# Relationship of lift drag thrust and weight

### The Four Forces | How Things Fly

These forces are called thrust, drag, lift, and weight. Thrust is the forward force that pushes the plane along the runway and forwards through the sky. Drag is the . Weight has a definite relationship with lift, and thrust with drag. These relationships are quite simple, but very important in understanding the. Computer drawing of an airliner showing vectors for lift, thrust, drag and weight. A force may be thought of as a push or pull in a specific direction. A force is a.

Aviation Seminars 26 Sorry that is Incorrect. Next Question Aviation Seminars 28 The angle of attack at which an airplane wing stalls will A- increase if the CG is moved forward.

### The 4 Forces of Flight

B- change with an increase in gross weight. C- remain the same regardless of gross weight. Aviation Seminars 29 Sorry that is Incorrect. Next Question Aviation Seminars 31 Next Question Aviation Seminars 34 What is one purpose of wing flaps?

A- To enable to pilot to make steeper approaches to a landing without increasing airspeed. B- To relieve the pilot of maintaining continuous pressure on the controls.

C- To decrease wing area to vary the lift. Aviation Seminars 35 Sorry that is Incorrect. Next Question Aviation Seminars 37 Which aileron positions should a pilot generally use when taxiing in strong quartering headwinds?

A- Aileron up on the side from which the wind is blowing. B- Aileron down on the side from which the wind is blowing. Aviation Seminars 38 Sorry that is Incorrect. Next Question Aviation Seminars 40 While taxiing a light, high-wing airplane during strong quartering tailwinds, the aileron control should be positioned A- neutral at all times.

### Theory of Flight

B- toward the direction from which the wind is blowing. C- opposite the direction from which the wind is blowing.

• The Four Forces
• Thrust and Drag

Next Question Aviation Seminars 43 Longitudinal dynamic instability in an airplane can be identified by A- bank oscillations becoming progressively steeper. B- pitch oscillations becoming progressively steeper. C- Trilatitudinal roll oscillations becoming progressively steeper. Aviation Seminars 44 Sorry that is Incorrect. Next Question Aviation Seminars 46 How should the flight controls be held while taxiing a tricycle-gear equipped airplane into a left quartering headwind? A- Left aileron up, elevator neutral.

B- Left aileron down, elevator neutral. C- Left aileron up, elevator down. Aviation Seminars 47 Sorry that is Incorrect. Next Question Aviation Seminars 49 The reason for variations in geometric pitch twisting along a propeller blade is that it A- permits a relatively constant angle of incidence along its length when in cruising flight. B- prevents the portion of the bade near the hub from stalling during cruising flight. C- permits a relatively constant angle of attack along its length when in cruising flight.

Aviation Seminars 50 Sorry that is Incorrect. Next Question Aviation Seminars 52 When does P-factor cause the airplane to yaw to the left? A- When at low angles of attack. B- When at high angles of attack. C- When at high airspeeds. Aviation Seminars 53 Sorry that is Incorrect. Next Question Aviation Seminars 55 One purpose of the dual ignition system on an aircraft engine is to provide for A- improved engine performance.

## Class Discussion

B- uniform heat distribution. C- balanced cylinder head pressure. Aviation Seminars 56 Sorry that is Incorrect. Next Question Aviation Seminars 58 How is engine operation controlled on an engine equipped with a constant-speed propeller?

A- The throttle controls power output as registered on the manifold gauge and the propeller control regulates engine RPM.

B- The throttle controls power output as registered on the manifold pressure gauge and the propeller control regulates a constant blade angle. C- The throttle controls engine RPM as registered on the tachometer and the mixture control regulates the power output.

Aviation Seminars 59 Sorry that is Incorrect. Next Question Aviation Seminars 61 If the ground wire between the magneto and the ignition switch becomes disconnected, the most noticeable result will be that the engine A- will not operate on the left magneto. Next Question Aviation Seminars 64 In aircraft equipped with constant-speed propellers and normally-aspirated engines, which procedure should be used to avoid placing undue stress on the engine components?

Back to page one In level flight, lift equals weight and thrust equals drag when the plane flies at constant velocity. Maintaining a steady flight requires a balance, often described as an equilibrium of all the forces acting upon an airplane. Weight, lift, thrust and drag are the acting forces on an airplane.

Assuming a straight and level flight, lift must be equal to weight and drag must be equal to thrust. This is what happens if this equilibrium is violated: If lift becomes greater than weight, then the plane will accelerate upward. If the weight is greater than the lift, then the plane will accelerate downward. When the thrust becomes greater than the drag, the plane will accelerate forward. If drag becomes greater than the thrust a deceleration will occur.

Acceleration is best explained by using Newton 's Second Law of Motion. The proportion between weight and thrust is determined by the airplane designer depending on the anticipated missions.

For example, if by design an airplane must be able to accelerate vertically upwards then the thrust must be greater than the weight and drag combined. The engine creates thrust and moves the plane forward. Gravity provides the thrust for a glider.