SABRELINER 65 BEGAN PUMPING UNCONDITIONED BLEED AIR INTO CABIN DURING INITIAL CLIMB AFTER TKOF. FLT CREW DECLARED EMER AND RETURNED FOR SUCCESSFUL LNDG.

Narrative

DURING TKOF ROLL; SHORTLY AFTER V1 SPD WAS ATTAINED; 'CABIN HOT' LIGHT ILLUMINATED. AT THE SAME TIME HOT; UNCONDITIONED AIR BEGAN TO FILL CABIN AND THEN COCKPIT. TKOF WAS COMPLETED TO THE N OFF OF ZZZ. INITIAL DEP ROUTING CALLS FOR R TURN TO 340 DEGS UNTIL 870 FT AGL; THEN TURN TO 270 DEGS FOR 16000 FT MSL. SHORTLY AFTER TKOF; THE CABIN AND THEN THE COCKPIT BEGAN TO FILL WITH SMOKE AS THE PF (WHO IS FREQUENT CAPT ON ACFT AND MECH AS WELL) BEGAN TO STEER FOR DEP RTE SEGMENT. AT THE SAME TIME; THERE WAS AN INBOUND ACFT (LEARJET) THAT I HEARD HAD BEEN CLRED TO LAND; BUT WHICH WAS STILL 7 MI N. THE PF BEGAN TO TRY TO FIX THE PROB CAUSING THE HEAT AND SMOKE BUT REMAINED ON THE 340 DEG HDG AND CLBED THROUGH AND BEYOND 870 FT AGL. TWR ATTEMPTED TO TURN US OVER TO DEP; BUT PNF (WHO IS TYPE RATED CONTRACT PLT) ADVISED THAT WE NEEDED AN IMMEDIATE RETURN TO THE ARPT. WE WERE ASKED THE NATURE OF THE PROB; AND PNF ADVISED TO 'STAND BY' AS THE CREW WAS ATTEMPTING TO WORK THE PROB. PF THEN CONFIRMED TO PNF THAT A RETURN WAS NECESSARY GIVEN THE AMOUNT OF HEAT AND SMOKE IN THE CABIN AND COCKPIT. HOWEVER; ONLY A L TURN WOULD BE APPROPRIATE DUE TO RAPIDLY RISING TERRAIN BUT DOING SO WOULD BE A POTENTIAL CONFLICT WITH ARRIVING ACFT. AT THAT TIME; PNF DECLARED AN EMER BECAUSE OF THE UNKNOWN SEVERITY OF THE PROB AND A L TURN WAS COMMENCED. TWR CANCELED THE LNDG CLRNC OF THE ARR ACFT AND CLRED US TO LAND. WE RETURNED AND LANDED WITHOUT INCIDENT. CREW COORD BEGAN TO LACK DURING THE IMMEDIATE DEP SEGMENT AS PF WAS ATTEMPTING TO MANAGE THE ACFT INFLT AND WORK A MECHANICAL PROB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE REPORTER STATED THAT THE SITUATION MADE IT NECESSARY TO DECLARE AN EMER FOR TFC PRIORITY. APPARENTLY; A VALVE MALFUNCTIONED AFTER THE COCKPIT WAS SET UP FOR A PACKS OFF TKOF AT THIS HIGH ALT ARPT. THIS VALVE STUCK; WHICH ALLOWED VERY HOT AIR INTO THE CABIN. ANOTHER ACFT WAS ON APCH AS THIS WAS HAPPENING. TO PREVENT HIM FROM INITIATING HIS DESCENT INTO THE VALLEY ONLY TO BE FORCED TO CLIMB BACK OUT; THE FO DECLARED AN EMER.