Narrative:

ATC frequency confusion. Pushback, engine start, pre takeoff checklist accomplished normally. Began aircraft movement from the gate toward taxiway H1. First officer tried to call for taxi on 121.8, frequency blocked. Continuing to monitor frequency for several mins while a lengthy clearance/readback was being issued. I asked first officer to check frequency. He verified we were on ground, not clearance. We checked for alternate ground frequency. Approaching the taxiway H1 throat while still on the ramp, I asked the first officer to try tower on 118.45. Tower operator hesitated, then cleared us to 'position and hold runway 17.' as we turned onto the runway he asked us to verify our call sign as 'company number.' we replied 'affirmative' and we were cleared to take off. During climb out, we were instructed to call mco tower on arrival in ZZZ. I called the mco controller in ZZZ. He wanted to know why we had not contacted ground for taxi clearance. I explained the clearance confusion and asked if ground/clearance were combined (not on mco ATIS). He replied negative, but ground frequency was 'clobbered' with a full clearance rerte and readback for chicago flts. He acknowledged the confusion, said 'no harm, no foul,' and asked us to explain that we were unable to talk to ground when switching directly to tower in the future. The very short taxi distance from the gate to runway 17, coupled with the lengthy tie-up of ground frequency, compounds the confusion. An alternate published secondary ground frequency at mco would be a big help. No other aircraft were maneuvering in our vicinity or holding for takeoff runway 17. Supplemental information from acn 561977: after completion on pretkof checklist to the line, I attempted to contact ground for taxi on 121.8. Frequency was busy with a full clearance readback. Captain asked if I was on ground frequency and I replied we were. With no other ground frequencys available, I was about to ask if we should switch to tower (mco departing runway 17, pushed gate) when captain told me to switch and check in with tower. As captain held short of taxiway H1, I called tower on 118.45 (frequency for runway 17/35). Tower acknowledged and told us to position and hold on runway 17. Crossing hold short line, tower asked us to confirm our call sign as 'company number.' (my first indication that everything was not ok.) after responding, we were cleared for takeoff. On departure, mco departure requested we call tower when we got to ZZZ. After landing ZZZ, captain called tower who said they wanted to know why we did not talk to ground. With airside 2 ramp not controled by ground and monitoring ground up to taxiway H1 for a runway 17 departure, I saw no problem and agreed when captain requested I check in with tower on 128.45 as we held on taxiway H1.

Related reports:

Google
 

Original NASA ASRS Text

Title: B737-700 CREW FOUND GND CTL FREQ BLOCKED AND APPARENTLY BEGAN TAXI BEFORE CONTACTING TWR.

Narrative: ATC FREQ CONFUSION. PUSHBACK, ENG START, PRE TKOF CHKLIST ACCOMPLISHED NORMALLY. BEGAN ACFT MOVEMENT FROM THE GATE TOWARD TXWY H1. FO TRIED TO CALL FOR TAXI ON 121.8, FREQ BLOCKED. CONTINUING TO MONITOR FREQ FOR SEVERAL MINS WHILE A LENGTHY CLRNC/READBACK WAS BEING ISSUED. I ASKED FO TO CHK FREQ. HE VERIFIED WE WERE ON GND, NOT CLRNC. WE CHKED FOR ALTERNATE GND FREQ. APCHING THE TXWY H1 THROAT WHILE STILL ON THE RAMP, I ASKED THE FO TO TRY TWR ON 118.45. TWR OPERATOR HESITATED, THEN CLRED US TO 'POS AND HOLD RWY 17.' AS WE TURNED ONTO THE RWY HE ASKED US TO VERIFY OUR CALL SIGN AS 'COMPANY NUMBER.' WE REPLIED 'AFFIRMATIVE' AND WE WERE CLRED TO TAKE OFF. DURING CLBOUT, WE WERE INSTRUCTED TO CALL MCO TWR ON ARR IN ZZZ. I CALLED THE MCO CTLR IN ZZZ. HE WANTED TO KNOW WHY WE HAD NOT CONTACTED GND FOR TAXI CLRNC. I EXPLAINED THE CLRNC CONFUSION AND ASKED IF GND/CLRNC WERE COMBINED (NOT ON MCO ATIS). HE REPLIED NEGATIVE, BUT GND FREQ WAS 'CLOBBERED' WITH A FULL CLRNC RERTE AND READBACK FOR CHICAGO FLTS. HE ACKNOWLEDGED THE CONFUSION, SAID 'NO HARM, NO FOUL,' AND ASKED US TO EXPLAIN THAT WE WERE UNABLE TO TALK TO GND WHEN SWITCHING DIRECTLY TO TWR IN THE FUTURE. THE VERY SHORT TAXI DISTANCE FROM THE GATE TO RWY 17, COUPLED WITH THE LENGTHY TIE-UP OF GND FREQ, COMPOUNDS THE CONFUSION. AN ALTERNATE PUBLISHED SECONDARY GND FREQ AT MCO WOULD BE A BIG HELP. NO OTHER ACFT WERE MANEUVERING IN OUR VICINITY OR HOLDING FOR TKOF RWY 17. SUPPLEMENTAL INFO FROM ACN 561977: AFTER COMPLETION ON PRETKOF CHKLIST TO THE LINE, I ATTEMPTED TO CONTACT GND FOR TAXI ON 121.8. FREQ WAS BUSY WITH A FULL CLRNC READBACK. CAPT ASKED IF I WAS ON GND FREQ AND I REPLIED WE WERE. WITH NO OTHER GND FREQS AVAILABLE, I WAS ABOUT TO ASK IF WE SHOULD SWITCH TO TWR (MCO DEPARTING RWY 17, PUSHED GATE) WHEN CAPT TOLD ME TO SWITCH AND CHK IN WITH TWR. AS CAPT HELD SHORT OF TXWY H1, I CALLED TWR ON 118.45 (FREQ FOR RWY 17/35). TWR ACKNOWLEDGED AND TOLD US TO POS AND HOLD ON RWY 17. XING HOLD SHORT LINE, TWR ASKED US TO CONFIRM OUR CALL SIGN AS 'COMPANY NUMBER.' (MY FIRST INDICATION THAT EVERYTHING WAS NOT OK.) AFTER RESPONDING, WE WERE CLRED FOR TKOF. ON DEP, MCO DEP REQUESTED WE CALL TWR WHEN WE GOT TO ZZZ. AFTER LNDG ZZZ, CAPT CALLED TWR WHO SAID THEY WANTED TO KNOW WHY WE DID NOT TALK TO GND. WITH AIRSIDE 2 RAMP NOT CTLED BY GND AND MONITORING GND UP TO TXWY H1 FOR A RWY 17 DEP, I SAW NO PROB AND AGREED WHEN CAPT REQUESTED I CHK IN WITH TWR ON 128.45 AS WE HELD ON TXWY H1.

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.