A CORPORATE JET'S FLC BECAME DISTRACTED DURING THE CLB; AND FAILED TO COMPLETE THE TRANSITION CHKS; NAMELY; RESETTING THE ALTIMETERS. THE ERROR CAUSED A DEV OF 550 FT; WHICH WAS NOT VERBALLY NOTED BY ATC.

Narrative

ON A FLT FROM PDK TO HPN (WHITEPLAINS; NY) WE WERE CLRED TO CLB TO FL200. DURING THE CLBOUT; WE BECAME PREOCCUPIED WITH ATC COMS AND THE NEW FMS SYS; ON BOARD THE ACFT. AS A RESULT OF THIS; WE BOTH NEGLECTED TO SET THE ALTIMETER TO 29.92. WHEN WE LEVELED AT FL200; WE TOLD ATC WE WERE LEVEL FL200; AND AT THAT MOMENT; REALIZED WE HAD NOT CHANGED THE ALTIMETER TO 29.92 FROM ABOUT 30.47. WE SLOWLY SET IT TO 29.92 AND NOTHING WAS SAID. I FEEL THE PREOCCUPATION WITH ATC AND THE NEW FMS WERE CONTRIBUTING FACTORS; AND THE NEXT TIME WE SHOULD STICK WITH BASIC FLYING AND THE TASK AT HAND. SUPPLEMENTAL INFO FROM ACN 298838: CHALLENGER ACFT WHILE CLBING OUT OF PDK; WE THE CREW WERE DISTRACTED BY OUR NEW FMS; AND ATC ADVISORIES OF A BRASILIA 1000 FT BELOW US. IN THIS CONFUSING AND BUSY ATMOSPHERE; WE NEGLECTED TO DO OUR TRANSITION CHKLIST; WHICH CALLS FOR US TO SET OUR ALTIMETERS TO 29.92 IN THROUGH FL180; PLUS TURN OUR LNDG AND TAXI LIGHTS OFF. THE PNF AND I THEN PROCEEDED TO SLOWLY RE-SET OUR ALTIMETERS TO 29.92; TRYING TO KEEP FL200 AT ALL TIMES IN OUR ALTIMETERS. BOTH HEADS IN COCKPIT IS NO GOOD. BASIC AIRMANSHIP IS THE KEY; HERE. IF CONFUSED WITH FMS - GO BACK TO BASICS.