Lesson 2 · 15 min
The VDR annual performance test, step by step
You will know exactly what happens in a VDR annual performance test, who may do it, when it is due and what the certificate of compliance must show.
Start here
The 2-minute primer
New to this? These 6 cards explain the lesson in plain words. Go through them first and the lesson will make sense.
Primer done.
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1/6Picture this
A black box needs checking too
An aircraft’s black box records the flight so investigators can learn what went wrong. It is no use if a sensor has been feeding it rubbish for months.
A ship has its own black box, the voyage data recorder. Once a year someone checks that it really records everything it should.
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2/6The big idea
Prove every input reaches the recorder
The recorder captures position, speed, heading, the radar picture, bridge voices, radio calls, engine and rudder orders and alarms. It stores them in tough capsules, one of which floats free on newer ships.
Sensors fail quietly. So once a year an approved technician cuts the power to test the backup battery. They test the locator beacon, check the capsules and record 12 hours of data for the maker to analyse.
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3/6Words you'll meet
Six words, in plain English
- VDR
- voyage data recorder, the ship’s black box that records what happens on the bridge.
- Capsule
- the tough protective box that holds the recorded data, built to survive fire, impact and deep water.
- Float-free capsule
- a capsule that breaks loose and floats up if the ship sinks, then sends a signal.
- Acoustic beacon
- a small underwater device on the capsule that sends a homing sound so searchers can find it.
- Reserve power
- the backup battery that keeps the recorder running for about two hours after a power cut.
- Certificate of compliance
- the paper from the testing company, kept on board, proving the yearly test was passed.
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4/6Why it matters
When the worst happens, the data must be there
After the cargo ship El Faro sank, her recorder let investigators rebuild the last day on the bridge. It also showed a broken wind sensor had been recording wrong data.
A missing certificate, or a recorder that doesn’t record everything, can bring a deficiency or detention in port.
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5/6In this lesson
What you’ll be able to do
- Follow the yearly test step by step on board.
- Know who is allowed to carry out the test.
- Know when the test is due and how the certificate arrives.
- Spot the gaps that inspectors find, like dead sensors and old batteries.
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6/6Quick check
What does the yearly test mainly prove?
Right: the test proves the whole system, sensors included, really works, and the ship keeps the certificate on board.
The basics
On 1 October 2015 the cargo ship El Faro sailed into Hurricane Joaquin and sank with all 33 people on board. Ten months later a US Navy remotely operated vehicle lifted her VDR capsule from 15,250 feet below the surface. It held more than 26 hours of bridge audio from six microphones, radar images and ship’s data, and it let the National Transportation Safety Board reconstruct the last day on the bridge minute by minute. It also exposed a sensor fault that had gone unrepaired: the officers had remarked that the anemometer was not working, and the wind data the VDR had recorded were wrong.
That is what the VDR annual performance test is for: once a year an approved technician proves that every required input reaches the recorder, that recording survives a power loss, that the capsules can be found and the data read back. A sensor that has been dead for months should be caught here. This lesson walks through the test as it happens on board.
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In the rest of this lesson
- Try it: A VDR annual performance test from planning to certificate
- In plain words
- In detail
- What the rules say
- Flag and class notes
- Key numbers
- What inspectors find
- 3 questions people ask
- Quiz: 6 questions
- Ask our engineers about this lesson
Familiarisation training from Al Safwan Academy. Finishing a course shows completion of online familiarisation training: it is not an STCW, flag-approved or manufacturer qualification, and these courses don't replace that training. The manufacturer's manual and your flag's rules always come first.