Narrative:

We had deplaned our passenger and got our clearance for our last leg and expected a clearance to taxi to one of the '5's' (runways 5L or 5R), which were the active runways, when ground controller asked if we would like runway 32. Because it would shorten our taxi considerably, we accepted, taxied to runway 32 and departed normally and began to climb on runway heading to 5000 ft as according to our clearance. After contacting departure and stating our altitude and that we were climbing to 5000 ft, departure told us of traffic at our 2 O'clock and about 5 mi, right to left at 6000 ft. We immediately got visual on the traffic and as we were climbing out of about 3500 ft to 4000 ft, I remarked to my first officer that it didn't look like we would have 1000 ft of separation with the traffic if we leveled at 5000 ft underneath it. I slowed the rate of climb to about 800 FPM as we kept our eyes on the traffic. It passed right to left in front of us about 1 or 2 mi ahead. At that time, it was very clear our separation was less than 1000 ft and departure asked the traffic if they had us in sight. They said they did, and then departure gave them a visual clearance to continue their descent to 4000 ft. At that moment we went through the wake of our traffic as we leveled at 5000 ft only a mi or so behind it. We then inquired with departure why we were not informed that the traffic was in a descent to 4000 ft. Departure was as surprised as we were and asked if our climb clearance was to 2500 ft. It was not. It became clear that in the switch of runways, a change of initial climb altitude was not passed along to us. Also, departure did not catch the error and allowed us to climb towards descending traffic (a B737). If conditions were IMC and we were 10 seconds ahead of schedule, an accident would have occurred.

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Original NASA ASRS Text

Title: LTSS OCCURRED WHEN A B737 WAS CLRED TO DSND THROUGH THE ALT OF A CLBING CORPORATE JET. DEP CTLR EXPECTED CORP JET TO LEVEL AT A LOWER ALT.

Narrative: WE HAD DEPLANED OUR PAX AND GOT OUR CLRNC FOR OUR LAST LEG AND EXPECTED A CLRNC TO TAXI TO ONE OF THE '5'S' (RWYS 5L OR 5R), WHICH WERE THE ACTIVE RWYS, WHEN GND CTLR ASKED IF WE WOULD LIKE RWY 32. BECAUSE IT WOULD SHORTEN OUR TAXI CONSIDERABLY, WE ACCEPTED, TAXIED TO RWY 32 AND DEPARTED NORMALLY AND BEGAN TO CLB ON RWY HEADING TO 5000 FT AS ACCORDING TO OUR CLRNC. AFTER CONTACTING DEP AND STATING OUR ALT AND THAT WE WERE CLBING TO 5000 FT, DEP TOLD US OF TFC AT OUR 2 O'CLOCK AND ABOUT 5 MI, R TO L AT 6000 FT. WE IMMEDIATELY GOT VISUAL ON THE TFC AND AS WE WERE CLBING OUT OF ABOUT 3500 FT TO 4000 FT, I REMARKED TO MY FO THAT IT DIDN'T LOOK LIKE WE WOULD HAVE 1000 FT OF SEPARATION WITH THE TFC IF WE LEVELED AT 5000 FT UNDERNEATH IT. I SLOWED THE RATE OF CLB TO ABOUT 800 FPM AS WE KEPT OUR EYES ON THE TFC. IT PASSED R TO L IN FRONT OF US ABOUT 1 OR 2 MI AHEAD. AT THAT TIME, IT WAS VERY CLR OUR SEPARATION WAS LESS THAN 1000 FT AND DEP ASKED THE TFC IF THEY HAD US IN SIGHT. THEY SAID THEY DID, AND THEN DEP GAVE THEM A VISUAL CLRNC TO CONTINUE THEIR DSCNT TO 4000 FT. AT THAT MOMENT WE WENT THROUGH THE WAKE OF OUR TFC AS WE LEVELED AT 5000 FT ONLY A MI OR SO BEHIND IT. WE THEN INQUIRED WITH DEP WHY WE WERE NOT INFORMED THAT THE TFC WAS IN A DSCNT TO 4000 FT. DEP WAS AS SURPRISED AS WE WERE AND ASKED IF OUR CLB CLRNC WAS TO 2500 FT. IT WAS NOT. IT BECAME CLR THAT IN THE SWITCH OF RWYS, A CHANGE OF INITIAL CLB ALT WAS NOT PASSED ALONG TO US. ALSO, DEP DID NOT CATCH THE ERROR AND ALLOWED US TO CLB TOWARDS DSNDING TFC (A B737). IF CONDITIONS WERE IMC AND WE WERE 10 SECONDS AHEAD OF SCHEDULE, AN ACCIDENT WOULD HAVE OCCURRED.

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.