I am disturbed at the information the media are getting from senior ministers, and from unnamed or non-official sources, claiming great difficulties in detecting wooden boats moving in stormy weather across large areas of ocean.

An impression is being created that Australia’s $1800 million  long-range radar detection system covering Australia’s northern maritime approaches, JORN — a crucial asset in the defence of Australia against maritime or air intrusions of any kind, including terrorism — is unreliable at such times. This might be politically convenient in the Christmas Island tragedy context, but it is not sustained by a simple study of publicly accessible facts. See the Google Wikipedia entry on radar, a detailed technical article, and the Department of Defence DMO and Wikipedia articles on JORN.

JORN is a long-distance all-weather radar system: one of many such around the world. JORN is highly admired internationally as one of the most powerful of these systems. Prime Minister Julia Gillard and and Home Affairs Minister Brendan O’Connor have implied in the past 24 hours that bad weather around Christmas Island “limits” the ability of radar to detect a wooden boat (Gillard), which is “nigh on impossible” (O’Connor). They have not said categorically that this particular boat was not detected by JORN. They have said it was not “tracked”, whatever that might mean. They have stressed the local bad weather around Christmas Island at the time. But this is irrelevant to JORN, which is a long-distance system designed to detect and maintain coverage of  incoming boats as early as from the time they leave shore in Indonesia, over the duration and distance of the voyage (480 kilometres, average voyage time up to 36 hours). The task is eased because the boats are funnelling into two point destinations, Christmas and Ashmore islands.

Let’s assume that heavy storms prevailed all along the route for the whole journey of this boat. It is true that storms create “clutter” (interference) in radar systems such as JORN, but there are standard operational techniques for separating out the desired target signal from the clutter: defence radar and radar systems around major airports do not fail in stormy weather. The operators just work harder in disentangling the target signals from the surrounding clutter. They have many hours in which to do so, verifying and strengthening any initially unclear signals.

It’s clear from the successful detection and interception of well over 100 boats since 2007, in a range of weather conditions encountered en route at different times of the year,  that this operational problem,  such as it is,  is routinely overcome. I am not aware of any boats that have arrived without Border Protection Command knowing beforehand that they were coming — until this one.

As to wooden vessels,  metal objects are certainly easier to pick up on any radar than wooden objects because of their high electrical conductivity. But as long as boats have some metal in them, as all these boats do in their motors and propeller shafts, they are detectable. Again, the proof is in Border Protection Command’s past high success rate.

That this boat was not “tracked” could mean many things. It need not mean that JORN raw radar data was not collected. It could mean that something went wrong at a subsequent stage along the detection-interception system, from JORN data collection to reading and processing of that data to firm identification of an incoming vessel to issuance of orders to a Border Command vessel to intercept. This is a long chain of decision and command involving many people, as SIEV X Senate evidence made clear in 2002. There are several points on the way at which it could come unstuck, but I am not going to speculate on this.

A conclusion of the 2002 Senate inquiry into SIEV X was that border protection operations must at all times put high priority on protecting human life of crews and asylum seekers.  To me this suggests that in a period as now when boats are coming pretty regularly, the JORN-based detection and interception system needs to be most particularly vigilant and diligent at times of bad weather around Christmas Island, because the consequences of a failure to detect can be so much more tragic as we just saw.

I welcome the PM’s announcement at a press conference that “there will be an immediate review carried out by Customs and Border Protection. This will involve an initial collection of facts and the initial assessment identifying any immediate action required”. I look forward to seeing concrete follow-up to this announcement. I note that Border Protection Command is investigating itself here, and in private. The Prime Minister is asking a lot of Border Protection Command here. I would be happier if there were some kind of independent outside involvement. And speed is vital, while data is accessible and memories of what was done or not done last week are most fresh.

I hope people in the system are keeping detailed diaries of all that they remember from last week; and will be ready to share their memories as necessary when the time comes. Or else this could all happen again, as it has happened nine years after SIEV X.