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NTSB investigation record

LAX00MA273

Completed

Aerospatiale As355F1· N510TG

Date
July 21, 2000
Location
Kahului, Maui, HI
Conditions
IMC
Record
Published September 16, 2021

Primary finding

Probable cause

The pilot's inadequate decision by which he continued visual flight rules flight into instrument meteorological conditions. Also causal was his failure to maintain terrain clearance resulting in a collision with mountainous terrain. A contributing factor was the low ceiling.

Investigator assessment

Analysis narrative

While operating under visual flight rules during an on-demand aerial sightseeing tour flight, the non-instrument-rated helicopter pilot encountered instrument meteorological conditions and impacted the 45- to 60-degree up sloping face of a 2,900-foot-high mountain, about 50 feet below the peak. The tour was intended to circumnavigate the west Maui Mountains with occasional close-up views of majestic locations. About 45 minutes before the accident, while returning from another tour flight, the pilot had flown near the accident site area. A videotape made during the earlier flight indicated that clouds were approaching the transition route into the valley, and the pilot elected to bypass it as did other tour pilots due to the clouds obscuring the mountain peaks in the Iao Valley. According to other company pilots, the weather conditions were typical for the area and included the tendency for rapidly changing conditions. When the search had begun for the overdue tour flight, the search pilots were unable to proceed up the valley due to the low height of the clouds. A witness in the Iao Valley State Park indicated that about 1000, he observed the Iao Needle (a vertical rock spire rising from the valley floor). The witness stated he noticed that a solid ceiling of clouds stretched from one side of the valley to the other (north to south). The cloud base obscured the upper 1/4 to 1/3 of the needle. (The Iao Needle's elevation at the top is about 2,250 feet msl, and it is located about 2 miles east of the accident site.) Three other tour flights were conducted within 2 miles of the accident site between 0950 and 1031. According to the pilots of these flights, the tours were modified to exclude the area flown by the accident pilot because of the weather conditions they observed in the area. Specifically, clouds obscured the Iao Valley ridgelines. Based on recorded radar data, about 10 minutes before completing the planned 30-minute-long tour, the pilot attempted to transition from the leeward to the windward side of the island via an established route into the Iao Valley. The pilot entered an area having multiple layers of clouds while climbing northward from 3,400 to 3,900 feet. Within 1 minute, the pilot reversed course and attempted to exit the valley. The pilot likely became disoriented regarding his location relative to the previously overflown ridgeline, and while in instrument meteorological conditions descended to 2,850 feet, whereupon the helicopter impacted nearly perpendicular to the face of the mountain.

Source record

Factual narrative

1.1 HISTORY OF FLIGHT On July 21, 2000, about 1020 Hawaiian standard time, an Aerospatiale AS 355F1, N510TG, collided with mountainous terrain while descending in the Iao Valley, about 8.7 nautical miles (nm) miles west-southwest of the Kahului Airport, on the island of Maui, Hawaii. The helicopter was operated by Helicopter Consultants of Maui, Inc., d.b.a. Blue Hawaiian Helicopters. A company visual flight rules (VFR) flight plan was filed for the planned 30-minute-long tour flight that was operated under the provisions of 14 CFR Part 135. Instrument meteorological conditions prevailed in the vicinity of the accident site. The helicopter was destroyed by impact forces and a postimpact ground fire. The commercial pilot and six passengers were fatally injured. The purpose of the flight was to provide the passengers with a sightseeing tour of the northwest portion of the island of Maui. The flight originated from a heliport on the Kahului Airport at 0955. According to management personnel at Blue Hawaiian Helicopters (BHH), the established tour route involved circling mountains located in the western portion of the island. The operator's tour literature advertises that the tour would provide the fare-paying passengers with views of deep valleys, knife-edged ridges, mist-shrouded peaks, waterfalls cascading down towering cliffs, and a rainforest. About 0959, after the pilot's takeoff and departure from the airport vicinity, the Federal Aviation Administration (FAA) local air traffic controller advised the pilot that radar services were terminated. The pilot acknowledged the controller and proceeded flying on the tour. Contrary to instructions, the pilot did not reset the helicopter's transponder from its assigned code to the code for flying under visual flight rules (VFR). There were no further recorded radio transmissions to or from the accident pilot. The majority of the helicopter's flight and altitude tracks were recorded by radar. The National Transportation Safety Board's Vehicle Performance Division performed a "Recorded Radar Study" in which it examined radar data and provided graphs depicting the helicopter's flight route in relation to the surrounding terrain. As evidenced from the radar beacon data, upon departing Kahului, the helicopter proceeded in a counterclockwise direction circumnavigating the western Maui Mountains. Near the completion of the tour flight, the helicopter was cruising in an easterly direction toward the Iao Valley. About 1018:29, while at 3,400 feet (as evidenced by altitude transmissions from the helicopter's Mode C equipped transponder), the helicopter turned northward, flew over a ridgeline and entered the Iao Valley. By about 1019:34, the helicopter had flown approximately 1 mile northward into the valley while climbing to at least 3,900 feet. The radar data further indicates that the helicopter then reversed direction and commenced a descent while proceeding along a southerly course. At 1019:44, the helicopter had descended to 3,600 feet, and at 1019:58, it was at 3,400 feet. The helicopter's last recorded radar position (utilizing beacon target data) occurred at 1020:03. At this time the helicopter had descended to 3,000 feet. By the time of the next radar sweep approximately 5 seconds later, the target had disappeared. The accident site was located about 2,850 feet mean sea level (msl), approximately 1/8 mile southeast of its last recorded radar position. According to BHH's owner, he has an intimate knowledge of the general area where the accident site is located, having flown in or near the vicinity on numerous occasions. The owner indicated that, although alternate routes are available for the accident pilot to have utilized en route back to Kahului, the pilot's choice of transitioning from the Oluwalu valley into the Iao Valley was the "preferred route" as "it is very majestic as well as a more direct" route through the mountains. A search for the overdue helicopter was initiated when it had not returned to the Kahului Airport within 10 minutes of its planned landing time. According to BHH's chief pilot, the air search in the vicinity of the helicopter's last recorded position on radar was initially hampered due to the presence of the low elevation layer of clouds that obscured the mountainsides. The accident site was located approximately 1503, near the southwestern portion of the Iao Valley. 1.2 PERSONNEL INFORMATION 1.2.1 FAA Certificates Held and Flying Experience. The pilot held a commercial pilot certificate with a rotorcraft helicopter rating. He also possessed a certified flight instructor certificate for rotorcraft; however, it expired in 1974. On February 29, 2000, the pilot was issued a second-class aviation medical certificate with the following restrictions: "must wear lenses for distant vision and possess glasses for near vision." On the medical certificate application form the pilot reported that his total pilot time was over 12,500 hours. According to BHH, by the accident date, the pilot's total flight time was approximately 12,650 hours, of which 12,500 hours were as pilot-in-command. All of the pilot's flight time was acquired flying rotorcraft. During the 90- and 30-day periods that preceded the accident, the pilot had flown for 231.4 and 82.0 hours, respectively. The pilot's total flying experience in the accident model of helicopter was 55.8 hours. Also, during the 90- and 30-day periods that preceded the accident, the pilot had flown the accident model of helicopter for 25.6 and 4.9 hours, respectively. No instrument flying experience was recorded during the previous 90-day period. The pilot did not hold an instrument rating. Regarding his instrument flying experience, BHH reported that the pilot's total actual and simulated experience was 1.0 and 4.0 hours, respectively. In 1996 Board documents indicated that the pilot's total actual and simulated experience was 0 and 20 hours, respectively. A review of the pilot's aviation medical records maintained by the FAA indicates that in June 1996, he reported his total civilian pilot time to date was 8,000 hours, and during the past 6 months he had flown 20 hours. In July 1997, his pilot time was reported at 10,000 hours, and during the past 6 months he had flown 150 hours. In February 1998, he also reported his pilot time at 10,000 hours, and he indicated having flown 50 hours during the past 6 months. One year later, in February 1999, the pilot reported his pilot time at 11,500 hours, and indicated he had flown 50 hours during the past 6 months. On the pilot's last medical certificate application form he indicated having over 12,500 hours of flying experience. He indicated that he had flown over 500 hours during the past 6 months. The pilot's personal flight record logbook was not provided to Safety Board investigators for examination. 1.2.2 Preemployment Clearance and Hiring. BHH hired the pilot in April 1999. According to the Pilot Records Improvement Act of 1996, before hiring an applicant as a pilot, air taxi operators must request and receive records from any company who employed the pilot during the past 5 years. The records address such items as the pilot's history of drug and alcohol testing, completion of training due to poor performance, removal from flying status for any performance or professional competency reason, and disciplinary action. The requisite records were not received from Briles Wing & Helicopter, Inc., the company at which the pilot had worked immediately prior to being hired by BHH. BHH's chief pilot reported to the Safety Board investigator that one of its pilots had known the prospective employee for 22 years and was "very familiar" with the applicant's experience. Had BHH an indication that the applicant's background was "unfavorable" he would not have been hired. 1.2.3 Accid

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