Narrative:

On jan/xa/99, I was PIC of a hawker. I was designated PNF, and my copilot occupied the left seat and was flying the aircraft. We were on a flight plan from oak to bermuda dunes airport (udd) 13 mi south of palm springs. We had no passenger on board. We had crossed the mountains north of psp at 14000 ft MSL, and had been given clearance to descend to 5000 ft MSL. It was day, VFR with approximately 30 mi of flight visibility. At approximately the psp VOR, we were given a vector heading of 090 degrees by palm springs approach, which the copilot flew. At approximately XA57, psp ATC was inundated with VFR traffic calls, which he attempted to respond to. On our heading, the TCASII system provided 2 TA's which we visually idented and avoided (both small piston engine aircraft). Neither required a heading nor altitude change, but there were no calls from ATC. Approximately 4 mins passed with no further communication to our aircraft, although other aircraft were being provided traffic calls (all apparently small, VFR airplanes). Our vector put us well below the ridgeline of a range of mountains east of psp which we could see approaching. With approximately 20 seconds remaining to ground impact, the area to the right visually and TCASII clear, I instructed the PF to turn right immediately (which he did). There were no breaks in the frequency to contact ATC some 2 mins prior to our turn, and I used the identify button continuously in the last 60 seconds before our turn to attempt to get ATC's attention. During ATC's xmissions 15 seconds prior to our turn, I could distinctly hear an alarm in the backgnd. I am certain this was either a ground proximity alarm or a TA alarm, although I cannot claim that it was specific to our aircraft. 20-30 seconds after the turn, I was able to break into the frequency and informed ATC we were no longer on his vector 'toward the mountains,' that the airport (bermuda dunes) was in sight and we were canceling IFR, and would proceed to the airport VFR. His response, 'report canceling on this frequency or via phone after landing.' I reaffirmed our cancellation and we landed without further incident at XP04. It is clear that the controller lost situational awareness in separation and sequencing of IFR targets under the traffic load. His response indicates that he forgot about our target and it took a moment for him to process any information about us. Although we did not wish to create additional conflicts by acting contrary to our clearance (assigned heading), it became clear that unless we acted quickly, that the controller was not going to provide an amended clearance. Contributing factors were the clear WX in the valley prompting many pilots to fly this day. I see 2 possible ways to have avoided this incident: 1) cancel IFR farther out. This allows the pilot to maneuver for the airport, and if VFR TA's are requested, they can be provided without the constructions of having to follow a clearance. 2) limit controller workload. Each controller must determine a level for which he or she is comfortable working. If the IFR traffic can't be handled properly, then obviously no additional VFR traffic should be accepted for advisories. Supervision is a must to ensure that if the sector gets busy suddenly that the controller does not get overloaded too quickly. I do not think that this case would have happened under IFR conditions for 2 reasons: 1) the number of aircraft would have been greatly reduced. 2) our routing would have taken us south, in the valley to the thermal VOR and reversed course for the VOR approach into bermuda dunes. As a result of maintaining IFR rtes and altitudes, terrain separation would have been provided. Callback conversation with reporter revealed the following information: the reporter called psp tower a few days after the incident and talked with a supervisor. As it turned out, this supervisor had been monitoring in the tracab and observed the incident. The reporter stated that the supervisor 'pulled' the controller and trainee off the control position with the respective tape. Neither the instructor not the trainee had remembered that a descent clearance had been issued and acknowledged by the HS25 flight crew. Both controllers became distraction with VFR traffic calls. The supervisor advised the reporter that he had initiated a facility review of instructor training requirements. Since psp was a training facility, and they presently had 'a lot of trainees,' he also initiated a review of instructor/trainee scheduling and qualifications. The reporter stated that he thought the incident was reviewed in sufficient detail by the psp supervisor that he felt the incident closed. The reporter briefed his company chief pilot.

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Original NASA ASRS Text

Title: HS25 FLC REQUIRED TO INITIATE UNCOORD TRACK DEV WHEN PIC PERCEIVED ATC WAS NOT GOING TO CHANGE ASSIGNED HDG AS ACFT'S TRACK PROCEEDED TOWARDS HIGHER TERRAIN.

Narrative: ON JAN/XA/99, I WAS PIC OF A HAWKER. I WAS DESIGNATED PNF, AND MY COPLT OCCUPIED THE L SEAT AND WAS FLYING THE ACFT. WE WERE ON A FLT PLAN FROM OAK TO BERMUDA DUNES ARPT (UDD) 13 MI S OF PALM SPRINGS. WE HAD NO PAX ON BOARD. WE HAD CROSSED THE MOUNTAINS N OF PSP AT 14000 FT MSL, AND HAD BEEN GIVEN CLRNC TO DSND TO 5000 FT MSL. IT WAS DAY, VFR WITH APPROX 30 MI OF FLT VISIBILITY. AT APPROX THE PSP VOR, WE WERE GIVEN A VECTOR HDG OF 090 DEGS BY PALM SPRINGS APCH, WHICH THE COPLT FLEW. AT APPROX XA57, PSP ATC WAS INUNDATED WITH VFR TFC CALLS, WHICH HE ATTEMPTED TO RESPOND TO. ON OUR HDG, THE TCASII SYS PROVIDED 2 TA'S WHICH WE VISUALLY IDENTED AND AVOIDED (BOTH SMALL PISTON ENG ACFT). NEITHER REQUIRED A HDG NOR ALT CHANGE, BUT THERE WERE NO CALLS FROM ATC. APPROX 4 MINS PASSED WITH NO FURTHER COM TO OUR ACFT, ALTHOUGH OTHER ACFT WERE BEING PROVIDED TFC CALLS (ALL APPARENTLY SMALL, VFR AIRPLANES). OUR VECTOR PUT US WELL BELOW THE RIDGELINE OF A RANGE OF MOUNTAINS E OF PSP WHICH WE COULD SEE APCHING. WITH APPROX 20 SECONDS REMAINING TO GND IMPACT, THE AREA TO THE R VISUALLY AND TCASII CLR, I INSTRUCTED THE PF TO TURN R IMMEDIATELY (WHICH HE DID). THERE WERE NO BREAKS IN THE FREQ TO CONTACT ATC SOME 2 MINS PRIOR TO OUR TURN, AND I USED THE IDENT BUTTON CONTINUOUSLY IN THE LAST 60 SECONDS BEFORE OUR TURN TO ATTEMPT TO GET ATC'S ATTN. DURING ATC'S XMISSIONS 15 SECONDS PRIOR TO OUR TURN, I COULD DISTINCTLY HEAR AN ALARM IN THE BACKGND. I AM CERTAIN THIS WAS EITHER A GND PROX ALARM OR A TA ALARM, ALTHOUGH I CANNOT CLAIM THAT IT WAS SPECIFIC TO OUR ACFT. 20-30 SECONDS AFTER THE TURN, I WAS ABLE TO BREAK INTO THE FREQ AND INFORMED ATC WE WERE NO LONGER ON HIS VECTOR 'TOWARD THE MOUNTAINS,' THAT THE ARPT (BERMUDA DUNES) WAS IN SIGHT AND WE WERE CANCELING IFR, AND WOULD PROCEED TO THE ARPT VFR. HIS RESPONSE, 'RPT CANCELING ON THIS FREQ OR VIA PHONE AFTER LNDG.' I REAFFIRMED OUR CANCELLATION AND WE LANDED WITHOUT FURTHER INCIDENT AT XP04. IT IS CLR THAT THE CTLR LOST SITUATIONAL AWARENESS IN SEPARATION AND SEQUENCING OF IFR TARGETS UNDER THE TFC LOAD. HIS RESPONSE INDICATES THAT HE FORGOT ABOUT OUR TARGET AND IT TOOK A MOMENT FOR HIM TO PROCESS ANY INFO ABOUT US. ALTHOUGH WE DID NOT WISH TO CREATE ADDITIONAL CONFLICTS BY ACTING CONTRARY TO OUR CLRNC (ASSIGNED HDG), IT BECAME CLR THAT UNLESS WE ACTED QUICKLY, THAT THE CTLR WAS NOT GOING TO PROVIDE AN AMENDED CLRNC. CONTRIBUTING FACTORS WERE THE CLR WX IN THE VALLEY PROMPTING MANY PLTS TO FLY THIS DAY. I SEE 2 POSSIBLE WAYS TO HAVE AVOIDED THIS INCIDENT: 1) CANCEL IFR FARTHER OUT. THIS ALLOWS THE PLT TO MANEUVER FOR THE ARPT, AND IF VFR TA'S ARE REQUESTED, THEY CAN BE PROVIDED WITHOUT THE CONSTRUCTIONS OF HAVING TO FOLLOW A CLRNC. 2) LIMIT CTLR WORKLOAD. EACH CTLR MUST DETERMINE A LEVEL FOR WHICH HE OR SHE IS COMFORTABLE WORKING. IF THE IFR TFC CAN'T BE HANDLED PROPERLY, THEN OBVIOUSLY NO ADDITIONAL VFR TFC SHOULD BE ACCEPTED FOR ADVISORIES. SUPERVISION IS A MUST TO ENSURE THAT IF THE SECTOR GETS BUSY SUDDENLY THAT THE CTLR DOES NOT GET OVERLOADED TOO QUICKLY. I DO NOT THINK THAT THIS CASE WOULD HAVE HAPPENED UNDER IFR CONDITIONS FOR 2 REASONS: 1) THE NUMBER OF ACFT WOULD HAVE BEEN GREATLY REDUCED. 2) OUR ROUTING WOULD HAVE TAKEN US S, IN THE VALLEY TO THE THERMAL VOR AND REVERSED COURSE FOR THE VOR APCH INTO BERMUDA DUNES. AS A RESULT OF MAINTAINING IFR RTES AND ALTS, TERRAIN SEPARATION WOULD HAVE BEEN PROVIDED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR CALLED PSP TWR A FEW DAYS AFTER THE INCIDENT AND TALKED WITH A SUPVR. AS IT TURNED OUT, THIS SUPVR HAD BEEN MONITORING IN THE TRACAB AND OBSERVED THE INCIDENT. THE RPTR STATED THAT THE SUPVR 'PULLED' THE CTLR AND TRAINEE OFF THE CTL POS WITH THE RESPECTIVE TAPE. NEITHER THE INSTRUCTOR NOT THE TRAINEE HAD REMEMBERED THAT A DSCNT CLRNC HAD BEEN ISSUED AND ACKNOWLEDGED BY THE HS25 FLC. BOTH CTLRS BECAME DISTR WITH VFR TFC CALLS. THE SUPVR ADVISED THE RPTR THAT HE HAD INITIATED A FACILITY REVIEW OF INSTRUCTOR TRAINING REQUIREMENTS. SINCE PSP WAS A TRAINING FACILITY, AND THEY PRESENTLY HAD 'A LOT OF TRAINEES,' HE ALSO INITIATED A REVIEW OF INSTRUCTOR/TRAINEE SCHEDULING AND QUALIFICATIONS. THE RPTR STATED THAT HE THOUGHT THE INCIDENT WAS REVIEWED IN SUFFICIENT DETAIL BY THE PSP SUPVR THAT HE FELT THE INCIDENT CLOSED. THE RPTR BRIEFED HIS COMPANY CHIEF PLT.

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.