Narrative:

We were taxiing to runway 11R at msp international. We use communication 1 for ATC communication on the medium large transport. Prior to takeoff we preset the departure control frequency and tower frequency on the same communication unit and then just toggle from one to the other. As we neared the runway I confirmed that the departure control frequency was set on the left side. The tower cleared us into position and hold while an aircraft finished his landing roll and we referenced the next aircraft on a 3-4 mi final. One of the last items on our before takeoff mechanical checklist requires the first officer to push the takeoff confign button to confirm a normal confign message prior to departure. We were in position on the runway about 15-25 seconds and heard no tower communications to anybody. Realizing the frequency was too quiet, I checked the frequency on the #1 communication unit. The toggle had been flipped over to the departure frequency. I flipped the toggle back, called the tower and was cleared for takeoff. The aircraft on final was forced to execute a go around. We concluded that while pressing the takeoff confign button the first officer bumped the communication #1 toggle over to the departure control side. The takeoff confign button and the communication 1 panel are side-by-side about 2 inches apart.

Google
 

Original NASA ASRS Text

Title: MLG LOST COM WHILE HOLDING IN POS ON THE RWY CAUSING AN ACFT ON APCH TO GAR.

Narrative: WE WERE TAXIING TO RWY 11R AT MSP INTL. WE USE COM 1 FOR ATC COM ON THE MLG. PRIOR TO TKOF WE PRESET THE DEP CTL FREQ AND TWR FREQ ON THE SAME COM UNIT AND THEN JUST TOGGLE FROM ONE TO THE OTHER. AS WE NEARED THE RWY I CONFIRMED THAT THE DEP CTL FREQ WAS SET ON THE L SIDE. THE TWR CLRED US INTO POS AND HOLD WHILE AN ACFT FINISHED HIS LNDG ROLL AND WE REFED THE NEXT ACFT ON A 3-4 MI FINAL. ONE OF THE LAST ITEMS ON OUR BEFORE TKOF MECHANICAL CHKLIST REQUIRES THE FO TO PUSH THE TKOF CONFIGN BUTTON TO CONFIRM A NORMAL CONFIGN MESSAGE PRIOR TO DEP. WE WERE IN POS ON THE RWY ABOUT 15-25 SECONDS AND HEARD NO TWR COMS TO ANYBODY. REALIZING THE FREQ WAS TOO QUIET, I CHKED THE FREQ ON THE #1 COM UNIT. THE TOGGLE HAD BEEN FLIPPED OVER TO THE DEP FREQ. I FLIPPED THE TOGGLE BACK, CALLED THE TWR AND WAS CLRED FOR TKOF. THE ACFT ON FINAL WAS FORCED TO EXECUTE A GAR. WE CONCLUDED THAT WHILE PRESSING THE TKOF CONFIGN BUTTON THE FO BUMPED THE COM #1 TOGGLE OVER TO THE DEP CTL SIDE. THE TKOF CONFIGN BUTTON AND THE COM 1 PANEL ARE SIDE-BY-SIDE ABOUT 2 INCHES APART.

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.