Voyager 2.5 - Detailed Analysis of Failure 

This article aims to provide a detailed representation and interpretation of each piece of evidence obtained from the voyage and subsequent failure of the Voyager 2.5 within the entrance to Western Port.

Voyager 2.5 was approaching the entrance to Western Port, but stopped sailing near 12th July, 11pm and drifted back out to sea with the tide. This was against the South Westerly wind of around 15 to 20 knots. Rather than drift back into Western Port with the change of tide, she drifted east toward Cape Woolamai, for about 19 hours. 

Then she spontaneously turned left and drift north straight on the rocks near Pyramid Rock.

The whole time she was drifting, the winds remained fairly constant from the South and South West. Despite this, she suddenly changed course and headed for the rocks.

Voyager 2.5 as found at low tide, the next morning

View of Voyager showing the equipment containers still intact

The equipment compartments were intact, but about 50ml of water had leaked in to the main compartment.

The smaller forward compartment containing the satellite tracking equipment remined dry and fully operational.

The electronic components in the main compartment suffered significant electrolytic corrosion around the power circuitry.

The computer includes an SD Card for logging many of the vessels sailing parameters.

Fortunately, the SD card is intact and all log files are accessible.

Path of Voyager after failing to enter Western Port, through to the rocks

Each time the computer boots up, it increments a Boot number.

The mission commenced with Boot #501.

The log files showed that the computer stopped logging data about 18 minutes after the failure occurred.

About 19 hours later, the computer started again with Boot #502 and ran for about 5 minutes.

This coincided with the vessel commencing to drift in shore.

Then the computer rebooted again with Boot #503 and ran for 12 minutes.

It then washed on to a rocky beach. The computer did briefly restart with Boot #504 for a few seconds about 3 hours later.

Detail of movement of Voyager near the time of failure.

Detail of movement of Voyager near the time turn to run ashore

View Log Analyser visualising the vessel state after the failure.

The previous image is taken from the Voyager Log Analyser software. This is part of the Voyager suite of software that is used to visualise the vessel state and sailing parameters.

The wind is coming from the South West, and is confirmed by the AWA in the image.

The vessel is drifting out to sea, as confirmed by the COG in the image.

The vessel is lying beam on to the wind.

The rudder command is trying to turn to port, but the vessel is not responding.

This implies that the steering is ineffective.

This could be due to mechanical damage or electrical damage.

On balance, it is most likely electrical damage, due to water ingress around the Wing Angle Sensor housing.

The following video is a screen recording of the Voyager Log File Analyser.

It shows the first minutes of Boot #502. It shows the moments after the computer has started up and establishes its location. the boat id lying broadside to the wind on the starboard tack. As soon as location is established, then it tries to turn the vessel, and it responds in seconds.

This transition can be seen in the first 20 seconds of this recording.

It is unclear if the vessel can steer properly, but it appears that the vessel does have an intact steering mechanism, and it was responsive to the computer.

The recording also shows that the Wing Angle sensor is probably faulty, constantly showing an apparent wind of -6 degrees, off the bow. If the vessel could steer, it would be constantly trying to bear away from what appears to be a head-on wind.

Detailed log of events

Note: Temperature is measured by the Wing Angle sensor, located within the sensor housing at the base of the mast.

• 11/7/2022 07:27:04 Switch on at Torquay Boot #501
• 12/7/2022 14:53:21 Turn at the Cape Schanck waypoint
• 12/7/2022 16:52:44 Temperature reading drops from 15 to 14 degrees C.
• 12/7/2022 22:50:46 Temperature reading increases from 14 to 15 degrees C, after about 6 hours.
• 12/7/2022 22:52       Approximate time of failure
• 12/7/2022 22:52:09  Steering command is trying turn hard to port, the vessel is not responding.
• 12/7/2022 22:56:46 Temperature reading increases from 15 to 22 degrees C, after about 6 minutes.
• 12/7/2022 23:09:46  Temperature reading increases to 82 degrees C.
• 12/7/2022 23:10:12 End of logging Boot #501

• 13/7/2022 18:04:49 Start logging with Boot #502
  Note: The Steering servo would be commanded to centre as part of boot up.
• 13/7/2022 18:05:13 The rudder is commanded to steer to port.
• 13/7/2022 18:05:16 The vessel has responded and turned 90 degrees to port. No longer lying beam on to the wind. No longer held in hove-to state.
• 13/7/2022 18:10:24 End of logging Boot #502

• 13/7/2022 18:10:35 Start logging with Boot #503
• 13/7/2022 18:23:16 End of logging Boot #503

• 13/7/2022 21:05:39  Boot #504, a few seconds only.

Link for plot of positions reported via satellite:

https://maps.findmespot.com/s/VG5D

Interpretation

It appears that the steering failed.

This could be due to mechanical damage or electrical damage.

On balance, it is most likely electrical damage, due to water ingress around the Wing Angle Sensor housing.

It appears that the temperature sensor within the Wing Angle Sensor started to return faulty data in the minute or two prior to the failure. 

The implication is that the sensor was suffering water damage, in the minute or two prior to failure occurring.

The boat drifted in a hove-to situation for 19 hours after the failure.

For this to occur, the rudder would be turning the vessel to starboard, trying to steer too high to the wind.

It seems likely that the steering failed when the rudder was steering to starboard, and then didn't return.

The vessel left the hove-to position at 6:05pm the next day, at the same time that the computer booted up a second time.

When the computer boots up it initially commands the steering servo to centre the rudder.

It appears the steering may have been partially working, to allow the rudder to move and release the vessel from a hove-to state. She then drifted ashore.

This further reinforces the point that the rudder was mechanically operational while at sea, and the failure was due to electrical faults, due to water ingress.

Further Leak Testing 

Water was found in the equipment compartments, and it must be understood how it got in.

The equipment compartments (excluding the Wing Angle Sensor housing) were tested by placing under water with a covering depth of about 20mm for 12 hours. 

There was no measure water leak during this time.

The Wing Angle Sensor housing was tested separately by placing it under water for 12 hours.

A significant amount of water leaked in.