The Air Accidents Investigation Branch (AAIB) report said the wheel's outer bearing had seized.
The helicopter will now be taken for examination by the Air Accidents Investigation Branch (AAIB).
The Air Accidents Investigation Branch (AAIB) said it was sending two staff to Kathmandu to assist local authorities.
Four inspectors from the Air Accidents Investigation Branch (AAIB) are at the crash scene carrying out an inquiry.
The Air Accidents Investigation Branch (AAIB) said their actions increased the risk of a fire on board the plane.
BBC: NEWS | Europe | Isle of Man | Air crew criticised for fire risk
An Air Accidents Investigation Branch (AAIB) report said she weighed less than the recommended pilot weight range for the glider.
The Air Accidents Investigation Branch (AAIB) said the crew carried out the controlled ditching due to a system failure warning.
The Air Accidents Investigation Branch (AAIB) said the aircraft, by modern standards, had "low stability and power margins and poor flight instrumentation".
The Air Accidents Investigation Branch (AAIB) found there was a rotor blade fault that caused them to strike the craft and separate.
Crash investigators from the Air Accidents Investigation Branch (AAIB) have been at the scene and the wreckage of the aircraft has now been removed.
Last year, a report by the Air Accidents Investigation Branch (AAIB) found no technical reason for the crash, but said a technical fault could not be ruled out.
The sheriff's findings go further than an Air Accidents Investigation Branch (AAIB) report, published in February 2009, which found no cause could be positively determined into the tragedy.
There have been 12 serious incidents involving helicopters in the capital in the last 20 years, according to the UK Air Accidents Investigation Branch (AAIB), but none involving fatalities.
BBC: London helicopter crash victim Matthew Wood killed in fire
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