– Guy Gratton
The Malaysian Insider
7 March 2015
The disappearance of Malaysia Airlines flight MH370 a year ago has led to one of the largest search exercises in history. The 140-tonne aircraft and all its 239 passengers and crew remain missing, and the search continues across 17,000km² of ocean up to 5km deep. For comparison, we knew within 20km where the 50,000 tonne Titanic sank in 1912, in water 4km deep – and even then it took 73 years to find it.
A steel ship is much easier to find than an aluminium aircraft because it has a far larger effect on the earth’s magnetic field and so is easier to detect. More obviously, locating something as big as a cruise liner based on a fairly good knowledge of the location is much easier than finding a much smaller aircraft in a large area of the Indian Ocean.
Why don’t we know where MH370 went, wasn’t it being tracked? Near to major cities and population centres, state air traffic control uses primary radar – which locates objects using reflected radio waves. But radar’s range is only a few hundred miles, and while airliners carry their own radar this is calibrated for detecting storms and mountains, not other aircraft. Continue reading “Why we must keep searching for MH370”