Aircraft Systems and Flight: The importance of the Pitot-Static System

 Pitot-Static System (by  Diego Llorente) 

                              The human being is composed of systems that contain organs. Airplanes are also composed of systems that contain fundamental elements for the performance and proper operation of the airplane. In the previous blog, I mentioned the importance of performance and every pilot must have knowledge of those details. By the way, every pilot must know how an airplane is composed, its systems and how each one of them works. One can find several systems such as the fuel system, the electrical system, and many others. In this case, my example is directly connected with the Cessna 172. An aircraft widely used for pilot training and contains, like all aircraft, a system that I consider the relevant system to be analyzed and considered for every pilot worldwide, the pitot-static system.

                              Engine operation, fuel system, and landing gear are unquestionably important, the pitot-static system is not the exception because you can find it from a C172 to the A380. What does this system deal with? How does it work?

 

                                  The pitot-static system is a pressure-based system. It is responsible for measuring and comparing air pressure and static pressure. On the other hand, it deals with reflecting data that is very important for the flight and reflects in a certain way part of the current performance of an aircraft. The data obtained is transmitted through the aircraft instruments located in the cockpit, which provides the pilot with information on the altitude, airspeed, and vertical speed of the aircraft. The pitot-static system includes a few components such as a pitot tube and static port. The pitot-static is usually located on the wing of the airplane and the static port is attached to the airplane’s fuselage.

                                  As mentioned, this system provides essential information for a pilot located in the cockpit regarding the speed, height, and height variation of the aircraft. If a blockage of this system or failure occurs, the information would be erroneous and could cause serious consequences to the flight, possible misinterpretation and not being able to identify an error or failure. It is very important that a pilot is familiar with its operation and possible failures-errors.

                                  As I said in the previous paragraph, this system provides essential information about airspeed, altitude, and vertical speed. A failure or a blockage could affect several instruments that are essential to developing a flight. I take as an example the Cessna 172 for the essential training and flights that a pilot performs. Commercial aircraft have a digital instrument called EFD (Electronic Flight Display) that has an integration of the systems that we can see in the C172. Now, if this system fails, the ones that will be used are the same analogs that are used in the Cessna.

                                   Pitot-static system obstructions can occur for several reasons. On land, the C172 must be covered over the pitot tube to prevent it from being blocked by insects or in low temperatures with ice particles. The control of this system in the pre-flight inspection is vital. There are different possible errors and obstructions. First, if the Pitot tube is blocked on its front for the reasons mentioned, for example, an insect blockage, this situation will cause the airspeed indicator to become zero. A clogged Pitot tube affects only the airspeed indicator. In the Cessna 172 being able to see the speed is essential to maintain margins when making a maneuver and/or approach and thus avoid entering a stall or spin. The airspeed indicator will not detect a difference between the pressures.

                                   On the other hand, an airplane can have several static ports and if these are obstructed the situation can be more serious since more instruments such as the airspeed indicator, the vertical speed indicator and the altimeter will be affected. In the C172 as in all airplanes that do not have an EFD, the airspeed indicator will continue to function but will not provide accurate information. Otherwise, the vertical speed indicator will not provide information, therefore it will be zero and the altimeter will freeze at the altitude at which the blockage occurred.

                                  In conclusion, it is very important that a pilot is familiar with this essential information, such as knowing the performance of the plane that is being flown. Having this knowledge of the possible failures and errors of the systems, in this case of the pitot-static system, will increase safety. All these flight instruments have redundancy to ensure safety in the event of system failure. It is important to mention that a pilot knows how to interpret this system to avoid an accident or incident, the presence of freezing or icing. It is important that a pilot knows everything that we have been mentioning in this blog and the previous ones because they make a pilot safe and trained.

 References

American Psychological Association. (2019). Publication Manual of the American Psychological Association: 7th Edition, 2020 Copyright (Seventh ed.). American Psychological Association

How It Works: Pitot-static system. (n.d.). Pitot-Static System. Retrieved August 15, 2021, from https://www.aopa.org/news-and-media/all-news/2018/november/flight-training-magazine/how-it-works-pitot-static-system

Theory, A. (2021, February 17). Pitot-Static System. YouTube. https://www.youtube.com/watch?v=mqLyitBTfjY&feature=youtu.be