Experiencedly learned we can say that people on a plane like to clap for a variety of reasons. Most often people applaud after a flight they have experienced as dangerous due to frequent and intense turbulence, especially if all of this has been accompanied by a sense of sudden decay and scenes of turbulent weather through the aircraft window. But there are also situations when people applaud because they are simply happy to have arrived at a popular holiday destination or to have returned home after a long time. Also, there are situations when there are just a lot of happy people who met on the aircraft, so they concluded the party on the flight with applause. What is common to most situations where passengers choose to clap is that the sound of palm-to-palm strikes follows a moment after the aircraft touches the ground with its wheels.
But the question is can the pilots hear you?
There are several factors that can affect whether pilots will hear you or not as you clap. Some of the factors relate to the type of aircraft and its construction, i.e. how far the cockpit is from the passengers and the degree of sound insulation that the cockpit doors provide. Of course, passengers also have a significant impact on the applause, and the volume of applause will depend on the number of passengers and the intensity of the applause.
But most likely the success of the applause will depend on the noise level in the cockpit caused by the use of reversible thrust. So, the higher the intensity of the use of reversible thrust, the louder the noise in the cockpit itself. For pure explanation, reversible thrust is the redirection of the thrust of an aircraft engine in the opposite direction from the direction of forward movement of the aircraft. Reversible thrust enables fast deceleration, i.e. sudden deceleration of the aircraft and reduction of the runway length, as well as less brake wear. Also, reversible thrust is used to reverse the aircraft, for example in case of powerback. We have already written about this powerback, so you can remind yourself of it on the link below.
Given all of the above, we can answer that pilots can generally passengers clapping. Of course, there are also situations and factors that can prevent pilots from hearing you as you clap, in which case pilots will find out that you clapped only if they are notified by cabin crew.