Narrative:

I took off from L37, an uncontrolled airport after filing for IFR clearance to bjc. After takeoff I contacted ZLA and advised I was IFR off L37 climbing to FL190. ZLA acknowledged. I proceeded on course and climbed to FL190. The controller told me I had no clearance to FL190 and then cleared me to bjc via hbu and powdr arrival. I mistakenly thought I was cleared as filed but now realize you must have the clearance before entering class a airspace. I am not normally filing IFR from an uncontrolled airport and am accustomed to receiving clearance prior to takeoff.

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Original NASA ASRS Text

Title: TKOF FROM UNCTLED ARPT AND CONTACTED CTR ADVISING OFF THE ARPT AND CTR ACKNOWLEDGED. RPTR ENTERED CLASS A WITHOUT CLRNC. RPTR THOUGHT WHEN CTR ACKNOWLEDGED THAT PROVIDED CLRNC, BUT APPARENTLY CTR DIDN'T KNOW RPTR DIDN'T HAVE THE IFR CLRNC. CTLR ADVISED RPTR, THOUGH, WHEN HE CLBED TO FL190.

Narrative: I TOOK OFF FROM L37, AN UNCTLED ARPT AFTER FILING FOR IFR CLRNC TO BJC. AFTER TKOF I CONTACTED ZLA AND ADVISED I WAS IFR OFF L37 CLBING TO FL190. ZLA ACKNOWLEDGED. I PROCEEDED ON COURSE AND CLBED TO FL190. THE CTLR TOLD ME I HAD NO CLRNC TO FL190 AND THEN CLRED ME TO BJC VIA HBU AND POWDR ARR. I MISTAKENLY THOUGHT I WAS CLRED AS FILED BUT NOW REALIZE YOU MUST HAVE THE CLRNC BEFORE ENTERING CLASS A AIRSPACE. I AM NOT NORMALLY FILING IFR FROM AN UNCTLED ARPT AND AM ACCUSTOMED TO RECEIVING CLRNC PRIOR TO TKOF.

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.