Aviation occurrence briefs

Collision with terrain involving remotely piloted aircraft, at Hope Downs 4 Mine, WA, on 13 May 2018

Status: Completed
Investigation completed


Occurrence Briefs are concise reports that detail the facts surrounding a transport safety occurrence, as received in the initial notification and any follow-up enquiries. They provide an opportunity to share safety messages in the absence of an investigation.

What happened

On 13 May 2018, a remotely piloted Da-Jiang Innovations (DJI) Phantom 4 aircraft was launched from a lookout near Hope Downs 4 Mine, with the pilot and observer intending to conduct an aerial berm[1] inspection within one of the mining pits. At about 0735 Western Standard Time, the aircraft lost power and fell to the pit floor, resulting in the aircraft being destroyed.

During the flight, witnesses observed the battery separate from the body of the aircraft and fall to the ground. An inspection revealed hairline fractures around the catch, which locks the battery in place. The recovered battery was also fractured in this area.

Later, it was determined that a post-flight check had not been completed on the previous flight. In addition, the pre-flight inspection of the aircraft just prior to the accident flight had not included a check of the battery connection and locking mechanism.

Safety action

As a result of this occurrence, the remotely piloted aircraft operator has advised the ATSB that they have taken the following actions:

  • modifying their procedures to include the recording of all maintenance activities to their sub 2 kg remotely piloted aircraft
  • including in their pre-flight checklist that the observer or a secondary person will check the installation of the battery.

In addition, the operator has emphasised the importance of pre and post-flight checks of the aircraft.

Safety message

This accident highlights the importance of pre and post-flight inspection of remotely piloted aircraft. Aircraft manufacturer user manuals, which are generally accessible online, provide specific guidance in relation to each model of aircraft, including information in relation to the correct fitment of the battery. Additionally, the Civil Aviation Safety Authority provides generic guidance in relation to the operation of remotely piloted aircraft and the training requirements of operators on their Flying drones/remotely piloted aircraft in Australia web page.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.


  1. Berm is a term used to describe a barrier, such as a wall.
General details
Date: 13 May 2018   Investigation status: Completed  
Time: 0735 WST    
Location   (show map): Hope Downs 4 Mine    
State: Western Australia    
Release Date: 17 October 2018   Occurrence category: Accident  
Report status: Final   Highest injury level: None  

Aircraft details

Aircraft details
Aircraft model Da-Jiang Innovations (DJI) - Phantom 4  
Type of operation Aerial Work  
Sector Remotely piloted aircraft  
Damage to aircraft Destroyed  
Last update 12 December 2018