Posted by:
alsd
(
)
Date: December 03, 2019 03:01PM
Dr.No Wrote:
-------------------------------------------------------
> Thought was hubris plus weather but
>
> K9V9 301835Z AUTO 02006KT 1/2SM SN OVC005 01/01
> A2930
>
> Decodes Chamberlain Municipal Airport, Nov 30
> 12:35 p.m. local, automatic weather, wind 020 at 6
> knots, visibility one-half statute mile in snow,
> overcast 500 feet, temperature 01 dewpoint 01
> centigrade, altimeter 2930
>
> So weather wasn't really that bad. Ice
> contaminating flight surfaces should not have been
> a factor - especially flying an anti-ice
> turboprop. If pilot was not thoroughly comfortable
> flying in this stuff could have gotten spatially
> disoriented on entering the goo but this is a head
> scratcher
This was pure hubris on the part of the pilot. The PC-12, which I used to fly, is certified to carry a maximum of 11 people, one pilot plus 10 passengers, or two pilots and nine passengers in a high density configuration. Most private and executive PC-12 are configured for six passengers and two pilots. Going from Pilatus' information, 12 occupants, plus standard bags, and fuel for a roughly three hour flight plus standard IFR reserves would have put the aircraft several hundreds of pounds over maximum certified takeoff weight. It was also reported that the town just south of Chamberlain had reported 8 inches of snowfall immediately prior to this aircraft departing. We do not know what, if any, pre-takeoff deicing was applied to the aircraft. The PC-12 deicing equipment only works in flight and will not remove snow and ice accumulation on tops of the wings, tail, and fuselage. The PC-12 utilizes de-ice "boots", which are pneumatically operated inflatable rubber bladders on the leading edge of the wings and tails. In flight, ice will accumulate on the leading edges. The technique is to allow the ice to accumulate and then periodically inflate the "boots" which breaks away the ice the has accumulated. On the PC-12, it works on a cycle. In any case, if there was any ice or snow accumulation on the aircraft before it took off, the aircraft would have weighed even significantly more. Combine an overweight aircraft with the loss of lift from a potentially contaminated wing, and you have a recipe for disaster.
In the professional pilot community it is widely recognized that the most dangerous people in the sky are rich people flying their own airplanes.
Here is a link to a video which shows the operation of the boots on a PC-12:
https://www.youtube.com/watch?v=EbElryR9h3c