You do not change a pilot because they have run into turbulence.
You can offer the pilot ground assistance. If there is a co-pilot, great, that support system helps.
But decision making and accountability lie with the pilot.
Otherwise, why are they in the cockpit in the first place?
If you really feel that things can be handled better, let the pilot land, before you bring down the axe.
Too many lives are at stake and turbulence happens, independent of competence, capacity or character.
And do not forget that how you treat this pilot will dictate the commitment, courage and care incoming pilots will demonstrate.
Pilots can be changed, but turbulence always comes back, sooner or later.
Let them land the plane.
– Osasu Oviawe