Also in Figures 4 and 5, particularly for the longitudinal estimates, as can be seen from the average performance, an "advanced indication" of the icing level was encountered.
For longitudinal parameter, a certain delay was encountered for various icing levels denoted by dotted lines.
It is understood investigators are probing whether the pilot dropped the copter down below "icing level
" to avoid a potential catastrophe with the helicopter's blades or windscreen freezing up.
An aviation source said: "The icing level
was measured at 2,800ft in the area by a police helicopter pilot soon after he landed near the crash site.
If you're not inclined to dig into the weather charts, make sure you have a full picture of icing levels
along your route of flight when you talk to the briefer.
Ice accident scenarios, Neil said, usually involved some maneuver requiring long exposure to low-altitude icing levels
, such as a DME arc.
I gave him all the weather data and made sure I told him about the icing levels
Moderate icing levels
should have the pilot considering a way out, while severe icing requires immediate and decisive action, even in protected aircraft.