Aviation Accident Summaries

Aviation Accident Summary LAX03FA072

San Jose, CA, USA

Aircraft #1

N893MK

Cirrus Design Corp. SR 20

Analysis

The airplane collided with high-tension power lines in a mountainous area after deviating from the GPS approach procedure in instrument conditions. The airplane was equipped with a GPS navigation system incorporating a moving map feature. During the initial portions of the flight after departure, the TRACON sector controller working the flight initially believed the airplane was destined to another airport and issued a clearance accordingly, but corrected the clearance after the pilot questioned the controller. Shortly after this discussion, the pilot significantly deviated from his cleared course for unknown reasons in the general direction of the mistaken airport. The controller noticed the deviation and corrected the pilot's course. A second controller in the next sector the airplane would be worked by overheard the course correction, and inferred the pilot was somewhat confused. After handoff by the first controller, the second sector controller attempted to provide what he believed was a helpful method of handling the airplane in the transition to the GPS approach; however, these methods of clearing the pilot for the GPS approach were not in strict accordance with FAA Order 7110.65, and included an intercept angle with the final approach course that was greater than allowed. The airplane was on a modified downwind and proceeding to the initial approach fix (IAF) when the controller cleared the pilot to turn toward an intermediate fix between the IAF and the final approach fix (FAF) with the idea in mind that this course would be the same as a radar vector to the FAF. The pilot questioned the clearance, and then acknowledged it, and the airplane turned left toward the FAF, which was directly behind the airplane. The controller noticed that the left turn put the airplane heading toward high terrain and advised the pilot to turn right to go to the intermediate fix. After some additional confusion the airplane's track stabilized on the approach course after passing the intermediate fix. As the airplane passed the FAF the controller told the pilot to contact the tower, but gave him the frequency for the wrong airport. The pilot questioned the controller, who insisted the frequency was correct. The pilot then contacted the second airport tower and was told he was on the wrong frequency. Almost 1 minute elapsed between the pilot's acknowledgement of the erroneous frequency, and his initial contact to the correct tower. During this period the airplane's heading diverged approximately 90 degrees from the published final approach course toward rising terrain and the accident site. The Minimum Safe Altitude Warning alarms went off in the TRACON and in the tower, and the tower controller provided a low altitude safety alert based on the alarm by saying "check your altitude immediately;" however, at the time of the low altitude alert, the airplane was about 500 feet above the Minimum Descent Altitude (the accident site elevation was about 200 feet above the MDA.) and the alert was activated not because the airplane's altitude was below the segment minimums but due to the course and altitude being projected to come in contact with terrain in the near future. This may have confused the pilot and decreased the perceived urgency. The limitations of the radar display effectively masked the initial portions of the course deviation and the controller did not see the deviation for some 30 seconds; however, the controller did advise the pilot that he was off course as soon as he was aware of it. The pilot's unintelligible response was about the time the radar target return went into coast mode.

Factual Information

HISTORY OF FLIGHT On January 23, 2002, at 1653, Pacific standard time, a Cirrus SR 20, N893MK, collided with power lines near San Jose, California. The private pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The airplane was destroyed. The pilot, the sole occupant, sustained fatal injuries. The personal cross-country flight departed Napa County Airport (APC), Napa, California, at 1600, en route to Reid-Hillview Airport of Santa Clara County (RHV), San Jose. Day instrument meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan had been filed. The primary wreckage was located at 37 degrees 16 minutes north latitude and 121 degrees 43 minutes west longitude. During the investigation, the recorded voice channels from the Federal Aviation Administration (FAA) Northern California Terminal Radar Approach Control (NCT), Palo Alto ATCT, and Reid-Hillview ATCT were examined. Recorded radar data from the NCT ARTSIIIA system was also reviewed. During the initial portions of the flight after takeoff from Napa, ATC issued numerous radar vectors and altitude assignments to the pilot for traffic avoidance purposes. Review of the radar data disclosed that the pilot complied with all instructions. At 1627, when the airplane was approximately abeam Oakland International Airport, the NCT Saratoga sector controller instructed the pilot to proceed to navigational fixes near Palo Alto airport (PAO). The pilot questioned the clearance, and in the subsequent exchanges the controller acknowledged his mistaken belief that the pilot was destined to PAO and that the flight was actually destined to RHV. The controller asked the pilot from which fix he would like to initiate the approach, and the pilot requested vectors to the approach "around OZNUM." OZNUM is the Final Approach Fix (FAF) on the RHV GPS 31R procedure. The controller issued a clearance direct to OZNUM. After this exchange, radar indicated the airplane turned almost 90 degrees to the right, and tracked on a course consistent with proceeding direct to PAO. The controller noticed the course deviation, and queried the pilot. The controller provided no specific headings, but told the pilot to make a right turn to avoid traffic associated with San Jose International Airport, and to proceed to OZNUM, which he said was "on the east side of RHV." The pilot acknowledged and made a right turn of approximately 270 degrees, briefly tracking on an approximately southbound course, which did not appear to be aligned with any relevant navigational fix. After approximately 3 miles on that course, the pilot turned left to a track consistent with proceeding direct to OZNUM. The radar data showed that this ground track resulted in the airplane flying overhead RHV, on approximately the reciprocal of the final approach course, i.e., aligned with RHV, and the fixes OZNUM, then ECYON. In his interview, the first NCT LICKE sector controller (L1) said he became aware of N893MK when he overheard the Saratoga sector controller correcting the pilot's course to OZNUM. The L1 controller said he believed the pilot required extra attention and intended to provide what assistance he could. Comparing the voice transcripts to the recorded radar data showed that upon the pilot's initial contact with the LICKE sector, the airplane had passed OZNUM, and begun a slight left turn to the east. At this point the pilot had no further clearance to follow, since the Saratoga controller had cleared him direct to OZNUM with the expectation that L1 would provide vector service. L1's initial instruction was for the pilot to proceed direct to ECYON; the pilot's response was to question the fix. According to L1's statements, he recalled that the airplane was in a position coincident with a downwind leg, and the turn toward ECYON would work out to be the same as a vector to final. Recorded radar data indicates the airplane was flying a course approximately aligned with the Initial Approach Fix (IAF) ZUXOX. Shortly after this exchange, L1 noted the airplane appeared to begin a left turn towards OZNUM, but he instructed the pilot to turn right toward ECYON in order to remain clear of a higher terrain area. At this time, OZNUM was directly behind the airplane, and ECYON at about the four o'clock position. The pilot completed a right turn, briefly flying a course consistent with tracking towards OZNUM, then made a slight left turn and flew a course consistent with the published segment between ZUXOX and ECYON. L1 said he observed the pilot on this course and issued clearance for the approach. FAA Order 7110.65 specified that Standard Instrument Approach Procedures "shall commence at an Initial Approach Fix or an Intermediate Approach Fix if there is not an Initial Approach Fix. Where adequate radar coverage exists, radar facilities may vector aircraft to the final approach course [by assigning] headings that will permit final approach course interception on a track that does not exceed 30 degrees." The order further states that vectors should be issued if required to intercept the final approach course. ECYON was not an IAF. Review of the radar derived ground track revealed that the intercept angle was about 40 degrees. While the flight was progressing between ECYON and OZNUM, a controller change occurred at LICKE sector. L1 advised the second controller (L2) that N893MK was on the approach and the only remaining task was to issue frequency change to RHV tower. As the airplane passed just northwest of OZNUM, L2 instructed the pilot to contact the tower on frequency "118.6." This frequency is actually assigned to PAO tower. The pilot queried the controller if that was actually correct. The controller insisted, "Yes sir, it is." The pilot complied and contacted PAO tower. The pilot and the PAO controller discussed that he was on the wrong frequency and the pilot said he would switch to the RHV frequency of 119.8. During this conversation, radar indicated the airplane began a turn to the right, with the first target visibly displaced from the final approach course at 1652:33, approximately over JOPAN waypoint. At 1652:50, the pilot reported to RHV tower "descending from JOPAN two thousand feet five point four miles from missed approach point." Radar data agreed with the pilot's report; however, the course had diverged almost 90 degrees from the final approach course. Within 2 seconds of the pilot making initial contact with RHV tower, the ARTS Minimum Safe Altitude Warning System (MSAW, see ATC Group factual report in docket material) provided a visual and audible alert at the RHV tower and NCT. In response to the pilot's call, the RHV tower controller cleared the pilot to land then said "low altitude alert, check your altitude immediately." The MSAW system activates whenever the targets projected track will encounter higher terrain, or, when the mode C reported altitude is below the minimum safe altitude for the navigational segment being flown. Based on the radar data, the airplane's projected track was diverging away from the centerline of the approach, and toward higher terrain. At the time of the alert the airplane was at about 1,900 feet, and the minimum altitude for the final segment is 1,440 feet. About 30 seconds later, the tower controller notified the pilot that he appeared off course. The pilot made a brief unintelligible transmission and no further radio or transponder signals were received. The radar track of the airplane was lost in the area of high-tension power lines, located 6.7 miles south east of RHV at an altitude of 1,600 feet mean sea level (msl). The last radar data with an altitude return was at 16:53:40, and showed the airplane at a mode C reported altitude of 1,700 feet. PERSONNEL INFORMATION A review of FAA airman records revealed the pilot held a private pilot certificate with an airplane single engine land and instrument airplane rating. The pilot was issued a third-class medical on June 8, 2001, with the limitations the pilot must wear lenses for distant vision, and possess glasses for near vision. An examination of the pilot's logbook indicated a total flight time of 460.7 hours, of those 362.4 hours were dual received. The pilot had logged his total IFR time as 150.3 hours of which 10.7 hours were actual IFR. He had 334 hours in this make and model; 84.8 hours were logged in the last 90 days. The pilot had completed and passed an instrument airplane check ride on January 6, 2003. The designated examiner (DE) was interviewed and related the pilot was very detail orientated, and also very knowledgeable about the Cirrus SR 20. AIRCRAFT INFORMATION The airplane was a Cirrus SR 20, serial number 1038. A review of the airplane's logbooks disclosed the annual inspection was completed on February 20, 2002. Total airframe time was listed as 67.8 hours and a Hobbs time of 67.8 hours. The airplane had a total time of 369.3 hours. The transponder and altimeter/static and altitude reporting systems were inspected on February 20, 2002. A Teledyne Continental Motors IO-360ES-6B engine, serial number 357190, was installed in the airframe in May 2000. The engine had a total time of 369.3 hours. An aircraft weight and balance report dated February 18, 2002, revised the airplane's weight and balance data sheet. It listed the new empty weight as 2121.23 pounds; total moment of 296507.35-inch pounds, and listed the empty center of gravity as 139.78 inches aft of the datum. The Cirrus SR 20 uses conventional flight controls for ailerons, elevator, and rudder. The control surfaces are pilot controlled through either of two single-handed side control sticks mounted on each side of the airplane's cockpit. The neutral position of the left side stick is at a 45-degree angle to the right. The neutral position of the right side stick is a 45-degree angle to the left. The accident airplane was being flown from the left pilot seat. A pilot flying from the left seat would rest his left-hand on the side control stick; any inadvertent pressure applied by the pilot could potentially induce an unintentional right turn of the airplane. The accident airplane (SN 1038) was originally equipped with the factory "Avionics Configuration C" package which included dual Garmin GNS 430's. The GNS 430 is a combination global positioning satellite (GPS) receiver, communication, and navigation system. The GNS 430's were mounted in the center console of the airplane below the ARNAV ICDS 2000 display. A major repair and alteration (FAA Form 337) dated February 20, 2002, was filed reporting an upgrade in the avionics, which were installed in the airplane. The transponder was upgraded; a Ryan 9900BX traffic collision avoidance detection (TCAD) system; and a WX-500 stormscope system were installed. AIRPORT, NAVIGATION FACILITIES AND APPROACH INFORMATION The Airport/ Facility Directory, Southwest U. S., indicated RHV runway 31R was 3,101 feet long and 75 feet wide. The runway surface was asphalt. The only IFR approach into RHV is the GPS RWY 31R. According to a review of facility records, all relevant ATC and navigational equipment was operating. There were no NOTAMs or other evidence of any GPS anomalies in the vicinity of RHV. The GPS 31R approach procedure was a fairly new procedure, prior to the establishment of this approach, RHV did not have any Standard Instrument Approach Procedures. During interviews with the controllers at NCT and RHV they reported that they had been briefed on the approach procedure, and were generally familiar with it, although it did not receive heavy use. The RHV GPS 31R approach course was established in a congested area of high traffic density associated with the airports in the southern San Francisco Bay area. The final approach course closely paralleled the SJC approach course to the southwest, such that airplanes established on these approaches were separated by the minimum allowed lateral distance. To the northeast, terrain rose rapidly, leaving very little room to maneuver for airplanes below 4,000 feet. Review of the radar display terminals at NCT disclosed that video mapping did not directly depict the GPS 31R final approach course. In order to visualize the course, controllers had to visualize a line between the airport symbol, and the OZNUM and ECYON waypoint symbols. The RHV Tower Remote ARTS Color Display (R-ACD) video map did include a depiction of the final approach course as a series of dashed lines. Depictions of JOPAN and OZNUM waypoints also appeared on the map. In their interviews, the controllers noted the waypoint symbols are quite large; the investigators observed that the "points" on the symbols extended approximately 0.75 miles beyond the centerline of the approach course. ARTS radar targets on the controllers display were oriented such that the longer dimension of the return was aligned perpendicular to the azimuth from the radar site, (i.e. "broadside") and a target whose track is diverging from the final approach course would not be readily apparent. This topic is discussed in detail in the ATC Group Factual Report, which is contained in the docket for this accident. METEOROLOGICAL INFORMATION The closest official weather observation station was Reid-Hillview Airport of Santa Clara County (RHV), San Jose, located 6.7 nautical miles (nm) northwest of the accident site. The elevation of the weather observation station was 133 feet msl. A special aviation weather report (METAR) for RVH was issued at 1653. It stated: skies 1,200 feet broken, 8,000 feet overcast; visibility 4 miles; winds from 280 degrees at 12 knots; temperature 60 degrees Fahrenheit; dew point 59 degrees Fahrenheit; and altimeter 30.24 inHg. WRECKAGE AND IMPACT The terrain at the accident site was mountainous. The airplane came to rest approximately 650 feet on a bearing of 032 degrees from the first identified point of contact (IPC). The accident site was at the bottom of a ravine. The airplane came to rest on a magnetic heading of 056 degrees at an almost level attitude on the upslope side of a 45-degree slope. The first identified point of contact (IPC) was the west side static line approximately 100 feet south of the Pacific Gas and Electric (PG&E) high-tension power line tower number 130. The second identified point of contact was the pair of 500 KV power lines located on the east side of the PG&E tower number 130. One of the power lines was lying on the ground adjacent to tower number 130; it had pieces of fiberglass imbedded in a broken bracket, which is used to suspend the power lines from the tower. Approximately 6 feet north of the broken bracket were witness marks on the wire that appeared to be at a 45-degree cut into the power line. The power lines are approximately 2 inches across. All of the airplane's flight control surfaces were at the accident site. The rudder, elevators, and horizontal stabilizer assemblies were attached to the empennage. All control surfaces and their associated mass balance weights were in the debris field. The outboard section of the left wing was in a tree approximately 160 feet northeast of the IPC. The left wing section displayed charring. On the left wing section approximately 3 feet inboard from the wing tip, there was a semicircular depression approximately 2 inches across. The airplane was equipped with an emergency ballistic parachute system. The ballistic parachute system had not been deployed. The safety pin, which is used to prevent inadvertent deployment, was still in place. The safety pin had a tag attached to it that is red in color with white lettering and read, "SAFETY PIN REMOVE BEFORE FLIGHT." MEDICAL AND PATHOLOGICAL INFORMATION The Santa Clara County Coroner completed an autopsy. The FAA Toxicology and Accident Research Laboratory performed toxicological testing of specimens of the pilot. The results of analysis of the specimens were negative for carbon monoxide, cyanide, and volatiles. Results for tested drugs were; 0.015(ug/ml, ug/g) Dextromethorphan detected in blood, Dextromethorphan present in urine, Dextrorphan detected in blood, Dextrorphan

Probable Cause and Findings

The pilot's failure to maintain the course for the published approach procedure due to his diverted attention. The distraction responsible for the pilot's diverted attention was the erroneous frequency assignment provided by ATC and the resultant task overload induced by this problem and the confusion surrounding the ATC clearances to get established on the final approach course, which likely involved repeated reprogramming of the navigation system. Factors in the accident include the failure of ATC to provide the pilot with a timely and effective safety alert concerning the deviation from the proper course, which was influenced in part by the features of the radar display at both facilities which made the deviation more difficult to detect, and the nature of radar as a secondary tool for a VFR tower controller. An additional factor was the nonstandard method of providing approach clearance, which likely may have exacerbated pilot task overload.

 

Source: NTSB Aviation Accident Database

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