Narrative:

In our operation, the PNF works the radios and runs the checklists while the PF has control of the airplane and calls the shots. Although I am classified as a copilot, I am essentially the PIC on legs that I am flying, with the captain monitoring my actions. This prepares me for the role of captain. On the flight specified, I was to be the PF while the captain worked the radios. The WX was good VFR, but we filed IFR for traffic sep. In our airplane, I could not hear his xmissions to center for lack of sidetone. During other times I could hear him over the headset via the intercom. At times I would have to ask him what he had said to ZKC if I wasn't certain. After a period of cruise flight at 12000', it was time to descend. I asked the captain to request lower. Center cleared us for the descent to 4800'. About 20 mi from the airport, the captain heard his roommate on the destination unicom and started a conversation with him. At 4800' we were within 2 mi of the airport. I started down to the 4100' pattern altitude assuming that the captain had reported the airport in sight. I was monitoring both frequencys and both were going at the same time making it difficult to understand either one. After reaching pattern I was directly over the airport, whereupon the captain made the comment that center did not clear me from 4800' for the visibility approach. I was startled that he was not paying attention to the task at hand but instead carrying on a conversation with a friend. I would have been better off doing my own radio work, thus avoiding some confusion. Cockpit coordination is important if the duties are going to be split up. The coordination was very poor on this flight and it caused me to go below an assigned altitude by 700'. Also, having transmitter sidetone from the captain's side would have been helpful.

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Original NASA ASRS Text

Title: AIR AMBULANCE DESCENDED 700' BELOW ASSIGNED ALT.

Narrative: IN OUR OPERATION, THE PNF WORKS THE RADIOS AND RUNS THE CHKLISTS WHILE THE PF HAS CONTROL OF THE AIRPLANE AND CALLS THE SHOTS. ALTHOUGH I AM CLASSIFIED AS A COPLT, I AM ESSENTIALLY THE PIC ON LEGS THAT I AM FLYING, WITH THE CAPT MONITORING MY ACTIONS. THIS PREPARES ME FOR THE ROLE OF CAPT. ON THE FLT SPECIFIED, I WAS TO BE THE PF WHILE THE CAPT WORKED THE RADIOS. THE WX WAS GOOD VFR, BUT WE FILED IFR FOR TFC SEP. IN OUR AIRPLANE, I COULD NOT HEAR HIS XMISSIONS TO CENTER FOR LACK OF SIDETONE. DURING OTHER TIMES I COULD HEAR HIM OVER THE HEADSET VIA THE INTERCOM. AT TIMES I WOULD HAVE TO ASK HIM WHAT HE HAD SAID TO ZKC IF I WASN'T CERTAIN. AFTER A PERIOD OF CRUISE FLT AT 12000', IT WAS TIME TO DSND. I ASKED THE CAPT TO REQUEST LOWER. CENTER CLRED US FOR THE DSCNT TO 4800'. ABOUT 20 MI FROM THE ARPT, THE CAPT HEARD HIS ROOMMATE ON THE DEST UNICOM AND STARTED A CONVERSATION WITH HIM. AT 4800' WE WERE WITHIN 2 MI OF THE ARPT. I STARTED DOWN TO THE 4100' PATTERN ALT ASSUMING THAT THE CAPT HAD RPTED THE ARPT IN SIGHT. I WAS MONITORING BOTH FREQS AND BOTH WERE GOING AT THE SAME TIME MAKING IT DIFFICULT TO UNDERSTAND EITHER ONE. AFTER REACHING PATTERN I WAS DIRECTLY OVER THE ARPT, WHEREUPON THE CAPT MADE THE COMMENT THAT CENTER DID NOT CLR ME FROM 4800' FOR THE VIS APCH. I WAS STARTLED THAT HE WAS NOT PAYING ATTN TO THE TASK AT HAND BUT INSTEAD CARRYING ON A CONVERSATION WITH A FRIEND. I WOULD HAVE BEEN BETTER OFF DOING MY OWN RADIO WORK, THUS AVOIDING SOME CONFUSION. COCKPIT COORD IS IMPORTANT IF THE DUTIES ARE GOING TO BE SPLIT UP. THE COORD WAS VERY POOR ON THIS FLT AND IT CAUSED ME TO GO BELOW AN ASSIGNED ALT BY 700'. ALSO, HAVING XMITTER SIDETONE FROM THE CAPT'S SIDE WOULD HAVE BEEN HELPFUL.

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.