Robinson R44 II N442RN

Summary

On 2 May 2013 at about 22:50 local time, a Robinson R44 II registered N442RN, operated by Leading Edge Aviation, was involved in an accident near Pomeroy, Washington, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

2 May 2013 at 22:50

Classification

Accident

Location

Pomeroy, Washington, United States

Coordinates

46.4864, -117.4214

Aircraft

Robinson R44 II

Registration

N442RN

Category

Helicopter

Engines

1

Operator

Leading Edge Aviation

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Route

Pomeroy → Pomeroy

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR13LA217

Nobody was injured.

The pilot's failure to ensure that the helicopter was properly loaded, which resulted in the helicopter being in excess of its maximum allowable gross weight and led to a loss of main rotor rpm on takeoff. Contributing to the accident were the ground crewman's inadvertent overloading of the helicopter and the design of the spray tank's visual sight glass, which did not allow the pilot to visually verify the amount of the spray tank load without exiting the helicopter.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

Before the agricultural application flight, the pilot asked the ground crewman to refill the spray tank with 50 gallons of chemical solution; 10 gallons of aviation fuel was also added. Subsequently, the ground crewman signaled to the pilot that the helicopter was ready to depart. During the departure and while transitioning to forward flight, the low-rotor rpm horn activated, and the pilot immediately pushed the emergency dump button to lighten the load; however, the rpm continued to decrease, and the pilot initiated a run-on landing to a field. During the landing, the pilot was unable to maintain control as the left skid dug into the dirt, which resulted in the helicopter nosing over and coming to rest on its left side.  The pilot reported that he believed the amount of solution added to the tank was more than 50 gallons, which placed the helicopter outside of weight and balance and performance limitations. The pilot added that the spray tank sight glass is long and very shallow, and that, unless the helicopter is level, the sight glass reading is inaccurate. Additionally, when seated in the helicopter, it was not possible for the pilot to see the spray tank sight glass or know how much spray solution had been loaded into the tank. Therefore, the pilot had to rely either on the ground crewman or exit the helicopter after each load and visually check the load to ensure that the helicopter was loaded with the proper amount of chemical solution. The pilot reported no mechanical malfunctions or failures with the helicopter that would have precluded normal operation.             

Quoted verbatim from the NTSB record.