Communications (in a) Disaster

Last week, the governments of Vanuatu and Australia announced a three year project to build out a national emergency communications network. Which is great. I haven’t seen any details on the particular technologies being proposed, but I suspect that High Frequency, or HF, radio will be the most likely choice.

HF relies on the particular dynamics of the ionosphere to quite literally bounce radio waves off it, allowing it to reach past the curvature of the Earth.

It also doesn’t require these:

Which is probably for the best, after a cyclone.

That tower, by the way, has just been reconstructed, but has yet to be reconnected to the company’s network. That’s seven months without service. Through no fault of the company’s, materials were delayed for months due to decisions relating to the COVID-19 crisis.

The kind of HF radio antennas (antennae?) we use in most commonly in Vanuatu look more like this:

They’re smaller and cheaper than microwave antennae(s), easier to configure, and best of all, they can be unstrung during a cyclone, and then resurrected after the storm has passed.

Can be.

In 2004, cyclone Ivy bopped like a pinball down the length of Vanuatu’s archipelago. One of the first islands hit was Ambae. Where (because the Gods hate me, I guess) I just happened to be visiting.

When we emerged from the debris the next day, comms were out. Turns out that no one at the provincial emergency operations centre remembered to take the HF antenna down. Fixing the broken antenna wasn’t a huge technical challenge. The hard part was convincing people (myself included) that I was qualified to do it. From a 2004 blog post:

I asked one of the provincial staff for a two-metre length of nylon rope in order to create a makeshift climbing harness. He disappeared, returning a few minutes later with quarter-inch nylon twine. We chuckled ruefully and made do. I doubled the twine, then doubled it again, and tied the resulting loop around the pole with a double prussic knot. A prussic knot slips one way only, so each of the knots would push against the other, tightening the bond as weight was put on it. I climbed up two metres, and tested, then re-tested my harness. Finally satisfied that it would hold my weight, I climbed up.

I wasn’t too concerned about the climb, in spite of the missing steps. It’s a fairly easy thing to shinny up a pole, and it was something I’d done more than once in my mis-spent youth. The trouble would come when I needed both hands free to heft the thirty metres of steel cable to a proper height.

After a little to-ing and fro-ing in the breeze, I managed to get myself set. I fed the free end of the re-spliced cable down to the men on the ground, and relying on them to take up the slack, I began to tug. I put what weight I have against the harness and heaved for what I was worth. It was gratifying to watch the antenna rise slowly above the trees. With the assistance of a well-positioned cleft bamboo pole, we managed to lift the antenna higher than it had been before. Last I heard, they had managed to contact Mota Lava, an island a few hundred miles to the north in the Banks group, as well as the neighbouring islands of Maewo and Pentecost.

And that, children, is how daddy restored comms to Penama province’s emergency operations centre.

(Post scriptum: I went back to the island about 4 years later. My patch job was still there.)

On the bright side, HF radio equipment is easier to secure—and repair if necessary.

On the not-so-bright side, it’s debatable whether it would have been repaired if I hadn’t just happened to be there. It took a week for flights to resume, and longer for the response to get underway, because—as with cyclone Pam in 2015—Port Vila got hit really hard too.

That said, an inter-island police network would be quite useful outside of cyclone season too, especially when trouble boils over from one island to the next.

But to assume that it will provide primary emergency communications in the wake of a cyclone, which is the most likely cause of disaster-related emergency in our neck of the water—well, it’s a bit of a stretch. The one thing we know about cyclones is that comms cut out right when you need them most.

The reason we objected to the end of Radio Australia’s shortwave service is precisely because it was far away from us. So when our communications networks are knocked ass over tea kettle, someone will still be able to reach us.

Short wave and High Frequency radio work. Digital, FM, Microwave and other point to point technologies require either a physical link or line of sight. They don’t do so well when the wind is blowing strong.

I suppose we could build out an inter-island fibre-optic network, though. That would be cool. And about a hundred million bucks.