Did my TR in 2000 with an ex Fokker instructor. As a previous post said, was very sternly warned to NEVER attempt take off with ANY contamination, and, a tactile inspection was highly recommended, in some companies it was actually mandatory.
I lost count of how many times I got it wrong visually, to be corrected by touch.
This accident to his ex Fokker colleague was the reason for the warning, along with extensive windtunnel work done by Fokker subsequent to the loss of the factory pilot.
https://en.wikipedia.org/wiki/Palair...nes_Flight_301
Repeated , with only one unfortunate truck driver lost, several years later in France.
Report: Regional F100 at Pau Pyrenees on Jan 25th 2007, crashed on take off due to contaminated wings