Aerospace Engineering and Turning Forces - Essay Example

Your name:   Student Number: Title:         Turning Forces Figure 1. Forces during normal coordinated turn (Atluri, 2010) Newton’s Law of Inertia, First Law of Motion, states that an object in motion in a straight line or at rest continues to move in a straight line or remains at rest until acted on by some other force. An aircraft or airplane, like any moving object, requires forces acting on the sides to make it spin or turn. In a normal turn in an aircraft, these side forces are supplied by banking the aircraft so that lift is exerted upward, as well as inward (Atluri, 2010) . The forces in lift during a turn are divided into two components at right angles to each other. One component, which acts horizontally toward the center of the turn, is known as centripetal force, or “horizontal component of lift,” The other, which acts vertically and opposite to the gravity (weight), is known as the Centrifugal force or “vertical component of lift.” The force that pulls the airplane from a straight line or flight path and makes the airplane to turn is the horizontal component of lift. The vertical component of lift or centrifugal force which produce “equal and opposite effect or reaction,” makes the aircraft to change its direction and acts equal and opposite to centripetal force, or “horizontal component of lift.” In a correctly executed turn in an aircraft, the force that turns the aircraft is not supplied by the aircraft rudder. But the work of the rudder is to correct any deviation between the straight track of the tail and nose of the airplane. A good turn in an airplane is one which the tail and nose track along the same path in an airplane. Therefore, the work of the rudder in an airplane is to bring the nose back in line with the relative wind that acts on the airplane. Figure 2. Normal, slipping, and skidding turns (Atluri, 2010) At any given speed, the rate at which the airplane turns will depend on the magnitude of centripetal force, or “horizontal component of lift,” and is proportional to the angle of bank. As the angle of bank is increased, the centripetal force, or “horizontal component of lift increase, thus increasing the ROT (Tooley and Dingle, 2011). Consequently, the ROT can be controlled by adjusting-increasing or reducing- the angle of bank. To provide Centrifugal force or “vertical component of lift.” sufficient to hold altitude in a level turn, an increase in the AOA is required (Atluri, 2010). Turning Manoeuvres If an airplane turns (banks), the lift vector in the aircraft will be tilted and made to turn. When an airplane turns in any plane, an additional pressure or force in the aircraft must be continuously be applied to overcome the inertia that happening in the aircraft, particularly it is the tendency for an aircraft to continue moving in a straight line. Some of the lift will act on the aircraft horizontally (Tooley and Dingle, 2011). In order for the aircraft to maintain its altitude, the aircraft is required to increase the lift on the wings. And this is done when the aircraft angle of attack of the wings (pulling back on the stick) is increased or decreased. But if the aircraft speed is allowed to drop below the stalling speed, In most cases the wings of the aircraft will stop producing necessary lift (stall) and if the aircraft is too low from the ground to recover, it may turn into a disaster (such as it may crash) (Tooley and Dingle, 2011). Another way which a crash can occur is when the aircraft loose it lateral stability and this will cause the airplane to enter a spin or skid. The lateral stability in the aircraft is affected ont only by the gear design of the aircraft, such as its tyre and geometry characteristics, but also operational characteristics of the aircraft such as the taxiway and weather condition. Navigation Instruments 1. Charts and Maps Aviation charts mark is an important aviation landmark such as airports and airspace boundaries. The work of automatic charts and maps are used to display objects or things on ground that pilots in aircrafts can use as a guide to navigation. The charts and maps range in detail and scale, such as for approaches into airports or long distance navigation. Many of these charts and maps, such as sectional charts, include important information such as frequencies for navigational aids called VORs and airport tower frequencies. 2. Weather Reports This equipment is mostly overlooked part of aircraft navigation, weather reports play an important role in the planning of a route (Klemin and Henri, 2006). A pilot will be assisted by weather forecast conditions along his planned route, and this will range from winds to cloud cover in the air and on the ground (Klemin and Henri, 2006). Therefore, using the reports of weather forecast, a pilot is able to plan her route around bad weather in addition to calculating the direction of air at different heights or altitudes and how it will affect the overall flight path of the aircraft (Klemin and Henri, 2006). 3. E6B Flight Computer Most aircrafts used the E6B flight computer, also known as whiz wheel, to perform many calculations in the air and on the ground. This slide rule-type calculator uses a sliding mechanism and rotatable wheel (Klemin and Henri, 2006). It allow a pilot in an aircraft to perform many calculations, including aircraft ground speed along a route of the aircraft, the amount of fuel needed to complete a journey and amount of fuel needed. And, heading the aircraft needs to fly to correct for wind that pushes the aircraft off course (Klemin and Henri, 2006). 4. Global Positioning System With the help of satellite navigation via GPS (Global Positioning System), GPS receivers make it easier for aircraft to navigate during the flight (Hephaestus 2011). A pilot with the help of GPS (Global Positioning System) can be able to plot a direct route the aircraft will follow from one location to another, instead of following traditional ground-based navigation aids (Klemin and Henri, 2006). GPS equipment also helps the pilot to know if he/she being blown off course or the pilot will know if he/she flying in the wrong direction and give him enough time to correct the direction in which he is supposed to fly to without the use of a sectional chart or calculations. Nowadays, GPS equipment automatically calculates an aircraft’s ground speed and heading Hephaestus, 2011). Factors that contributed to aircraft crashing while turning 1. Investigation Number: 199701568 When the accident happened there was no recorded flight data or any witnesses. The factors leading to the aircraft accident could not be easily determined. However, the right turn indicated the aircraft destination was northeast, into the near valley and the aircraft attempted to turn back down the valley. It is possible the accident was caused by turbulent conditions found in the mountain valley that affected the climbing performance of the affected aircraft. And the disturbance at the mountain valley was enough to create doubt in the pilot’s judgment that the aircraft had enough residual performance to out-climb the mountain valley floor. Another reason that contributed to the accident was that the Cloud at the mountain valley affected the visibility and delayed or limited the pilot’s appreciation of the mountain terrain which was new to the pilot. Similarly, if the mountain valley was clear, the azimuth and elevation of the sun relative to the airplane track may also have caused the pilot misjudge the valley terrain ahead. All these possibilities mentioned above may have caused the pilot to turn back. 2. Investigation Number:200506306 The absent of emergency radio broadcast, and witnesses to the accident meant there was no information which was available to the investigation about the aircraft situation prior to the aircraft accident. However, prior to the accident, the pilot was consistent in communication with a four wheel drive vehicle, and at same time he was attempting to disturb the sheep from their position. Possible cause of the accident was that the lack of aircraft rotation at impact indicated that there had been insufficient time for the stall to develop into a spin, consistent with it occurring at low level. This means the pilot of the aircraft had insufficient time to recover before the aircraft impacting the ground. The pilot was focused on how he could shelter the sheep; together with the need to operate the aircraft’s UHF radio may have distracted the pilot from appropriately controlling the aircraft. In addition, sensory illusion on the part of the pilot as a result of him moving his head during inadvertent movement of the flights controls or low-level maneuvering could have made the pilot to increase the aircraft’s angle of bank. Finally, the engine developed mechanical problems and this is due to damage to the aircraft’s propeller, but the aircraft had enough fuel and the pilot had flown the aircraft for less than 1.5 hours. 3.  Investigation Number:200204663 According to eye witnesses, the aircraft (C182) was flying at a lower altitude, and its wings were rocking from side to side, this was consistent with the turbulence that was produced by strong wind coming from the lee side of the escarpment. With the strong winds it could have required a skilled pilot to fly the aircraft to safety. Therefore, the possible cause of the accident was the aircraft landing approach was unstable in the turbulence with airspeed fluctuations. Additionally, the pilot turned the aircraft where there was increased turbulence. Additionally, the direction of turn was consistent also with the pilot turning away from the glare of the setting sun. References Atluri, N. (2010). Computational nonlinear mechanics in aerospace engineering. New York: American Institute of Aeronautics and Astronautics Hephaestus, B. (2011). Articles on Aerospace Engineering, Including: Aerodynamics, Global Positioning System, Spacecraft Propulsion, Wing, Hypersonic, Skunk Works, Chord (Aircraft), Supersonic, Aeroelasticity, Aerospace Manufacturer, Aircraft Parts Industry. London: Taylor & Francis Publisher Klemin, A and Henri,T. (2006). Aeronautical Engineering and Airplane Design. New York: Gardner-Moffat Company Tooley, M and Dingle, L. (2011). Aircraft Engineering Principles. London: Taylor & Francis Publisher. Read More