Term
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Definition
| AKA wingtip vortices, WT is spiraling masses of air that are formed at the wingtip when an airplane produces lift. Diameter of the core is about 1/4 the generating aircraft's wingspan. They sink at a rate of 400-500 feet per minute and level off about 900 feet below the flight path. lose strength and break up after a few minutes. |
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Term
| Describe the effects of changes in weight, configuration and airspeed on wake turbulence intensity |
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Definition
Weight up, WT up.
Flaps down, WT down (increase chordwise/decrease spanwise).
Airspeed down, WT up
*Heavy, slow and clean is strongest WT time* |
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Term
| Describe the effects of wake turbulence on aircraft performance |
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Definition
| Creates induced roll. Short wings have more trouble countering this. Also induced flow field - interactions of both (strong downwash 1,500 feet per minute) |
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Term
| State the takeoff and landing interval requirements for the T-6B |
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Definition
Minimum takeoff spacing - 2 minutes for heavy and large AC
Minimum landing spacing - 3 minutes for heavy aircraft |
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Term
| Describe procedure for wake turbulence avoidance during takeoff |
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Definition
| Make sure to take off behind and climb above. 300 feet prior. If taking off after large aircraft landed, take off forward of the point where first AC's nosewheel touched the ground. Also be careful on parallel runways. |
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Term
| Describe procedure for wake turbulence avoidance during landing |
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Definition
| Make sure to land in front and above. if it has just taken off, make sure you touchdown prior to larger aircraft's rotation point. Also be careful on parallel runways. |
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Term
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Definition
| Sudden change in wind direction and/or speed over a short distance in the atmosphere |
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Term
| State conditions that will lead to an increasing performance wind shear |
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Definition
| If faster headwinds are blowing at a level above ground on takeoff, or below a level on landing, you will instantly experience more lift and IAS at that height |
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Term
| State conditions that will lead to a decreasing performance wind shear |
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Definition
| If faster tailwinds or significantly less headwind happen above a level on takeoff or below a level on landing, will experience a drop in IAS and altitude quickly. |
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Term
| Describe the effects of wind shear on aircraft performance |
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Definition
| Can disrupt normal takeoff and landing operations (especially DP WS on landing). Can abruptly cause change in AC performance. Most dangerous in slow and low speeds and altitudes. With ample AS and ALT does not cause a problem. |
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Term
| Describe procedures for flying in and around wind shear |
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Definition
Consider going around, especially if moderate or strong. Avoid microbursts at all costs. If experiencing instant jump in lift, apply power to fly through the microburst. Watch for visual cues like virga, localized blowing dust and rain being blown away.
Takeoff: use long runway, use flaps but delay rotation by amount of WS, climb and maintain at faster speed, and abort if encountered near rotation speed. |
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Term
| Describe wind shear avoidance techniques |
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Definition
| Watch LLWAS and NEXRAD indications. Look for visual cues. go around. consider diverting if necessary. |
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Term
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Definition
| An aggravated stall that results in autorotation. For a spin to occur, stall and yaw must be present. |
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Term
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Definition
| A combination of roll and yaw that propagates itself due to asymmetrical stalled wings. |
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Term
| Describe aerodynamic forces affecting a spin |
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Definition
| Need unbalanced lift and drag in a stall; roll causes down-going wing to be more stalled. on down-going wing, higher AOA, less lift and more drag. Opposite for up-going wing. Differential lift continues rolling motion around spin axis (through cockpit on T-6B). Increased AOA on down wing also increases drag and produces yaw around spin axis. |
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Term
| State characteristics of erect, inverted and flat spins |
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Definition
Erect spin - positive G stall entry. Upright. Turn needle is only accurate indication of spin direction
Inverted spin - characterized by inverted attitude and negative G's on airplane. Uncommon since vertical stabilizer causes airplane to recover easily. T-6B prohibited from intentionally entering this.
Flat spin - characterized by flat attitude and transverse Gs. Since RW directly below airplane, control surfaces are ineffective. indications similar to erect spin except airspeed can vary. T-6B cannot even do this |
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Term
| Describe factors contributing to aircraft spin |
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Definition
Spin axis relative to CG - nose down increases rate (reducing moment arm) and nose up decreases rate (spaces them out)
Ailerons - in direction of spin will increase roll and yaw. Opposite will dampen; however little useful wind flowing over them means they won't do much
Rudder - principal control for stopping spin. Creates drag to create opposite yawing moment. Drag can be divided into horizontal and vertical component. Horizontal reduces rotation, vertical pulls tail up and pitches nose-down, reducing AOA |
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Term
| Discuss effects of weight, pitch attitude and gyroscopic effects on spin characteristics |
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Definition
Heavier aircraft have slower spin entry with lesser oscillations. Lighter has larger oscillations and faster spin but recovers easier.
pitch attitude increases, vertical lift increases, stall speeds slower and less oscillations. Low pitch attitudes, stalls at higher airspeed and enters faster with more oscillations
gyroscopic procession - right spin T-6B pitches down; left spin, pitch up (flatter). smoother, slower in left. faster and oscillations increase right (down) |
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Term
| State how empennage design features change spin characteristics |
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Definition
| swept vertical fin - airflow blocked to rudder, not as effective. Dorsal fin increases surface area, ventral fin decreases spin rate and maintains nose down. Strakes increase surface area of horizontal stabilizer to keep nose down. |
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Term
| State cockpit indications of an erect and inverted spin |
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Definition
erect spin - rapidly decreasing altimeter, KIAS 120-135, 18 AOA, turn needle pegged in direction of spin, VSI 6000fpm pegged
inverted spin - rapidly decreasing altimeter, KIAS 40, 0 AOA, turn needle pegged in spin direction, VSI 6000 fpm pegged |
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Term
| Describe pilot actions necessary to recover from a spin |
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Definition
| configuration clean, PCL Idle, rudder full opposite, stick forward/ailerons neutral, recover to level flight after autorotation stops |
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Term
| Describe a progressive spin |
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Definition
| full opposite rudder BUT full aft stick; plane starts spinning other direction, violently and disorienting. |
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Term
| Describe an aggravated spin |
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Definition
| pro-spin rudder with control stick forward of neutral. Can also use neutral rudder. steep nose-down attitude (70 degrees) and increase in spin rate (280 deg per second). Recover the same. |
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Term
| Define the boundary layer |
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Definition
| layer of airflow over a surface that demonstrates local airflow retardation due to viscosity |
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Term
| Describe the different types of flow within the boundary layer |
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Definition
Laminar flow - moves smoothly along surface but separates easily (first third)
Turbulent flow - breaks up, flow disorganized and irregular. Does not separate easily. |
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Term
| Describe boundary layer separation |
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Definition
| Favorable pressure gradient pushes air from leading edge along toward middle of wing. At the adverse pressure gradient, boundary layer will stagnate and separate. Need area with laminar flow and favorable pressure gradient in order to create lift |
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Term
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Definition
| The AOA beyond which a stall will occur. Separation point is too far forward to create lift. AKA Stalling or critical AOA. |
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Term
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Definition
| condition of flight in which an increase in AOA results in a decrease in CL (and hence lift). Stalls result in decreased lift, increased drag and loss of altitude |
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Term
| Explain how a stall occurs |
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Definition
| As angle of attack increases, speed decreases. When critical AOA is reached, air ceases to flow over the top of the wing, and lift stops being generated. Stall occurs immediately when exceeding CLMAX AOA |
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Term
| Identify aerodynamic parameters causing a stall |
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Definition
| Lift no longer equals weight and plane begins to drop. Drag is also large. |
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Term
| Compare power-on and power-off stalls |
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Definition
| Power-off stall has a higher stall speed. For power-on stall, part of the weight of the airplane is being supported by the vertical component of thrust |
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Term
| Describe order of losing control effectiveness approaching a stall in the T-6B |
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Definition
| Ailerons to elevator to rudder |
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Term
| Explain the difference between true and indicated stall speed |
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Definition
| True stall speed uses the local air density; indicated is based on sea level pressure so it is constant. TAS stall speed increases approximately 3 knots for every 1000 in feet |
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Term
| Explain the effects of gross weight, altitude, load factor and maneuvering on stall speed |
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Definition
Weight is proportional. Density, surface area and CLMAX are all inversely proportional.
Altitude will not affect indicated stall speed but will increase true stall speed.
High load factor can cause accelerated stall; maneuvering can cause one wing to stall first |
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Term
| State the purpose of using high lift devices |
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Definition
| Primary purpose - reduce takeoff and landing speeds by reducing both indicated and true stall speeds. |
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Term
| Describe how different high lift devices affect the values of CL, CLMAX and CLMAX AOA |
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Definition
CL is limited by the AOA at which boundary separation occurs. if airflow separation can be delayed to a higher AOA, the CLMAX and CLMAX AOA will increase. Actual value of CL for an AOA doesn't change before approaching stall speed though.
For Camber change devices, these increase the maximum value of CL and CL for a given AOA but decrease CLMAX AOA. |
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Term
| Describe devices used to control boundary layer separation |
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Definition
Fixed slots allow air to flow through at higher AOAs and only cause a small increase in drag. Slats are leading edge sections used to create automatic slots. Some are mechanically controlled and others use the high static pressure at high AOAs to open.
No change to camber so no change to CL at low AOA. Higher CLMAX is for high AOAs.
BLC can also be achieved with vortex generator, small vanes to turn laminar into turbulent air earlier and adhere better to the wing. |
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Term
| Describe devices used to change the camber of an airfoil |
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Definition
Most common method, increases CL at all AOAs, but decreases CLMAX AOA. Flaps are most common, either trailing or leading edge. Increase lift and increase drag. Allow higher power and steeper glideslope on final
Plain flap - simple hinge.
Split flap - drops down from back. More drag.
Slotted flap - also does BLC on open
Fowler flap - moves down and out, increasing surface area and create slots for BLC. Large twisting moment; need very sturdy construction |
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Term
| Describe methods of stall warning used in the T-6B |
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Definition
| Stick shaker activated at 15.1 AOA, followed by aircraft buffering (stall strip to cause stall right next to cockpit first). AOA sensed via probe. 18 is CLMAX AOA |
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Term
| Describe the stall tendency of the general types of wing planforms |
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Definition
Rectangular - stalls out from center
highly tapered - stiff and strong,
but strong tip stall tendency
swept wings - reduce drag, allow higher supersonic speeds. stall easily and stall tip first strongly
elliptical wing - even stall tendency (shorter warning). Ideal L/D ratio subsonic
moderate taper - similar to elliptical, undesirable. |
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Term
| Describe the various methods of wing tailoring |
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Definition
geometric twist
aerodynamic twist
stall strips
stall fences |
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Term
| Define takeoff and landing airspeed in terms of stall speed |
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Definition
takeoff - 1.2 times stall speed
landing - 1.3 times stall speed |
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Term
| State the various forces acting on an airplane during the takeoff and landing transition |
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Definition
rolling friction
net accelerating force (T - D - Fr) |
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Term
| State the factors that determine the coefficient of rolling friction |
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Definition
| coefficient of friction (surface, condition, type of tire and amount of breaks), Weight and inverse to lift generated |
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Term
| Describe the effects on takeoff and landing performance, given variations in weight, altitude, temperature, humidity, wind and braking |
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Definition
weight higher means takeoff and landing longer.
Altitude - decreases takeoff and landing performance
temperature - hot lowers landing performance
humidity - wet lowers performance
wind - decrease takeoff distance/time; shortens |
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Term
| Describe the effects of outside air temperature (OAT) on airplane performance characteristics |
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Definition
| in general, increasing temperature above standard day conditions raises DA which decreases aircraft performance. can't go as fast, long or as powerful. |
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Term
| Define maximum angle of climb and maximum rate of climb profiles |
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Definition
max angle - greatest climb height over shortest distance traveled
max rate - greatest climb height over shortest time period |
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Term
| Explain the performance characteristics profiles that yield maximum angle of climb and maximum rate of climb for turboprops |
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Definition
max angle - max thrust excess. Occurs at velocity lower than L/DMax and AOA higher.
max rate - found at max power excess. occurs at L/DMax for prop. |
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Term
| Describe the effect of changes in weight, altitude, configuration, and wind on maximum angle of climb and maximum rate of climb profiles |
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Definition
| weight, altitude, configuration dirty will all decrease performance for both. headwind increases angle of climb, does not affect rate. tailwind decreases angle, not rate |
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Term
| Describe the performance characteristics and purpose of the best climb profile for the T-6B |
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Definition
| 140 KIAS. meets or exceeds any obstacle clearance requirements while providing greater safety margin. faster than angle of climb. maximizes both rate and angle; somewhere between the two. allows for an efficient climb that is not close to stalling (like angle usually is) |
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Term
| Define absolute ceiling, service ceiling, cruise ceiling, combat ceiling and maximum operating ceiling |
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Definition
absolute ceiling - max climb rate of zero. power available at full throttle is power required.
service ceiling - climb rate of 100 fpm
cruise ceiling - climb rate of 300 fpm
combat ceiling - climb rate of 500 fpm (more maneuverability)
max operating ceiling - recommended limit for an aircraft (do not exceed) |
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Term
| State maximum operating ceiling of the T-6B |
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Definition
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Term
| State relationship between fuel flow, power available, power required and velocity for a turboprop airplane in straight and level flight |
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Definition
| fuel flow directly related to power available. Max is max power excess point, Minimum fuel flow found at minimum power required. look at PA and PR curves to determine what airspeed to fly. |
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Term
| Define maximum range and maximum endurance profiles |
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Definition
Max range: maximum distance traveled over ground for given amount of fuel.
Max endurance: maximum time in air for given amount of fuel. |
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Term
| Explain performance characteristics profiles that yield maximum endurance and maximum range for turboprops |
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Definition
max endurance - found at minimum power consumption; slower and higher AOA than L/DMax for turboprop. 8.8 units AOA for T-6B
max range - found at L/D Max on power curve. 4.4 units AOA for T-6B |
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Term
| Describe effect of changes in weight, altitude, configuration and wind on maximum endurance and max range performance and airspeed |
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Definition
higher altitude increases max range and max endurance; burns fuel at a slower rate, increases airspeed
higher weight decreases endurance and range; needs to burn more fuel to generate lift required and fly faster airspeed
flaps and gear decrease both endurance and range - more drag generated, don't change airspeed
wind - headwind decreases max range but not endurance. increases airspeed for range in order to counter headwind. doesn't change for endurance. tailwind does opposite. |
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Term
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Definition
| ratio of an airplane's speed through an air mass to the speed of sound through that same air mass |
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Term
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Definition
| speed above which airplane is not designed to fly; can sustain damage to structures above this |
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Term
| State effects of altitude on Mach number and critical Mach number |
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Definition
| increases altitude increases mach number; TAS increases and LSOS decreases. critical mach number stays the same; but you are closer to reaching it as you climb |
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Term
| Define maximum glide range and maximum glide endurance profiles |
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Definition
max glide range - longest distance with no thrust available (engine idle) - Vbest for T-6B is 125 KIAS
max glide endurance - longest time in air with no power available |
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Term
| Explain performance characteristics profiles that yield maximum glide range and maximum glide endurance |
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Definition
max glide range - found at minimum thrust deficit - found at L/D Max for turboprop.
max glide endurance - found at minimum power deficit - left of L/D Max (higher AOA and lower airspeed) |
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Term
| Describe effect of changes in weight, altitude, configuration, wind and prop feathering on max glide range and max glide endurance performance and airspeed |
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Definition
weight - no change to range but does increase airspeed. decreases endurance, increases speed.
altitude - increases both range and endurance (more distance/time to fall)
configuration - decreases both endurance and range- parasite/induced drag increases
wind - headwind reduces range, not endurance. tailwind does opposite; increasing range, not changing endurance
prop feathering - improper feathering (inward) can reduce both range and endurance |
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Term
| Describe locations of regions of normal and reverse command on the turboprop power curve |
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Definition
| Reverse command is airspeeds less than the minimum power required point (left of L/DMAX) and normal command is any airspeed setting where power required increases as velocity increases (right of PRmin) |
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Term
| Explain relationship between power required and airspeed in regions of normal and reverse command |
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Definition
reverse command - as airspeed decreases, power required increases and angle of attack increases
normal command - as airspeed increases, power required increases and angle of attack decreases |
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Term
| Define nose wheel liftoff/touchdown speed |
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Definition
nose wheel liftoff speed - minimum safe speed to allow nose wheel to leave runway during takeoff
nose wheel touchdown speed - minimum safe speed at which nose wheel must return to the runway following a landing |
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Term
| State pilot speed and attitude inputs necessary to control airplane during a crosswind landing |
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Definition
| place ailerons into the wind, rudder in same direction to maintain coordinated flight. maintain required airspeed |
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Term
| State crosswind limits for the T-6B |
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Definition
| 25 knots crosswind component maximum |
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Term
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Definition
| tires skimming atop a thin layer of water on the runway |
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|
Term
| State factors that affect speed at which an airplane will hydroplane |
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Definition
| tire pressure is the only direct factor. independent of weight. |
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Term
| Describe effects of propeller slipstream swirl, P-factor, torque and gyroscopic precession as they apply to the T-6B |
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Definition
propeller slipstream swirl - air from propellers impart corkscrew motion, high power/low airspeed pulls tail to right, nose left
p-factor - most prevalent at high or low (negative) AOAs. Causes more thrust to be made by one side or other of propeller.
torque - turning motion clockwise tends to roll airplane CCW
gyroscopic precession - resultant force to gyroscope (propeller spinning) is 90 degrees ahead. nose up causes force on left propeller, yawing right. nose down causes force on right propeller, yaw left. |
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Term
| Describe what the pilot must do to compensate for propeller slipstream swirl, P-factor, torque and gyroscopic precession as they apply to the T-6B |
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Definition
slipstream swirl - horizontal lifting force that adds nose-left yaw tendency. add right rudder and control stick to compensate
p-factor - at high angles of attack, right down-going blade creates more thrust and tends to yaw nose-left. add right rudder. at negative angles of attack, left up-going propeller will yaw nose right and left rudder is required.
torque - slight aileron right
gyro precession - when nose down, right rudder. nose up, left rudder |
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Term
| Describe effect of lift on turn performance |
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Definition
| more lift is required to turn at a steeper angle of bank, and hence a smaller turn radius and faster turn rate |
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Term
| Describe effect of weight on turn performance |
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Definition
| turn rate and radius are independent of weight; heavier plane will just require more lift |
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Term
| Describe effect of thrust on turn performance |
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Definition
| thrust limit can limit turn performance; higher g maneuvers can produce more induced drag and thrust must be able to counter this |
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Term
| Describe effect of drag on turn performance |
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Definition
| drag is proportional to lift squared; drag increases quickly for more lift; can limit how tight turn radius is |
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Term
| Define turn radius and turn rate |
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Definition
turn radius - measure of the radius of the circle that the flight path creates
turn rate - rate of heading change, degrees per second |
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Term
| Describe the effects of changes in bank angle on turn performance |
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Definition
| more bank (higher bank angle) decreases turn radius and increases turn rate up until thrust limit or 90 degrees. Reverse is true. |
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Term
| Describe the effects of changes in airspeed on turn performance |
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Definition
| faster airspeed will increase turn radius and decrease turn rate |
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Term
| Describe the effects of aileron and rudder forces during turns |
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Definition
| aileron creates roll force ( more lift on up-going wing and negative lift on down-going wing). rudder creates yawing motion to prevent slip or skid (coordinated turn) |
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Term
| Explain the aerodynamic principle that requires two Gs of back stick pressure to maintain level, constant airspeed flight at 60 degrees angle of bank |
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Definition
| lift is perpendicular to relative wind, so when lift turns toward horizontal, the total lift must increase to maintain level, constant-airspeed flight. |
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Term
| Describe the relationship between load factor and angle of bank for level, constant-airspeed-flight |
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Definition
| as angle of bank increases, load factor increases exponentially. angle of bank is limited by the aircraft's limit load factor (+7G for T-6B, or 83 degrees) |
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Term
| Define load, load factor, limit load factor, and ultimate load factor |
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Definition
load - stress-producing force imposed onto an airplane or component
load factor - acceleration due to lift expressed as a multiple of the earth's acceleration (measured by accelerometer)
limit load factor - greatest load factor an airplane can sustain without any risk of permanent deformation. Max load factor anticipated in normal daily operations
ultimate load factor - max load factor airplane can withstand without structural failure |
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Term
| Define static strength, static failure, fatigue strength, fatigue failure, service life, creep and overstress/over-G |
|
Definition
static strength - measure of material's resistance to single application of steadily increasing load or force
static failure - breaking or serious permanent deformation of a material due to a single application of a steadily increasing load or force
fatigue strength - measure of a material's ability to withstand a cyclic application of load or force
fatigue failure - breaking or serious permanent deformation of a material due to a cyclic application of load or force
service life - the number of applications of load or force that a component can withstand before it has the probability of failing. fatigue strength plays a major role in service life.
creep - metal's tendency to stretch or elongate when subjected to high stress and temperature
overstress - condition of possible permanent deformation or damage that results from exceeding the limit load factor. weakens the airplane's basic structure |
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Term
| Define maneuvering speed, cornering velocity, redline airspeed, accelerated stall lines and the safe flight envelope |
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Definition
maneuvering speed - IAS at the maneuver point (where accelerated stall line and limit load factor line intersect)
cornering velocity - same as maneuvering speed: lowest airspeed at which limit load factor can be reached. below, stall before reaching limit load. T-6B = 227 KIAS at max weight
redline airspeed - highest airspeed an airplane is ever allowed to fly. above causes structural damage
accelerated stall lines - lines of maximum lift; max load factor an airplane can produce based on airspeed. Determined by CLMAX AOA. Can pull more G's as airspeed increases
Safe flight envelope - portion of V-n diagram bounded by the accelerated stall lines, limit load factors and the redline airspeed |
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Term
| Describe the boundaries of the safe flight envelope, including accelerated stall lines, limit load factor, ultimate load factor, maneuver point and redline airspeed |
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Definition
| on left top/bottom: accelerated stall lines for positive and negative G's, limit load factor at negative and positive G limits and redline airspeed. maneuver point between stall line and positive limit load factor, redline airspeed bounds on right |
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Term
| Define asymmetric loading and state the associated limitations for the T-6B |
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Definition
| asymmetric loading - uneven production of lift on the wings of an airplane. may be caused by rolling pullout, trapped fuel or hung ordnance. for T-6B , max load factor during asymmetric loading is +4.7 to -1.0 G's |
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|
Term
| Define static stability and dynamic stability |
|
Definition
Static stability - initial tendency of an object to move toward or away from its original equilibrium position
dynamic stability - position with respect to time; motion of object after a disturbance |
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Term
| Describe the characteristics exhibited by aircraft with positive, neutral and negative static stabilities when disturbed from equilibrium |
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Definition
| AC with positive static stability will tend to move back toward equilibrium when disturbed. Neutral will stay in position it moves to. Negative will continue to move/rotate in that direction when disturbed |
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Term
| Describe the characteristics of damped, undamped and divergent oscillations, and the combination of static and dynamic stabilities that result in each |
|
Definition
damped - returns toward original position; overshoots and oscillates smaller each time until reaching static position. positive dynamic stability and positive static stability.
undamped - oscillates at same magnitude toward original position with no dampening - positive static and neutral dynamic
divergent - oscillates at an increasingly large magnitude, never to fully return to center; positive static/negative dynamic |
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|
Term
| Explain the relationship between stability and maneuverability |
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Definition
| Maneuverability and stability are opposites. Stable plane resists maneuvers. Maneuverable plane is less stable. |
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Term
| State the methods for increasing an airplane's maneuverability |
|
Definition
Two methods:
moving quickly from its trimmed equilibrium attitude - give it weak stability (harder to fly in equilibrium flight)
Increase control surface size - generate large moments by producing greater aerodynamic forces. Transport plane must be stable for long range flights/ease of landing. fighter must have great maneuverability |
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|
Term
| State effects of airplane components on an airplane's longitudinal static stability |
|
Definition
Positive longitudinal static - CG in front of aerodynamic center
negative longitudinal static - CG behind aero center
straight wings generally have AC in front of CG, so negative
fuselage - negative
horizontal stabilizer - positive
neutral point - CG forward of this is overly stable (nose down), behind is unstable (think of as AC for entire plane) |
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|
Term
| Explain the criticality of weight and balance |
|
Definition
| When aircraft is not within CG limits, it can become out of control, and control surfaces will not create enough moment to effectively control the airplane. Can crash. |
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|
Term
| State the effects of airplane components on an airplane's directional static stability |
|
Definition
reaction to sideslip motion defines the directional static stability
straight wings - positive effect: parasite drag pulls back on forward wing with airflow velocity increase
swept wings - even more so than straight wings: more parasite and induced drag
fuselage - negative (wind pushes it more)
vertical stabilizer - greatest positive contributor |
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|
Term
| State the effects of airplane components on an airplane's lateral static stability |
|
Definition
if airplane rolls, it brings itself level
dihedral - greatest positive contributors: up-going wing has decrease in lift and down-going wing has increase in lift
high-mounted wing blocks airflow from sideslip, increases lift on down wing and rolls back. low mounted wings are negative contributors
wing sweep - positive contributor down wing lifts more |
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|
Term
| State the static stability requirements for, and effects of, directional divergence |
|
Definition
| side slip increases itself - negative directional stability and negative static stability |
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|
Term
| State static stability requirements for, and effects of, spiral divergence |
|
Definition
| strong directional stability and weak lateral stability - tight descending spiral (death spiral |
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|
Term
| State static stability requirements for, and effects of, dutch roll |
|
Definition
| strong lateral stability, weak directional stability. overall maintain direction but nose yaw/pitch in slight sideways figure eight form |
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|
Term
|
Definition
| the tendency of an airplane to roll in the same direction as it is yawing |
|
|
Term
|
Definition
| the tendency of an airplane to yaw in the opposite direction as it is rolling |
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|
Term
| Explain how an airplane develops phugoid oscillations |
|
Definition
| long periodic oscillations of 20-100 seconds - updraft causes increase in altitude, decrease in speed. lose airspeed, nose down, nose will pitch up when airspeed regained |
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|
Term
| Explain how an airplane develops pilot induced oscillations |
|
Definition
| over-correction of pitch attitude and angle of attack for oscillations. adding too much control input for something that would have corrected itself anyway so the inputs compound |
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|
Term
|
Definition
| more thrust on one side than the other, such as if one of two engines fail. the excess thrust will create a yawing moment. need to fly fast enough (minimum) to overcome and have effectiveness of vertical stabilizer (rudder) |
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