Narrative:

On our arrival into iah on flight abc, we were told to contact houston tower on frequency 135.15. When we contacted the tower, my first officer and I heard air carrier bcd cleared to land runway 27. My first officer read the clearance to land back. On low approach we noticed a green light signal from the tower. After we landed in iah, we were told to contact ground control. After we contacted ground, we were then told to contact our company ramp frequency. Ramp advised us that we needed to call the tower. Tower told us that they had been calling us numerous times on final and did not hear a response. They asked us if we had received a landing clearance. We told them that we had, and that we also saw the light gun signal. As a memory aid, my first officer and I leave the taxi light off until we hear our landing clearance. On this occurrence, we both reached T turn the taxi light on when we heard our clearance. Our radio functioned properly before and after the occurrence. I do not know if someone else gave us a clearance or if the control tower was not transmitting on the correct frequency or if we did not hear their numerous calls. I talked with the tower on the telephone, and he advised us that there was no problem and thanked us for calling.

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Original NASA ASRS Text

Title: FLC LANDED WITHOUT CLRNC AT IAH.

Narrative: ON OUR ARR INTO IAH ON FLT ABC, WE WERE TOLD TO CONTACT HOUSTON TWR ON FREQ 135.15. WHEN WE CONTACTED THE TWR, MY FO AND I HEARD ACR BCD CLRED TO LAND RWY 27. MY FO READ THE CLRNC TO LAND BACK. ON LOW APCH WE NOTICED A GREEN LIGHT SIGNAL FROM THE TWR. AFTER WE LANDED IN IAH, WE WERE TOLD TO CONTACT GND CTL. AFTER WE CONTACTED GND, WE WERE THEN TOLD TO CONTACT OUR COMPANY RAMP FREQ. RAMP ADVISED US THAT WE NEEDED TO CALL THE TWR. TWR TOLD US THAT THEY HAD BEEN CALLING US NUMEROUS TIMES ON FINAL AND DID NOT HEAR A RESPONSE. THEY ASKED US IF WE HAD RECEIVED A LNDG CLRNC. WE TOLD THEM THAT WE HAD, AND THAT WE ALSO SAW THE LIGHT GUN SIGNAL. AS A MEMORY AID, MY FO AND I LEAVE THE TAXI LIGHT OFF UNTIL WE HEAR OUR LNDG CLRNC. ON THIS OCCURRENCE, WE BOTH REACHED T TURN THE TAXI LIGHT ON WHEN WE HEARD OUR CLRNC. OUR RADIO FUNCTIONED PROPERLY BEFORE AND AFTER THE OCCURRENCE. I DO NOT KNOW IF SOMEONE ELSE GAVE US A CLRNC OR IF THE CTL TWR WAS NOT XMITTING ON THE CORRECT FREQ OR IF WE DID NOT HEAR THEIR NUMEROUS CALLS. I TALKED WITH THE TWR ON THE TELEPHONE, AND HE ADVISED US THAT THERE WAS NO PROB AND THANKED US FOR CALLING.

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.