N115AL

HISTORY OF FLIGHTS

On June 1, 1997, approximately 1125 central daylight time, a midair collision occurred between N115AL, a Bell 206B helicopter, registered to and operated by Offshore Logistics, Inc., doing business as Air Logistics, and N2773A, a Bell 206L-1 helicopter, registered to and operated by Houston Helicopters, Inc., approximately 3 nautical miles west of Intracoastal City, Louisiana. N115AL sustained substantial damage, and N2773A was destroyed. The commercial pilot of N115AL sustained minor injuries, and the commercial pilot of N2773A was fatally injured. There were no passengers in either helicopter. Visual meteorological conditions prevailed for the Title 14 CFR Part 91 positioning flights and company VFR flight plans were filed by both pilots. N115AL departed the Air Logistics Heliport at Intracoastal City and was en route to Grand Chenier, Louisiana. N2773A departed from the Abbeville Municipal Airport in Abbeville, Louisiana, and was en route to an offshore oil platform in East Cameron Block 109.

During an interview conducted by the NTSB investigator-in-charge (IIC), the pilot of N115AL reported that he departed Intracoastal City at 1120 westbound towards Grand Chenier. He climbed to 700 feet agl, leveled off, set cruise power, and scanned the instruments. The pilot then saw "the nose and left side of a red helicopter" to his right and at a "slightly lower altitude." He rolled his helicopter to the left and was in a "40 to 45 degree" left bank when he felt the impact. The pilot's next recollection was that his helicopter was in a descent on an easterly heading and "shaking violently." His helicopter touched down in the water, rolled over and sank. He was able to free himself from the helicopter and swim to the surface where he was picked up by a man in a boat.

Three witnesses to the collision reported conflicting information concerning the flight paths of the two helicopters. During an interview conducted by the IIC and in a written statement, the witness who picked up the pilot of N115AL reported that he was westbound in his boat in the slough north of the Leland Bowman Lock when he observed a red helicopter (N2773A) overhead and to his right traveling "roughly westbound." The red helicopter "appeared to be climbing slowly." He then noticed a second blue helicopter (N115AL) "slightly north of and slightly higher than the first" helicopter; the blue helicopter was also traveling westbound "but on a course heading that would intersect the red helicopter."

According to the witness, the pilot of the blue helicopter attempted to avoid the collision "by pitching the aircraft up and simultaneously banking to the right very steeply." The witness then observed the main rotor blades of the blue helicopter impact the tail rotor of the red helicopter. The red helicopter's tail rotor shattered "with visible debris and a loud explosion," and the tailboom "folded downward and separated from the fuselage." The red helicopter "pitched over fully inverted" and impacted in the trees on the north bank of the slough.

Following the collision, the witness observed that the blue helicopter had leveled out facing south and "appeared to be translating, or moving sideways," to the right while "yawing to the left." It moved out over the water and descended "rapidly in a controlled manner to land in the water." As the blue helicopter passed his boat, the witness "observed it shuddering violently and small pieces of debris falling off."

Two crewmen on a tugboat that had "just" passed through the Leland Bowman Lock eastbound also witnessed the midair collision and were interviewed by telephone and provided written statements to the IIC. One of the crewmen stated that the red helicopter (N2773A) was westbound and the blue helicopter (N115AL) was eastbound. The other crewman stated that the red helicopter was westbound and the blue helicopter was southbound. Both crewmen reported that immediately prior to the collision, the nose of the blue helicopter went up "like it was trying to stop."

PERSONNEL INFORMATION

The pilot of N115AL held a commercial pilot certificate with helicopter, single and multiengine land airplane, and instrument ratings. He successfully completed the competency check required by Title 14 CFR Part 135.293(b) in a Bell 206L-1 helicopter on April 14, 1997. According to FAA records, he held a first class medical certificate dated July 18, 1996, with the restriction, "must wear corrective lenses." The pilot reported that he was wearing prescription sunglasses at the time of the collision. He had a total flight time of 2,345 hours of which 1,395 hours were in helicopters.

The pilot of N2773A held a commercial pilot certificate with helicopter, single and multiengine land airplane, and instrument ratings. He successfully completed the competency check required by Part 135.293(b) in a Bell 206B helicopter on February 20, 1997. According to FAA records, he held a first class medical certificate dated March 3, 1997, with the restriction, "must wear corrective lenses." It could not be determined if the pilot was wearing his glasses at the time of the collision. He had a total flight time of approximately 11,000 hours.

AIRCRAFT INFORMATION

N115AL, a Bell 206B, was manufactured in April of 1978. At the time of the accident, the helicopter had accumulated 18,943 hours of flight time. It was painted blue with white trim markings and had an anti-collision light installed on the top of the vertical fin and two landing lights, one facing down and one facing forward, installed in the nose. During examination of the wreckage, the switch for the anti-collision light was found in the "ON" position, and the switch for the landing lights was found in the "BOTH" position.

N2773A, a Bell 206L-1, was manufactured in August of 1979. At the time of the accident, the helicopter had accumulated 7,310 hours of flight time. It was painted red with white and black trim markings and had an anti-collision light installed on the top of the vertical fin and two landing lights, one facing down and one facing forward, installed in the nose. During examination of the wreckage, the light switch positions could not be determined due to the extent of impact damage.

METEROLOGICAL INFORMATION

At 1150, the reported weather conditions at Intracoastal City were wind from 330 degrees at 5 knots, visibility 7 statute miles, scattered clouds at 4,000 feet, temperature 77 degrees Fahrenheit, dewpoint 57 degrees Fahrenheit, and altimeter setting 29.90 inches of Hg.

At the time of the accident, the position of the sun at Abbeville, Louisiana, located approximately 12 nautical miles north northeast of the accident site, was 103 degrees (true) in azimuth and 66 degrees in elevation.

COMMUNICATIONS

During examination of the wreckage of N115AL, the digital display of the single communications radio, a King KY-196A, precluded determination of the frequency selected. Review of Air Logistics's radio log for June 1, 1997, indicated that the pilot of N115AL reported departing Intracoastal City en route to Grand Chenier at 1118.

Examination of the wreckage of N2773A revealed that the helicopter's single communications radio, a King KX170B, was tuned to a frequency of 129.45. The Director of Operations of Houston Helicopters stated that 129.45 was a company frequency used for flight following. A review of Houston Helicopters's radio log for June 1, 1997, indicated that the pilot of N2773A reported departing Abbeville en route to East Cameron 109 at 1119.

The accident occurred approximately 3 nautical miles west of the Petroleum Helicopters Heliport in Intracoastal City. Petroleum Helicopters (PHI) operates a radio base station at this heliport with a frequency of 122.85. The station provides local (within 10 nautical miles of the heliport) traffic advisories to participating VFR aircraft.

According to information provided by PHI, the Intracoastal City traffic advisory area is one of eleven such advisory areas established at onshore high density helicopter traffic locations around the Gulf of Mexico by the Helicopter Safety Advisory Conference (HSAC). HSAC was formed in 1978 "to promote safe procedures in the operation of rotary-winged aircraft," and its voting membership is comprised of companies that have "direct operating involvement in helicopter operations in the Gulf of Mexico." The HSAC recommended practice for operations in the Intracoastal City area states, in part:

Outbound traffic will:

a. When departing a heliport within the 5 NM circle will call prior to taking off, and wait a few seconds for the traffic advisory (or another aircraft) to respond with any conflicting traffic, before beginning a takeoff.

b. Execute an expeditious climb between 700 ft. and 1000 ft. after takeoff.

c. Maintain 700 ft. to 1000 ft. until 5 NM from the Reference Point [PHI heliport].

d. Climb to desired cruise altitude after reaching 5 NM from the Reference Point.

e. Call "Clear of the area" 10 NM from the Reference Point including altitude.

Local Traffic:

Traffic passing through the traffic advisory area will do so at 1200 ft. or above. Between the altitudes of 1200 and 3000 ft., pilots will:

a. Call at 10 NM from the Reference Point, giving altitude and route of flight as they enter the area.

b. Call "Clear of the area" at 10 NM from the Reference Point as they leave the area.

The landing light will be ON during operations within 10 NM of the Reference Point.

Do not overfly any heliport below 500 ft.

On the NOAA U.S. Gulf Coast VFR Aeronautical Chart issued on November 7, 1996, and valid on the date of the accident, the area within 10 nautical miles of Intracoastal City was identified with blue shading as a High Density Helicopter Activity Area, and 122.85 was listed as the radio frequency for this area. On the NOAA Houston Sectional Aeronautical Chart issu...