Narrative:

I had been giving flight instruction for only one month and in this particular flight I was using a new intercom that I had recently bought. The airport was very busy with a few aircraft doing touch and goes and another 3 on the east run-up area ready for touch and goes, besides the normal traffic. There were a few misunderstandings between ground control and several airplanes concerning who was who. Ground cleared us to taxi to runway 27L and a few moments later to do a 180 degree turn and taxi to 27R. I was having some problem understanding the communications, and looked inside for a moment to check the intercom. I looked outside and found to my disbelief that the student had crossed the holding line and we were now on the runway 27R. Almost immediately ground told us that we didn't have a clearance to be there and then we were cleared for takeoff. The quality first officer communication was not good and after one touch and go I requested a full stop. Then, as we cleared the runway we requested a clearance to taxi to the ramp with ground and understood that that had been given. I had a problem with communications and informed ATC of that. Later I came to find out that ground had instructed us to hold our position for a landing helicopter which we didn't do. In a very short flight there had been two mishaps, which didn't affect the safety of any traffic to the best of my knowledge but could have been very serious. Contributing factors were the confusion between ground control and several aircraft on the east run-up area to who was number one, two and three, the issuance of unexpected and unnecessary clrncs, and a failing intercom.

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Original NASA ASRS Text

Title: SMA ON TRAINING MISSION INADVERTENTLY ENTERED ACTIVE RWY WITHOUT AUTHORIZATION. FAILED TO HOLD FOR LNDG HELICOPTER.

Narrative: I HAD BEEN GIVING FLT INSTRUCTION FOR ONLY ONE MONTH AND IN THIS PARTICULAR FLT I WAS USING A NEW INTERCOM THAT I HAD RECENTLY BOUGHT. THE ARPT WAS VERY BUSY WITH A FEW ACFT DOING TOUCH AND GOES AND ANOTHER 3 ON THE E RUN-UP AREA READY FOR TOUCH AND GOES, BESIDES THE NORMAL TFC. THERE WERE A FEW MISUNDERSTANDINGS BETWEEN GND CTL AND SEVERAL AIRPLANES CONCERNING WHO WAS WHO. GND CLRED US TO TAXI TO RWY 27L AND A FEW MOMENTS LATER TO DO A 180 DEG TURN AND TAXI TO 27R. I WAS HAVING SOME PROBLEM UNDERSTANDING THE COMS, AND LOOKED INSIDE FOR A MOMENT TO CHECK THE INTERCOM. I LOOKED OUTSIDE AND FOUND TO MY DISBELIEF THAT THE STUDENT HAD CROSSED THE HOLDING LINE AND WE WERE NOW ON THE RWY 27R. ALMOST IMMEDIATELY GND TOLD US THAT WE DIDN'T HAVE A CLRNC TO BE THERE AND THEN WE WERE CLRED FOR TKOF. THE QUALITY FO COM WAS NOT GOOD AND AFTER ONE TOUCH AND GO I REQUESTED A FULL STOP. THEN, AS WE CLRED THE RWY WE REQUESTED A CLRNC TO TAXI TO THE RAMP WITH GND AND UNDERSTOOD THAT THAT HAD BEEN GIVEN. I HAD A PROBLEM WITH COMS AND INFORMED ATC OF THAT. LATER I CAME TO FIND OUT THAT GND HAD INSTRUCTED US TO HOLD OUR POSITION FOR A LNDG HELI WHICH WE DIDN'T DO. IN A VERY SHORT FLT THERE HAD BEEN TWO MISHAPS, WHICH DIDN'T AFFECT THE SAFETY OF ANY TFC TO THE BEST OF MY KNOWLEDGE BUT COULD HAVE BEEN VERY SERIOUS. CONTRIBUTING FACTORS WERE THE CONFUSION BETWEEN GND CTL AND SEVERAL ACFT ON THE E RUN-UP AREA TO WHO WAS NUMBER ONE, TWO AND THREE, THE ISSUANCE OF UNEXPECTED AND UNNECESSARY CLRNCS, AND A FAILING INTERCOM.

Data retrieved from NASA's ASRS site as of August 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.