re: One dead 30 injured on London-Singapore flight

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They definitely flew through something, this wasn't CAT, it was likely a cell that didn't paint much. The Honeywell RDR-4000 radar doesn't do tilt settings, instead, it scans all tilts at once and displays weather as either "at your altitude", or "below you" (crosshatched out on the display). At tropical latitudes the tops of the cells are all ice crystals and don't paint much, I've seen a lot of cells that are clearly above FL400+ but are hatched out on the display. You go around everything even if it's hatched out when flying near the ITCZ. Fly around with max gain so the weak returns actually show up. Also have to wonder if maybe they inadvertently had the WX display opacity turned down? Kind of a gotcha in the 777, you can dim the radar display on the ND to the point that it may not be apparent there's something painting. Most guys I know fly around with it on max brightness all the time and have that as part of their preflight flow.

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The aircraft involved is equipped with a weather radar in the nose. It is usually very effective at showing the pilot the location of rain storms and other conditions that could cause turbulence so that they can avoid them. In tropical regions, thunderstorms can become so large and reach such high altitudes that they become ice. The weather radar is less effective at detecting ice than it is water. Experienced pilots know this and will divert around weather in these regions, even if the radar shows it is below their current altitude. The suspicion is that this flight crew did not do that, or may not have had the sensitivity of the radar set high enough to detect ice.

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Aircraft mechanic here, with an avionics specialty. The true high-risk and dangerous events occur in heavy thunderstorm cells. Even in severe turbulence like this 777 went through, it isn't at a very high risk of actually getting damaged. The Flight data recorder will have to be evaluated for g's on the airframe, and that will determine what kind of inspections the airplane will need before it can fly again. Severe turbulence is technically classified as sudden onset, or strong enough motion where the aircraft is temporary at a loss of control. The autopilot would definitely get kicked off, and the pilots may struggle to regain safe control. This could be several g's, both positive and negative. This for sure could over stress the airframe, but barring any massive structural issues which would've already been caught, it is (by a wide margin .... but nothing is perfect) not in actual danger of damage. That by no way discredit the terrifying experience in the cabin. Anything dangerous enough to actually damage the aircraft, is already avoided in large cells. Heavy precipitation like actual hail, or super heavy rain will paint the weather radar like crazy. Clear air turbulence (CAT) and other weird issues like ice clouds, or precipitation that doesn't paint the radar enough does happen, but the truly dangerous events throw clear enough signs that the pilots will avoid at all costs.

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One passenger has been killed

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