History of Flight
On July 17, 2009, about 1510 Pacific daylight time, a Croman SH-3H, registration N613CK, collided with terrain at a heliwell site near the Willow Creek Hellibase, Willow Creek, California. The United States Forest Service (USFS) was operating the helicopter under 14 Code of Federal Regulations Part 137. The USFS had contracted with Croman Corporation for the helicopter. The commercial-rated first pilot, designated as pilot-in-command (PIC), was not injured. The commercial-rated second pilot, designated as second-in-command (SIC), sustained minor injuries. The helicopter rolled onto its side and sustained substantial damage to the main rotor blades, fuselage, and tail rotor. The flight departed the Willow Creek helibase about 1416 on a fire fighting mission. Visual meteorological conditions prevailed, and a company flight plan was filed.
The contractor reported that the helicopter used a snorkel system to fill an internal tank from a heliwell (a 5,000-gallon portable tank). The crew had completed four circuits; the accident occurred on the fifth. On the third trip, the PIC jettisoned some water to reduce gross weight for transitioning to forward flight.
On the accident flight, the PIC was at the controls, flying from the left seat. He approached the heliwell from the south as he had on previous trips. As he lowered the snorkel into the heliwell, he made a right pedal turn to a southerly heading for egress. The PIC stated the helicopter took on 400 to 450 gallons of water. As he applied power to climb, the SIC called out "droop" several times. The PIC stopped applying power and moved forward. The SIC called out 98 percent rotor rpm (Nr). After the PIC reduced collective slightly to gain Nr, the SIC again called out droop. The PIC stated Nr fell possibly to 92 percent. He tried to drop the load but was unsure if he activated the dump switch.
Witnesses observed the left main landing gear contact the heliwell. The PIC leveled the helicopter as it descended toward uneven ground; it rolled after ground contact and came to rest on its left side. The SIC exited through his bubble window; the PIC shut off firewall valves and battery switches before exiting. The SIC did not recall making the droop callout in a postaccident interview.
Personnel Information
The 65-year-old PIC held a commercial pilot certificate with rotorcraft-helicopter rating and a private pilot certificate with airplane single-engine land rating. He had type ratings for SK-61 and BV-107. He held a second-class medical certificate issued July 10, 2009, with limitations requiring corrective lenses and glasses for near and intermediate vision. Total flight time was 21,000 hours, with 30 hours in the last 90 days and 30 in the last 30 days. He had an estimated 9,000 hours in the accident make and model. He completed a proficiency check on March 7, 2009.
The SIC held a commercial pilot certificate with rotorcraft-helicopter and instrument helicopter ratings, and a certified flight instructor certificate with rotorcraft-helicopter rating. He was type rated in the SK61. He held a second-class medical certificate issued March 2, 2009, with no limitations. Total flight time was 2,554 hours, with 865 hours in the accident make and model. He logged 38 hours in the last 90 days and 38 in the last 30 days. He completed a proficiency check on February 3, 2009.
Aircraft Information
The helicopter was a Croman SH-3H, serial number 152109. Total airframe time at the accident was 14,354 hours. It had a continuous airworthiness inspection on July 17, 2009. The left engine was a General Electric T58-402 (serial number 281-323) with total time 8,946 hours and time since major overhaul 68 hours. The right engine was a General Electric T58-402 (serial number 281-778) with total time 7,612 hours and time since major overhaul 192 hours. Weight and balance indicated 11,405 pounds; after the accident, the helicopter weighed 11,446.25 pounds, a gain of 40.95 pounds.
Additional Information
The helicopter operated under a Supplemental Type Certificate for an internal firefighting tank system with an internal tank and an 18-foot snorkel. An emergency water release "T" handle was located aft of the center console. The contractor stated no written training procedure existed for drafting operations. It was common practice for the SIC to have a hand near the emergency release. Postaccident examination showed the handle in the stowed position; the SIC stated he did not have his hand near it and it was never pulled. Both tank doors appeared closed.
Tests and Research
Engine examinations revealed no discrepancies. Both fuel control units were tested at Columbia Helicopter, Inc., under NTSB supervision; results indicated they did not contribute to the accident sequence.