N299EH

HISTORY OF FLIGHT

On October 10, 1996, about 0447 central daylight time, a Mbb BO-105 CBS-4 twin-engine helicopter, N299EH, owned and operated by ERA Aviation Inc., of Lake Charles, Louisiana, was destroyed after impacting brackish coastal marshland near Cameron, Louisiana. The airline transport rated pilot, who was the sole occupant, was fatally injured. Dark night visual meteorological conditions prevailed during the 14 Code of Federal Regulations Part 91 positioning flight. The flight originated from the company's Cameron helicopter base at 0443, and was en route to the company's main base at Lake Charles, Louisiana. At 0446, the pilot filed a company flight plan via radio.

According to company flight following records, the helicopter departed the Cameron field base at 0443 to reposition the aircraft to the Lake Charles base for maintenance (transmission replacement due to chip lights). Company flight following personnel reported that no radio/distress calls were received from the helicopter.

According to the operator, the following was the known chronology of events leading to the accident flight:

1730 (October 9th) The pilot reported for duty at the Lake Charles Base after being off duty for 12 days.

1900 (October 9th) Maintenance inspection performed (transmission) by Cameron Base personnel on N299EH.

2200 (October 9th) The pilot worked on a weight and balance report for N299EH.

2305 (October 9th) The pilot performed a maintenance ground run-up on N298EH.

2315 (October 9th) The pilot and other Lake Charles Base pilots were inside awaiting assignments.

0307 (October 10th) The pilot departed Lake Charles Base in N298EH on a repositioning flight to the Cameron Base to replace N299EH.

0323 The pilot arrived at Cameron Base in N298EH.

0332 The pilot performed a ground run-up on N299EH to leak-check the transmission. The ground run-up was reported "OK."

0343 Cameron Base maintenance personnel performed a final inspection on N299EH.

0443 The pilot departed Cameron Base in N299EH en route to Lake Charles Base.

0446 The pilot called his flight plan in to Lake Charles, reporting "ETA 0505, solo, one-hour fuel."

O505 No radio contact from N299EH. Company initiated a ramp search and commenced company search and rescue plan.

0703 Search aircraft, N167EH, located the wreckage of N299EH in the marsh, approximately 4 nautical miles on a magnetic bearing of 028 degrees from Cameron Base. GPS coordinates: North 29 degrees 50 minutes 33.5 seconds, West 93 degrees 15 minutes 08.2 seconds (bearing 199 degrees from Lake Charles VOR at 19.5 nautical miles).

PERSONNEL INFORMATION

The pilot held a Rotorcraft-Helicopter Airline Transport Pilot Certificate for BH-206, BH-212, and BO-105 type helicopters, with commercial ratings in Single and Multi-Engine Land, Instrument Airplane, and CFI Rotorcraft-Helicopter. His current Class I FAA medical certificate, dated July 1, 1996, had a limitation for eyeglasses to be worn for near vision correction. He was employed with ERA since January 8, 1981. His total accumulated flight time was 11,897 hours, of which 2,053 hours were flown in the BO-105 helicopter. His total accumulated night helicopter time was 316 hours, of which 28 hours were flown in the 90 days prior to the accident. The pilot's total instrument time was 446 hours, of which 142 hours were flown in actual instrument conditions. His total flight time experience in Gulf of Mexico flight operations was over 6,700 hours. Additionally, he had been a FAA designated company check airman since 1984.

According to company records, the pilot's last annual re-qualification in the BO-105 was satisfactorily demonstrated on June 13, 1996.

At the request of the NTSB investigator-in-charge, the operator's Director of Safety collected human factor issues/information that he retrieved from friends, family members, and work associates of the pilot during the course of the investigation. He listed them categorically in a written report. Excepts of the report are listed below:

Fatigue and Circadian Rhythm - The pilot had been on vacation for two weeks from September 26 to October 8, and spent that time with his family and friends in Arizona. During the vacation, the pilot was on a normal day/night sleep cycle and was sleeping about 9-10 hours per night. On the day prior to the accident, the pilot awoke in the morning when his wife went to work. According to his wife, he took a nap for about 2 hours during the day and called her at work when he awoke. The pilot did not sleep during the night prior to the accident, apparently due to the workload in helping base maintenance personnel with aircraft run-ups. According to personnel who worked with the pilot, he normally tried to get some sleep during the night shift. The accident flight was conducted during the 11th and 12th hours of the pilot's 12-hour night shift.

Situational Awareness - The pilot's co-pilot for the Bell 412 standby aircraft stated that the pilot was "very good" at night flying, always followed the checklist and briefed on what he was preparing to do. Another pilot interviewed stated that he had to take the controls from the pilot several years ago because the pilot was descending too low during an approach to an offshore platform. According to the operator, it would be a normal reaction by a helicopter pilot during daylight hours to fly lower than normal altitude if he suspected, or was concerned about a possible mechanical problem. According to the operator, a typical normal altitude for this flight would have been about 1,000-1,500 feet AGL. The pilot may have elected to remain at a lower than normal altitude in the event the transmission (which was recently worked on) developed a problem. This would allow the pilot to get the aircraft on the ground sooner if necessary, but would also allow for less time for the pilot to notice a slow, undetected descent.

Night Visual Effects - The helicopter was parked on a pad near an overhead, high intensity yard light. While waiting for the transmission maintenance to be completed, the pilot was in the base office. Upon the completion of maintenance, the pilot went directly from the lighted office to the lighted parking pad, performed a pre-flight, and departed. The average pilot requires about 30-45 minutes in a reduced light or dark environment for effective "dark adaptation" prior to dark night flying. According to the operator, if the pilot had elected to remain at a lower than normal altitude, he may have had some difficulty in correctly determining his altitude above an area that had little or no ground lights and a vast expanse of swamp and marsh along the flight path from Cameron to Lake Charles. Additionally, altitude and sink rates can be difficult to judge during dark night flights conducted over unlighted terrain when the lights of a city (Lake Charles) are in the distance ("Black Hole Effect"). According to the operator, this is especially true in the BO-105 helicopter, as slow descents and climbs are typically not "felt" by the pilot.

AIRCRAFT INFORMATION

The 1989 model MBB BO-105 CBS-4 helicopter, serial number S-807, had an airframe total time since new (TTSN) of 4,545.8 hours. The helicopter was equipped with two Allison 250-C20B turbo-shaft engines. Engine #1 had 4,254.5 hours total time since new, and 2,164.1 hours since its last major overhaul. Engine #2 had 9,567.5 hours total time since new, and 2,164.1 hours since its last major overhaul. The helicopter did not have a radar altimeter or GPWS installed.

The helicopter was being maintained in accordance with the ERA Approved Aircraft Inspection Program (AAIP). The program contains a Daily Service Check (DSC), a 50-hour Preventative Maintenance Inspection (PMI), a series of 5 separate phase inspections conducted 150 hours apart, a 2,500 hour major airframe inspection, and "additional" maintenance items that are stand alone inspections. The descriptions and details of the inspection program are contained in the ERA maintenance manual, which is FAA approved.

A detailed review of the aircraft's maintenance records indicated that all of the inspections required by the AAIP had been performed. Airworthiness Directive (AD) compliance was verified through maintenance record review and visual inspection of the applicable items on the aircraft (during wreckage examination). Compliance with all pertinent AD's was verified. Further review of the maintenance records did not reveal evidence of any uncorrected defects or anomalies. The following is a chronology of the most recent maintenance performed prior to the accident:

October 10, 1996 - Removal of the left and right transmission input pinions for transmission service and inspection for transmission chip light occurrences.

October 8, 1996 - Scheduled "A" check in accordance with the AAIP. No uncorrected defects found, and returned to service.

July 20, 1996 - Hydraulic unit switch-over check performed in compliance with FAA Airworthiness Directive (AD) 96-08-04. No uncorrected defects found, and returned to service.

METEOROLOGICAL INFORMATION

Lake Charles base, located about 19 miles north of the accident site, reported clear skies, winds from 260 degrees at 3 knots, temperature 55 degrees F, dew point 55 degrees F.

Cameron base, located about 4 miles south of the accident site, reported clear skies, winds from 280 degrees at 3 knots, temperature 64 degrees F, dew point 63 degrees F.

Company personnel at the Cameron base reported that it was a "clear, dark night" at the time the helicopter departed the base.

WRECKAGE AND IMPACT INFORMATION

The accident site was located in coastal marshland with dense vegetation laced with shallow inland canals approximately 4 nautical miles north of the Cameron base. The wreckage was found severely fragmented along a 300-foot long energy path bearing about 003 degrees magnetic. The site had a persistent fue...