[robxorb]

As is often the case almost anywhere in the world, there's a major US military base nearby. In this case it's Diego Garcia, and is absolutely huge:

https://veteranlife.com/military-history/diego-garcia/

"The base is home to thousands of American troops, sophisticated radar, space tracking, and a communications facility."

[JumpCrisscross]

> it's Diego Garcia, and is absolutely huge

You know what’s huger? The Indian Ocean. Add to that the lack of blue-water competition in it and it’s totally reasonable that any birds we have in the area are craning their necks north, not down.

[_djo_]

“Nearby” is doing a lot of work there. The presumed flight path of MH370 went tens of thousands of kilometres from Diego Garcia, certainly outside the range of even the latest over-the-horizon radars. Meanwhile the tracking stations on that base are mostly focused on space activity and missile launches.

No amount of money can break the laws of physics and, like any sensor, radar has fundamental limits in range and resolution. MH370 flew into one of the most remote parts of the ocean it’s possible to reach, it would’ve been a miracle if it was tracked by any radar.

[robxorb]

The presumed flight path at the time it went missing is perhaps relevant, and that was within the vicinity of Diego Garcia, as the flights last few known turns were heading toward it. It seems odd the US would not care nor have tracking ability.

I've seen analysis that showed the flight was within range of several over-the-horizon radars at the time of disappearance and for hours after, ie - someone should know more than we do. As often with such things, I can't find it again.

[_djo_]

OTH radars are not operating all of the time, given the cost to operate them, and are not just covering large areas of ocean all over. They're typically focused specifically on areas of most importance which, for Diego Garcia, would be north toward China, not East toward Malaysia.

Nor do OTH radars always operate at maximum efficiency: They achieve their longest ranges by bouncing signals off the ionosphere, which is severely affected by prevailing space weather.

The only radar that it likely did pass through was Australia's JORN, but the western sector was not operational that night and isn't on 24/7 because of cost constraints.

[robxorb]

Good points but neither of them rule out being reconfigured and used in an emergency, potential hijack situation to locate what could be a significant security threat. Airliners were used for the biggest attack on US ground since WW2. Priority number one.

[_djo_]

Only if there’s enough forewarning, the radar is operational, the aircraft is within its range given prevailing space weather conditions, and that it’s pointing in the right direction. The latter is important because OTH radars are almost all fixed and can’t be steered.

Yes, governments would love to have global 24/7 coverage even over the open ocean. In practice that’s neither possible nor practical.

[robxorb]

> OTH radars are almost all fixed

Given their strategic advantage, you can bet the military will have prioritised steerable.

I disagree with the general premise regarding global coverage. With the US military, capabilities, especially in surveillance, have historically been shown to be decades ahead of what the public thinks is possible.

Personally, if a post appeared tomorrow showing some HN had figured out how to trace the movements of any airliner, without using its adsb and relying instead on anything and everything else that's publicly available, from satellite imagery, to radio frequency data, to radar, even weather data (contrails are often detectable), it would seem cool, sure - but, not unbelievable.

That hypothetically believable scenario would be one person, with no budget, in likely a few weeks or months of their spare time.

The US military has trillions of dollars, the best talent in the world, and decades of dedicated effort in exactly this area, and a propensity to keep such advances secret for decades (as shown recently enough by the Trump photo).

[KeplerBoy]

What's expensive about operating radars?

[_djo_]

At this scale:

1) Electricity usage

2) Staffing costs, both for operational control and ongoing maintenance and support

3) Parts replacement costs. The more you use the radar the faster its components wear out

[KeplerBoy]

Thanks for the reply.

I'm doing research on radars at a lab, but on automotive and robotics scales and operating costs are just not something we consider.

[ianburrell]

Not tens of thousand of kilometers. Diego Garcia to tip of Indonesia is 2800km and 3000km to Australia. But the rest of your post holds.

Also, the over the horizon radars are in Australia. I think they could have picked up the flight but were offline that day.

[_djo_]

Appreciate the correction, I meant thousands.

Yes, that’s the JORN system. The western sector might’ve picked it up if it went near western Australia as presumed, but it wasn’t operating.