Aviation occurrence briefs

Pitot tube blockage involving an Aeroprakt 32, Moorabbin Airport, Victoria, on 14 August 2019

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 14 August 2019 at approximately 1500 Eastern Standard Time, an Aeroprakt 32 was conducting a training flight from Moorabbin Airport, Victoria, with an instructor and a student on board.

During the take-off run, the crew detected that the airspeed indicator (ASI) was indicating zero and subsequently rejected the take-off. The aircraft then taxied off the runway.

Following the incident, an engineering inspection was carried out. It was determined that the pitot tube was blocked, likely from water. A blocked pitot tube affected the accuracy of the ASI, resulting in fluctuating or zero speed indications.

A test flight was subsequently conducted and the aircraft was returned to service.

Safety action

As a result of this occurrence, the aircraft operator has advised the ATSB that they are taking the following safety actions:

  • ensuring all aircraft are allocated pitot tube covers
  • issuing a safety reminder to all pilots to fit pitot tube covers after all flights and report if a pitot tube cover is missing.

Safety message

This occurrence highlights the importance of pre-flight checks, as well as the use of pitot tube covers to minimise the risk of the aircraft departing with an unserviceability. Pitot tube covers are designed to prevent foreign objects from entering the pitot tube while the aircraft is stationary.

It also serves as a reminder to be aware of unreliable or erroneous airspeed indications during the take-off run. If detected and it is safe to do so, abort the take-off.

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.


General details
Date: 12 August 2019   Investigation status: Completed  
Time: 1500 EST    
Location   (show map): Moorabbin Airport    
State: Victoria    
Release Date: 23 September 2019   Occurrence category: Incident  
Report status: Final   Highest injury level: None  

Aircraft details

Aircraft details
Aircraft manufacturer Aeroprakt Ltd  
Aircraft model Aeroprakt 32  
Type of operation Flying Training  
Sector Piston  
Damage to aircraft Nil  
Departure point Moorabbin, Victoria  
Destination Moorabbin, Victoria  
Last update 23 September 2019