ALTDEV ALT EXCURSION.

Narrative

AS WE CLBED TO 10000 FT WE WERE APCHING MXE LEAVING 9000 FT FOR 10000 FT WE WERE GIVEN A HDOF FROM PHL DEP TO ZNY. THE FO CHKED IN FOR ZNY. I WAS SETTING UP FOR THE MXE 278 DEG RADIAL FOR PENEY TO JOIN J-110. THE FO COMMENTED THAT I HAD THE WRONG RADIAL THAT I SHOULD SET IN MXE 284 DEG RADIAL AS HE HAD JUST RECENTLY SET IN. ZNY ACKNOWLEDGED OUR CHK IN AND I THOUGHT; AS I EXPECTED; GAVE US HIGHER. I MEANWHILE TOLD THE FO TO CHK THE RADIAL. AS MXE WAS COMING UP QUICKLY. WHILE HE WAS CHKING HIS CHART I NOTICED THE ALT ALERT WAS STILL SET AT 10000 FT. I ASKED HIM TO VERIFY OUR ALT THAT WE WERE CLRED TO AS I BEGAN PULLING OFF PWR AND LOWERING THE NOSE. CTR VERIFIED OUR CLRNC LIMIT WAS 10000 FT AND ASKED US FOR OUR ALT. AT THAT TIME WE WERE DSNDING THROUGH 10200 FT WHICH WE RPTED. WE HAD GONE AS HIGH AS 10400 FT. THERE WAS TFC IN THE AREA AT 11000 FT. I AM NOT SURE WHAT THE DISTANCE WAS. TCASII WAS ON AND NEVER GAVE A TA OR AN RA. THE CAUSE OF THIS EXCURSION WAS CONFUSION ON BOTH THE FO AND MY PART AS TO WHAT OUR CLRNC WAS. AS IT TURNS OUT I WAS CORRECT ABOUT OUR ROUTING BUT QUESTIONING BY THE FO WHILE CTR WAS TALKING CAUSED ME TO MISS OUR ALT CLRNC AND HEAR WHAT I EXPECTED TO HEAR. WE BECAME VERY BUSY FOR ABOUT 30 SECONDS AND WHILE TRYING TO CLARIFY ROUTING MISSED OUR ALT. MY FIRST THOUGHT FOR A SOLUTION IS TO SAY THE PF SHOULD PAY CLOSE ATTN TO ALT DURING THE LAST 1000 FT OF ALT CHANGE. I FEEL HOWEVER THAT IN THIS INSTANCE THAT AS WE WERE VERY CLOSE TO MAKING A COURSE CHANGE AT THE TIME THE COURSE CHANGE IS JUST AS IMPORTANT AS LEVEL OFF. DEVIATING FROM EITHER ONE CAN CAUSE A CONFLICT.