Fuel Flow is the rate of consumption by the engine measured in pounds per hour

• The thrust required curve represents the amount of thrust necessary to equal the planes total drag during equilibrium flight
• There are no difference between the L/DmaxAOA and corresponding values between the power and the thrust curves unless there are changes made to the actual aircraft or the operating environment

Maximum Endurance is the maximum amount of time that an airplane can remain airborne on a given amount of fuel.

Maximum Range is the maximum distance traveled over the ground for a given

amount of fuel.

Angle of Climb (AOC) is a comparison of altitude gained to distance traveled (max altitude inc to min distance traveled)

Rate of Climb (ROC) is a comparison of altitude gained relative to the time needed to reach that altitude

T-34’s maximum operating ceiling is 25,000’ because it is not pressurized

Maximum Glide Range is when we need to glide as far as possible to reach a safe landing area

Maximum Glide Endurance is when we need to stay in the air longer while a runway is being cleared

• It is found at L/Dmax velocity and the AOA is greater than L/DmaxAOA
• The T-34 max glide endurance is found at 87 KIAS, with 100KIAS being used as the emergency landing pattern speed
• If altitude is increased, the max glide endurance will increase
• Wind will not effect the max glide endurance

• To changes from maximum glide range to maximum endurance, you must increase the AOA to a value greater than L/Dmax which equates to a minimum Power Required deficit
• For an aircraft to glide at a constant AOA L/Dmax, as the aircraft descends, the TAS must remain constant

Windmilling is when you have no engine power and you leave the blades flat to the relative wind and will significantly increase the drag of the aircraft. You must feather them into the wind (feathering the propeller).

Normal Command is velocity above maximum endurance that have airspeed stability

Reverse Command is velocity below maximum endurance that have airspeed instability. If you are at normal command, you will stay there with any increase or decrease in the planes airspeed. If you are at reverse command, a decrease in power would lead to a stall while an increase would lead to a normal command setting

- It is caused by increased induced drag with decreasing velocity

Aerodynamic Balance is used to keep control pressures within reasonable limits. Ie, when the trailing edge of the control surface is deflected in one direction, the leading edge deflects into the airstream forward of the hingeline.

Mass Balancing is a way to gain a balance between control response and stability. The T-34 control center of gravity’s are located on the hingelines. To locate the CG on the hingeline, weights are placed inside the control surface in the area forward of the hingeline (shielded horn and overhang)

Conventional Controls are the forces applied to the stick and rudder pedals that are transferred directly to the control surfaces via push pull tubes, pulleys, cables and levers. If an external force moves the control surface, the stick or rudder pedal will move in the cockpit. This action is called reversibility and gives the pilot feedback

Power Boosted Controls have mechanical linkages with hydraulic, pneumatic or electrical boosters to assist the pilot in moving the controls in the same way power steering assist a car’s driver

Full Power or Fly by Wire control system, the pilot has no direct connection with the control surfaces. Feel is only provided by Artificial Feel means. These devices create or enhance control feedback under various flight conditions

Stability is the tendency of an object to return to its state of equilibrium once disturbed from it

Static Stability is the initial tendency of an object to move toward or away from its original equilibrium

Dynamic Stability is the position with respect to time, or motion of a no object after a disturbance

Positive Static Stability is when an object has an initial tendency toward its original position after a disturbance. Negative Static Stability is for its initial movement to be away from equilibrium. Neutral Static Stability is when the initial tendency to accept the displacement position as a new equilibrium

Positive dynamic stability an object oscillates across the equilibrium till it finally settles back at the original equilibrium through damped oscillation.

Neutral dynamic stability: an object moves about the equilibrium position but the oscillations never dampen out

Negative dynamic stability: an object moves across equilibrium but at a greater distance with each pass and will never return to equilibrium and is described as having divergent oscillation

• Static stability does not endure dynamic stability, but Static instability ensures dynamic instability

Stable the displacements from equilibrium will be reduced until the object is again at its original equilibrium

Unstable is if the displacement may or may not increase, but the object never returns to its original equilibrium

Maneuverability is the ease with which an airplane will move out of its equilibrium position. It is opposite of stability. The more maneuverable an aircraft is, the easier it departs from equilibrium, but the less likely it is to return to equilibrium

• If a component’s aerodynamic center is behind the airplane’s CG, the component will be a positive contributor to longitudinal stability
• If a component’s aerodynamic center is in front the airplane’s CG, the component will be a negative contributor to longitudinal stability
• The wings of most aircraft are negative contributors to longitudinal static stability (ie straight wings)
• Sweeping the wings back is a positive contributor to longitudinal static stability
• The fuselage is a negative contributor of longitudinal stability
• The horizontal stabilizer will have the GREATEST positive effect on longitudinal stability because its moment is so far behind the CG

Neutral Point is the location of the center of gravity, along the longitudinal axis, that would provide neutral longitudinal static stability. It is the aerodynamic center for the whole plane

Sideslip is when an airplane yaws, its momentum keeps it moving along its original flight path for a short time

Sideslip Angle b is the angle between the longitudinal axis and the relative wind

Sideslip Relative Wind is the component of the relative wind that is parallel to the lateral axis

• Straight wings have a small positive effect on directional stability
• Swept wings will further increase directional stability
• Fuselage is a negative contributor to the directional stability
• The vertical stabilizer is the GREATEST positive contributor to directional stability of a conventionally designed airplane
• Dihedral wings are the GREATEST positive contributor to lateral static stability. Anhedral wings are the GREATEST negative contributor to lateral static stability
• A high mounted wing is a positive contributor and a low mounted wing is a negative contributor to lateral static stability
• Swept Wings are laterally stabilizing

Directional Divergence is a condition of flight in which the reaction to a small initial sideslip results in an increase in sideslip angle. Directional divergence is caused by negative directional static stability

Spiral Divergence occurs when an airplane has strong directional stability and weak lateral stability

Dutch Roll is the result of strong lateral stability and weak directional stability

Phugoid Oscillations are long period oscillations (20 to 100 seconds) of altitude and airspeed while maintaining a nearly constant AOA

Proverse Roll is the tendency of an airplane to roll in the same direction as its yawing. When an airplane yaws, the yawing motion causes one wing to advance and the other to retreat.

Adverse Roll is the tendency of an airplane to yaw away from the direction of the aileron input.

Asymmetrical Thrust is any airplane with more than one engine can have directional problems if an engine fails. The thrust from the working engines will create yawing moment towards the dead engine

Slipstream Swirl is the propeller imparted corkscrewing motion to the air. This air flows around the fuselage until it reaches the vertical stabilizer where it increases AOA. When a propeller driven airplane is at high power setting and low speed, the increased AOA creates a horizontal lifting that pulls the tail to the right and causes the nose to yaw left

Propeller Factor (P-Factor) is the yawing moment caused by one prop blade creating more thrust than the other. If the relative wind is above the thrust line, the up-going propeller blade on the left side creates more thrust since it has a larger AOA with the relative wind. This will yaw the nose to the right. If the relative wind is below the thrust line, such as in flight near stall speed, the down going blade is below the thrust line, the down going blade on the right side will create more thrust and yaw the nose to the left

Gyroscopic Precession is based on the properties of spinning objects. When a force is applied to the rim of a spinning object, parallel to the axis of rotation, a resulting force is created in the direction of the applied force, but occurs 90 degrees in the direction of rotation. Pitching the T-34 up produces an applied force acting forward on the bottom of the propeller disk. The resulting force would act 90 degrees ahead in the direction of propeller rotation (clockwise) and cause the plane to yaw right

Spin is a aggravated stall that results in Autorotation

Autorotation is a combination of roll and yaw that propagates itself and progressively gets worse due to asymmetrically stalled wings

-

Altimeter rapidly decreasing, Airspeed 80-100kts, AOA 30 units pegged, Turn Needle in the direction of spin (110-170 degrees per second)

- T-34 will not enter flat spins

Progressive Spin if upon recovery you put in full opposite rudder but inadvertently maintain full aft stick, the plane will begin autorotation in the opposite direction

Aggravated Spin results from pushing the stick forward while maintaining rudder in the spins direction, it ends up being an extreme case of an accelerated spin.

1. Landing gear and flaps up
2. Verify spin indication by checking AOA, airspeed, and turn needle
3. Apply full rudder opposite of turn needle
4. Position stick forward of neutral
5. Neutralize controls as rotation stops
6. Recover from ensuing unusual attitude

- The horizontal control surface deflects the relative wind towards or away from the vertical stabilizer

Load Factor is the ration of total lift to the airplane’s weight and is sometimes called g’s

Accelerated Stall Speed because it represents the stall speed at velocities greater than minimum straight and level stall speed, and load factors greater than one

• Stall speed increases when we induce a load greater than one on the airplane

Load is a stress producing force that is imposed upon an airplane or component

Strength is a measure of material’s resistance to load

Static Strength is a measure of a material’s resistance to a single application of a steadily increasing load or force

Static Failure is the breaking of a material due to a single application of a steadily increasing load or force

Fatigue Strength is a measure of a material’s ability to withstand a cyclic application of load or force

Fatigue Failure is the breaking of a material due to cyclic application of load or force

Service Life is the number of applications of a load or force that a component can withstand before it has a probability of failing

Creep is when a metal is subjected to high stress and temperature it tends to stretch or elongate

Limit Load Factor is the greatest load factor an airplane can sustain without any risk of permanent deformation (the maximum load factor in normal daily operations)

The T-34’s limit factors are 4.5 to –2.3 G’s

Overstress/Over-G’s is the condition of possible permanent deformation or damage that results from exceeding the limit load factor. These actions reduce the service life of an aircraft because they weaken the airplane’s basic structure. ALWAYS report an overstress/over G to maintenance, visually inspect the aircraft in the air and inspect it upon reaching the ground

Elastic Limit is the maximum load that may be applied to a component without permanent deformation.

Ultimate Load Factor is the maximum load factor that the airplane can withstand without structural failure. There will be some permanent damage deformation at this point. If you exceed the ULF, structural failure is imminent. It is usually 150% of the limit load factor

• If a metal is affected by low values of applied stress, the metal will incur no permanent deformations and the material will return to its original unstressed shape when the stress is released

V-n/G Diagram is a graph that summarizes an airplane’s structural and aerodynamic limitations. It is a plot of IAS vs the Load Factor

Accelerated Stall Lines represent the maximum load factor that an airplane can produce based on stall speed and are determined by ClmaxAOA.

Maneuvering Point is the point where the accelerated stall line and the limit load factor line intersect. The IAS here is called Maseuver Speed (Va) or cornering velocity. It is the lowest airspeed at which the limit load factor can be reached.

The T-34s maneuver speed is 135 KIAS.

Redline Speed is the vertical line on the right side of chart and is the highest airspeed that your plane is designed to fly Vne is determined by Mcrit, airframe temperature, excessive structural loads, or controllability limits

Excessive horizontal stabilizer loads can be encountered in the T-34 at speeds in excess of 280 KIAS

Aileron Reversal is caused by exceeding the Vmax of the aircraft

Safe Flight Envelope is the portion of the V-n Diagram that is bounded by the accelerated stall lines, the limit load factor and the redline speed. It is affected by gross weight, altitude, configuration, asymmetrical loading, and gust loading

• If an airplane’s weight decreases by burning fuel or expending ordinance, the limit load will increase
• If altitude increases, the indicated redline airspeed must decrease in order to keep a subsonic airplane below Mcrit. Above 20000 feet, the T-34s redline airspeed decreases to 245 KIAS
• The safe flight envelope is affected by the configuration. With flaps, landing gear or canopy open, the redline speed decreases
• The primary danger in flying between the maneuver speed and the redline speed in turbulent air is overstress

Asymmetrical Loading refers to the uneven production of lift on the wings caused by rolling pullout, trapped fuel, or hung ordinance. Because asymmetric loading is cumulative with pilot induced loading, the limit factor due to pilot induced loads should be reduced by 2/3 of the normal load limit. In the T-34 the maximum load factor during asymmetric loading is 3 G’s

NATOPS states that the maximum airspeed for the T-34 in moderate turbulence is 195 KIAS.

Turn Rate f is the rate of heading change, measured in degrees per second

Turn Radius (r) is a measure of the radius of the circle the flight path scribes

• If velocity is increased for a given angle of bank, turn rate will decrease, and turn radius will increase
• If angle of bank is increased for a given velocity, turn rate will increase and turn radius will decrease
• Turn rate and radius are independent of weight

Skid is caused by using too much rudder in the desired direction of turn. The yawing movement is toward the inside of the turn and the balance ball is defelcted toward the outside to centrifugal flow. In a skid, turn radius will decrease while turn rate will increase. Skids are dangerous because the plane will roll inverted if stalls occur

Slip is cause by insufficient rudder in the desired direction of the turn. In a slip, turn radius increases while the rate decreases

• If an airplane increases its bank, it will need to increase its total lift and true power on stall speed to remain at constant altitude
• Making turns at the maneuver airspeed is the best trade off between getting the smallest radius turn while achieving the best rate of turn for a given aircraft

Rolling Friction Fr accounts for the affects of friction between the runway surface.

• Factors that determine minimum landing distance are weight, velocity, thrust, drag, and rolling friction
• Weight is the greatest factor in determining takeoff distance
• Three factors decreasing density: elevation, humidity and temperature

4-H’s that refers to the high, hot, humid and heavy. They present the worst conditions to takeoff or land in because the distance can be so greatly increased

• Upon using high lift devices, the decreased will be seen in takeoff distance because they decrease both the indicated and true takeoff speeds
• A head wind will decrease the takeoff distance by reducing the ground speed associated with the takeoff velocity
• During landing, the primary consideration is the dissipation of KE which ends up being Fr+D-T with Friction being Desirable
• As weight increase, so will landing and takeoff distance
• An increase in elevation, temperature or humidity will increase landing distance
• High lift devices decrease landing distances
• A headwind reduces landing distances because it reduces ground speed
• An increase in density will decrease the take off distance

Aerodynamic Breaking is accomplished by increasing the parasite drag on the airplane by holding a constant pitch attitude after touch down and exposing more surface to the relative wind. Drag Chutes, Spoilers, Speed Breaks are additional examples. It is used at the beginning of the landing roll to save the breaks later on and is the most efficient

Mechanical Breaking is effective only after enough weight is transferred to the wheels and the airplane has sufficiently slowed and is done through large disk breaks on the wheels

Beta breaking is when you use reverse thrust off the propeller pitch to shorten the landing roll. This thrust greatly decreases the net decelerating force

Ground Effects is a phenomenon that significantly reduces induced drag and increases effective lift when the airplane is within one wingspan of the ground.

• The downwash at the trailing edge of the wind is unable to flow downward because of the surface, thus adding to the planes total lift
• As an airplane takes off and leaves the ground effects, induced drag increases and lift decreases
• Entering ground effect (during landing) increases effective lift and decreases induced drag, but total lift remains constant

Hydroplaning causes the airplane’s tires to skim atop a thin layer of water on the runway

Wingtip Vortices are spiraling masses of air formed at the wingtips when an airplane produces lift. Flying into vortices may instantly change the direction or the relative wind and cause one or both wings of the trailing plane to stall or disrupt airflow in the engine inlet inducing a compressor stall

• It is very difficult for planes with short wing spans to counter the imposed roll of wingtip vortices
• The most significant factor affecting your ability to counteract the roll is the relative wingspan between the two planes
• Vortices are generated from the moment an airplane rotates for takeoff tell the nose wheel touches down for landing
• The greatest vortex strength occurs when generating airplane is Heavy, Slow and Clean. Weight is the most significant factor in the strength of wingtip vortices
• The most important pilot technique for survival during wake turbulence is to avoid it!
• When landing behind a large airplane, stay at or above the larger planes final approach path and land beyond its touchdown point
• Ensure that an interval of at least two minutes has elapsed before conducting a takeoff after a larger plane has landed
• If taking off after a large plane, ensure that your landing or takeoff rotation is before the large planes point of rotation
• Small airplanes should avoid operating within three rotor diameters of any hovering helo

Wind Shear is defined as a sudden change in wind direction and/or speed over a short distance. It is most often caused by jet streams, land or sea breezes, fronts, inversions and thunderstorms

• Wind shear can be very complex combinations of wind velocities and as they become complicated require the pilot more difficulty to correct
• May change the airflow over the aircraft. The velocity of the relative wind can be altered causing immediate changes in the indicated airspeed and/or AOA
• During landings and takeoffs, wind shear can become very dangerous
• Look at wind shear situations in the book
• Notice wind shears thru virga, localized dust blowing, rain shafts diverging from the core of the cell, and lightning of tornado like activity
• Head winds are the best for takeoff and landings!
• If density altitude increase, takeoff velocity increases and the thrust and net acceleration force decrease