Narrative:

I was en route from off to cbf for night landing currency. Departing off, I was in contact with oma approach on 120.1. When I estimated I was approximately 5 mi southwest of cbf, approach cleared me to change radio frequency and to squawk 1200. I switched to cbf, 122.8, and started a descent out of 3000 ft MSL. The base of the class C outer ring airspace is 2500 ft MSL. I had let down below 2500 ft MSL and was looking for the cbf airport. The problem started when I inadvertently overflew the cbf airport without seeing the airport. I was now 3-4 mi northeast of cbf and started doing turns to locate cbf. While looking for cbf, I did not notice my altitude slowly increasing. I re-entered the outer ring of the class C airspace from the bottom. The contributing factor was my inattn to my altitude increase while looking for cbf. I did not realize I had violated the class C airspace until oma contacted me on the cbf CTAF and advised me of what I had done. In hindsight, I should have recontacted oma approach to request assistance in locating cbf. After I landed at off, I telephoned oma approach to further clarify any questions which they may have had.

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Original NASA ASRS Text

Title: PLT OF A BEECH T34, MENTOR, DURING A NIGHT CURRENCY FLT, INADVERTENTLY CLBED INTO CLASS C AIRSPACE WHILE LOOKING FOR HIS DEST ARPT. THE ARPT (NON TWR) WAS LOCATED BENEATH THE CLASS C AIRSPACE.

Narrative: I WAS ENRTE FROM OFF TO CBF FOR NIGHT LNDG CURRENCY. DEPARTING OFF, I WAS IN CONTACT WITH OMA APCH ON 120.1. WHEN I ESTIMATED I WAS APPROX 5 MI SW OF CBF, APCH CLRED ME TO CHANGE RADIO FREQ AND TO SQUAWK 1200. I SWITCHED TO CBF, 122.8, AND STARTED A DSCNT OUT OF 3000 FT MSL. THE BASE OF THE CLASS C OUTER RING AIRSPACE IS 2500 FT MSL. I HAD LET DOWN BELOW 2500 FT MSL AND WAS LOOKING FOR THE CBF ARPT. THE PROB STARTED WHEN I INADVERTENTLY OVERFLEW THE CBF ARPT WITHOUT SEEING THE ARPT. I WAS NOW 3-4 MI NE OF CBF AND STARTED DOING TURNS TO LOCATE CBF. WHILE LOOKING FOR CBF, I DID NOT NOTICE MY ALT SLOWLY INCREASING. I RE-ENTERED THE OUTER RING OF THE CLASS C AIRSPACE FROM THE BOTTOM. THE CONTRIBUTING FACTOR WAS MY INATTN TO MY ALT INCREASE WHILE LOOKING FOR CBF. I DID NOT REALIZE I HAD VIOLATED THE CLASS C AIRSPACE UNTIL OMA CONTACTED ME ON THE CBF CTAF AND ADVISED ME OF WHAT I HAD DONE. IN HINDSIGHT, I SHOULD HAVE RECONTACTED OMA APCH TO REQUEST ASSISTANCE IN LOCATING CBF. AFTER I LANDED AT OFF, I TELEPHONED OMA APCH TO FURTHER CLARIFY ANY QUESTIONS WHICH THEY MAY HAVE HAD.

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.