




Synopsis: Citabria pilot reports running out of fuel in his newly purchased aircraft and landing on a highway just short of his destination. The flight was planned for 3.5 hours and the 36 gallon tank ran dry at 3 hours and 35 minutes.