Originally Posted by
phiggsbroadband
There are conventions used in the measurement of weather radar reflectivity...
Quote...
When describing weather radar returns, pilots, dispatchers, and air traffic controllers will typically refer to three return levels:
[20]
- level 1 corresponds to a green radar return, indicating usually light precipitation and little to no turbulence, leading to a possibility of reduced visibility.
- level 2 corresponds to a yellow radar return, indicating moderate precipitation, leading to the possibility of very low visibility, moderate turbulence and an uncomfortable ride for aircraft passengers.
- level 3 corresponds to a red radar return, indicating heavy precipitation, leading to the possibility of thunderstorms and severe turbulence and structural damage to the aircraft.
Aircraft will try to avoid level 2 returns when possible, and will always avoid level 3 unless they are specially-designed research aircraft.
This flight and flight-plan took the aircraft through Yellow and Red areas on the weather radar plot, and contact was lost as it approached the second red area, almost to within a mile.
Those are the known facts...
Your post is correct - but pilots need to be aware that the radar is showing reflectivity from rain not turbulence. (I realize with some I am teaching grandmother to suck eggs here) Apart from some military aircraft with funny paint-jobs most aircraft can manage rain quite successfully. It is turbulence and hail that need to be avoided. Unfortunately, as posts on this thread have noted, rain reflections and turbulence are not always together, indeed extreme turbulence can be found between the radar reflections. Not only that but hail can have a significant 'throw' out of the top of storms and that is why the FAA advise 20 NM separation from large Cb. That is not always possible of course places like the area in question in this post, South Texas and Florida would be unflyable if 20NM were always taken. But be extremely cautious of a natural assumption that red is where the danger is, it is just the area of strongest radar returns. So 3D radar may look everso pretty and really wow the management, but it may not be the tool required to avoid dangerous turbulence, that may be (to the dismay of management) training and experience of the crew.
As always experience is a hard teacher as the exam comes before the lesson. So try to learn from experienced pilots who have had the exam, passed it and learned from it.