Icing

Aircraft Accident Investigation
Aerodynamics and Icing Effects

Power Point by D. Johnson ERAU

Aircraft Performance, Icing, Stability, and Control
Determining Aircraft Performance
• • • Itmay be necessary for accident investigators to reconstruct the final maneuvering performance of an aircraft. In order to perform the calculations necessary for such an analysis, a high degree oftraining and experience is required. Some of the subjects addressed in an analysis of this nature are:
– – – – – – – – Forces acting on maneuvering aircraft. Turn radius. Rate of Turn. Aerodynamics.Kinetic & Potential energy factors. Vertical and Horizontal Velocity. Interaction between various “G” forces. Rates of acceleration and deceleration.

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Complicated calculations, thorough knowledge ofaerodynamics, and some experience (at the very least) may be needed for the reconstruction process.
Power Point by D. Johnson ERAU

Aerodynamics Review

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Lift Weight Thrust Drag

Allforces are equal in: Level Flight Stabilized Climb Stabilized Descent

Power Point by D. Johnson ERAU

Aerodynamics Review

Power Point by D. Johnson ERAU

Aerodynamics Review: Lift
Liftwas discovered by Italian scientist Bernoulli who determined that a liquid flowing through a restricted area tends to increase in speed as it passes through the restricted area of the tube. Bernoullialso discovered that a pressure change occurs as the liquid passing through the restriction increased in speed. Air is a liquid and reacts in the same manner. As air passes over a curved surface, theair increases in speed to catch the air flowing on the underside of the surface when the air masses again meet. The upper surface of a wing is curved to cause a delay in the air flowing over the top ofthe wing versus the air flowing under the wing. The delay forces the air to increase in speed and creates a low pressure system on the top of the wing. The air on the bottom of the wing travels at...