Aviation Accident Summaries

Aviation Accident Summary WPR10LA354

Salt Lake City, UT, USA

Aircraft #1

N944DW

ROBINSON HELICOPTER COMPANY R44 II

Analysis

The pilot had just landed the helicopter on a flatbed trailer when it was determined that it needed to be moved laterally in order for its skids to be correctly attached to the trailer. Therefore the pilot applied enough collective to make the helicopter "light on the skids," and then he applied cyclic input meant to slide the helicopter laterally. When the helicopter did not slide sideways as the pilot desired, he continued to apply left cyclic input, whereupon the helicopter suddenly began to move in a manner that resulted in it starting to fall off the trailer. During the pilot's attempt to regain directional control by lifting the helicopter clear of the trailer, its main rotor blades came in contact with the truck that the trailer was attached to. Once the blades contacted the truck, the helicopter rotated about 180 degrees and impacted the tarmac beside the trailer. Soon after it impacted the tarmac, a fast-growing fire began. During the accident sequence, an individual who was helping with the loading process was struck by a main rotor blade.

Factual Information

On July 16, 2010, about 1530 mountain daylight time, a Robinson R-44 II helicopter, N944DW, impacted the asphalt parking ramp between a row of hangars at Salt Lake City International Airport, Salt Lake City, Utah. The commercial pilot and his passenger received serious injuries, one person on the ground received serious injuries, and one person on the ground was killed during the accident sequence. The helicopter, which was owned by Veracity Leasing LLC, and operated by Pathfinder Helicopters, sustained substantial damage. The 14 Code of Federal Regulations Part 91 repositioning flight took place in visual meteorological conditions. No flight plan had been filed. According to the operator, the pilot planned to take off from the asphalt ramp and land on a flatbed trailer that was connected to a pickup truck located a few feet away. Then, once strapped down, the helicopter was to be taken by trailer to a distant location. According to the pilot, at the beginning of this process, he and one of the individuals that was helping with the loading sequence, wheeled the helicopter out of the hangar, and then once the helicopter was fully clear of the hangar, they removed the ground-movement wheels from the helicopter's skids. The pilot then had the individual who had helped him roll the helicopter out of the hangar get into the left front seat of the helicopter, in order to equalize the lateral load while he was landing on the trailer. The pilot then picked the helicopter off the ground and hovered over to the location of the trailer. He then successfully landed on the trailer, lowered the collective, and rolled the throttle to ground idle. At that time another individual who was helping with the loading process approached the trailer to take a look at the positional relationship between the helicopter's skids and the skid locks on the trailer. It was then determined that the helicopter might have been too far to the right to get the skid locks to fasten on the skids. Therefore the person who had approached the trailer tried to fasten the skid locks down, but was unable to get them to fully close. After talking to the individual on the ground, the pilot decided to, "… raise the collective to get light on the skids and slide a couple of inches over to the left." He therefore brought the throttle to flight idle, and raised the collective, "to get light on the skids." According to the pilot, during this process he, "…did not lift off the trailer." He then used cyclic inputs to try to get the helicopter to move to the left, but initially he was unable to get it to move. He therefore continued trying to get the helicopter to slide to the left, and eventually, "… it just gave way." At that point, the nose of the helicopter went left, and the aft part of the right skid went off the trailer, and the helicopter, "… started to fall off the trailer backwards." In an effort to lift the helicopter clear of the trailer and regain directional control, the pilot immediately applied up collective and forward cyclic. These actions resulted in the helicopter lifting off the trailer, but because of the forward positioning of the cyclic control, the main rotor blades tilted forward and impacted the cab of the pickup truck. Once the rotor blades made contact with the truck, the helicopter spun around about 180 degrees and impacted the tarmac beside the trailer. During that sequence, a main rotor blade hit the individual standing next to the trailer, the right seat passenger was ejected from the helicopter, and one other person on the ground was injured seriously. After the helicopter impacted the tarmac, because the engine was still running and the rotors were still turning, the pilot disengaged the rotor clutch, turned the master switch off, and turned the keys to the OFF position. Just as the pilot was turning the key to the OFF position, a rapidly growing fire started on the outside of the helicopter. The pilot then unhooked his seat belt and crawled out of the helicopter through the broken front windscreen. The pilot then helped the ejected passenger, who was kneeling on the left rear portion of the trailer, to get away from the accident scene. The pilot and another person then pulled the individual who had been hit by the rotor blade away from the wreckage and fire. A Federal Aviation Administration (FAA) directed/monitored post-accident inspection of the helicopter wreckage did not reveal any evidence of an engine or flight control malfunction or anomaly, and the operator of the helicopter indicated on the NTSB Form 6120.1 that there had not been any mechanical malfunction or failure.

Probable Cause and Findings

The pilot's loss of directional control while attempting to move the helicopter laterally without first lifting it fully off its landing platform.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports