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CHAPTER 1
1. Lift and Drag forces on an airplane are: scalars and are resultants of the Aerodynamic Force. vectors and are resultants of the Aerodynamic Force. scalars and are components of the Aerodynamic Force. vectors and are components of the Aerodynamic Force. 2. Lift on an airplane acts: parallel to the flight path. opposite to the weight. perpendicular to the flight path. perpendicular to the horizontal. 3. Which of the following are all vector quantities? Velocity, time, displacement. Displacement, acceleration, force. Force, displacement, volume. Velocity, mass, force. 4. An airplane is flying to the south at 200 knots and encounters a 20 knot wind from the north. The groundspeed of the airplane will be: 180 knots with no drift. 200 knots with a drift to the east. 220 knots with no drift. 200 knots with a drift to the west. 5. An airplane is making a constant airspeed, level turn. Its velocity: is increasing.
is decreasing. remains the same. is changing.
**6. Which dimension of the drawing is the moment arm?
- An airplane is making its takeoff run. It is:** In equilibrium. Accelerating according to Newton's third law. Not in equilibrium. About to crash because F = ma. 8. The term "work" means: A body moves as a result of balanced forces. A frictionless body moves at constant velocity. A force is exerted upon a body. A body moves as a result of an unbalanced force. 9. How much horsepower does a 10,000 pound thrust jet engine produce? 10,000 HP. 30.77 HP. Zero HP. Can't calculate until velocity is known. 10. How much greater will the stopping force be with the brakes applied for 10% slip as with the brakes locked (100% slip)? (see Figure 1.8) Same. 7/5. Twice. Need to know the weight.
if the area of a tube decreases, the static pressure of the air increases. if the velocity of an airstream within a tube increases, the static pressure of the air decreases, but the sum of the static pressure and the velocity remains constant. none of the above.
6. Dynamic pressure of an airstream is: directly proportional to the square of the velocity. directly proportional to the air density. neither a. nor b. above. both a. and b. above. 7. In this book, we use the formula for dynamic pressure, q = aV2/295, rather than the more conventional formula, q = 1/2pV2 , because: V in our formula is measured in knots. density ratio is easier to handle (mathematically) than the actual density (slugs per cubic foot). both a. and b. above. neither a. nor b. above. 8. The corrections that must be made to Indicated Airspeed (IAS) to obtain Calibrated Airspeed (CAS) are: position error and compressibility error. instrument error and position error. instrument error and density error. position error and density error. 9. The correction that must be made to CAS to obtain Equivalent Airspeed (EAS) is called compressibility error, which:
is always a negative value. can be ignored at high altitude. can be ignored at high airspeed. can be either a positive or a negative value.
10. The correction from EAS to True Airspeed (TAS) is dependent upon: temperature ratio alone. density ratio alone. pressure ratio alone. none of the above. **CHAPTER 3
- Number 3 on the above sketch shows:** the chord line. the maximum camber. the thickness. the mean camber line. 2. Number 4 on the above sketch shows: the chord line. the thickness. the maximum camber. the mean camber line. 3. Number 5 on the above sketch shows: the maximum camber. the mean camber line. the upper surface curvature.
both a. and c. above.
9. Which of these statements is false? For a cambered airfoil: the AC is where all changes in lift effectively take place. there is no pitching moment at the AC. the AC is located near 25% C subsonically. the pitching moment at the AC is constant with change of AOA (at constant airspeed). 10. For a symmetrical airfoil, the center of pressure: moves forward as AOA increases. stays at the same place as AOA increases. has no pitching moment about both b. and c. above. **CHAPTER 4
- As thickness of an airfoil is increased, the stall AOA:** is greater. is less c. remains the same. 2. As camber of an airfoil is increased, its C L at any AOA: is less. remains the same. c. is greater. 3. Air in the boundary layer: has zero velocity at the wing surface. is turbulent near the leading edge.
is more apt to stall if it is turbulent. none of the above.
4. Air in the boundary layer: changes from laminar to turbulent at low Reynolds numbers. separates from the wing when its velocity is maximum. reverses flow direction when stall occurs. none of the above. 5. Two things an airfoil designer can change to increase Cummo are: thickness and wing area. chord length and aspect ratio. camber and wing span. **thickness and camber.
- High values of Reynolds number will more likely:** occur near the leading edge of an airfoil. indicate laminar flow. occur at lower airspeeds. shows turbulent airflow. 7. Adverse pressure gradient on an airfoil is found: from the point of maximum thickness to the trailing edge. near the stagnation point at the leading edge. from the point of minimum pressure to the trailing edge. both a. and c. above. 8. At low velocity stall, the air flow: stops. reverses direction.
3. Laminar flow airfoils have less drag than conventional airfoils because: the adverse pressure gradient starts farther back on the airfoil. the airfoil is thinner. more of the airflow is laminar. both a. and c. above. 4. Lift/Drag ratio is: a measure of the aircraft's efficiency. a maximum when the drag is a minimum. numerically equal to the glide ratio. all of the above. 5. An airplane flying at C L mAx) will have: more parasite drag than induced drag. more induced drag than parasite drag. equal amounts of parasite and induced drag. not enough information given to determine. 6. Induced drag is : more important to low aspect ratio airplanes than to high aspect ratio airplanes. reduced when the airplane enters "ground effect". reduced if the airplane has winglets. all of the above. 7. Induced drag results from the lift vector being tilted to the rear. This is caused by: the tip vortices cause downwash behind the wing. the relative wind behind the wing is pushed downwards. the local relative wind at the AC is depressed. all of the above.
- An airplane with a heavy load _____when lightly loaded. can glide farther than can not glide as far as can glide the same distance as 9. If an airplane has a symmetrical wing which has an angle of incidence of 0° during takeoff, all the drag is: profile drag. parasite drag. wave drag. induced drag. 10. A low tailed airplane with static ports beneath the wing leaves "ground effect" after takeoff. It will have: increased drag, nose up pitch, lowered IAS. increased drag, nose up pitch, higher IAS. decreased drag, nose down pitch, lowered IAS. decreased drag, nose up pitch, higher IAS. **CHAPTER 6
- The formula TA = Q(V2-V1) shows:** you can get more thrust from a jet engine by using water injection. you can get more thrust from a jet engine by decreasing the exhaust pipe area. neither of the above. both a. and b. above. 2. Q in TA = Q(V2-V1) is the mass flow (slugs per sec.).
A tailwind is encountered. To get best range now the pilot must: speed up by an amount less than the wind speed. slow down by an amount equal to the wind speed. slow down by an amount more than the wind speed. slow down by an amount less than the wind speed.
- To obtain maximum range a jet airplane must be flown at: a speed less than that for (L/D)mAx. a speed equal to that for (L/D). c. a speed greater than that for (L/D)mAx. 9. Maximum rate of climb for a jet airplane occurs at: a speed less than that for (1,M)mAx. a speed equal to that for (L/D)mAx. c. a speed greater than that for (L/D)mAx. 10. Maximum climb angle for a jet aircraft occurs at: a speed less than that for (L/D)mAx. a speed equal to that for (L/D)mAx. c. a speed greater than that for (L/D)mAx. **CHAPTER 7
- If the weight of a jet airplane is increased the:** parasite drag increases more than induced drag. induced drag decreases more than parasite drag. both parasite and induced drag increase by the same amount. induced drag increases more than parasite drag.
2. If the weight of a jet airplane is reduced as fuel is burned, the T R curve: moves down and to the right. moves up and to the right. moves down and to the left. moves up and to the left. 3. If a jet airplane is in the gear down configuration, the increase in: parasite drag is more than that of the induced drag. induced drag is more than that of the parasite drag. c. both types of drag are the same. 4. If it is impossible to raise the landing gear of a jet airplane, to obtain best range, the airspeed must be from that for the clean configuration. increased. decreased. c. not changed. 5. From Figure 7.4 find the glide ratio (L/D)mA,x for the airplane in the full flaps and gear down configuration.
6. The minimum drag for a jet airplane does not vary with altitude. True. False. 7. Figure 7.5 shows an increase in specific range with altitude because: TR decreases while fuel flow decreases.
2. Power is: (force x velocity)/time. work/time. (force x distance)/time. both b. and c. above. 3. Power required to overcome induced drag varies: inversely with V2. inversely with V3. inversely with V. directly with V. 4. Power required to overcome parasite drag varies: directly with V2. directly with V3. directly with V. inversely with V2. 5. Maximum rate of climb for a propeller airplane occurs: at (L/D)mAx. at PRA. at Cvmmo• at (PA-PR)mAx. 6. The lowest point on the PR curve is (L/D)mAx. True. False. 7. Propeller aircraft are more efficient than jet aircraft because: they don't go so fast.
they process more air and don't accelerate it as much. they use gasoline instead of JP fuel. V1 is less, so propulsive efficiency is greater.
8. Turboprop aircraft are classified as power producers because: nearly all of the engine output goes to the propeller. the engine is a turbine engine. the fuel flow is proportional to the power produced. both a. and c. above. 9. Helicopters have another power requirement over fixed wing propeller airplanes. It is called: induced power required. parasite power required. profile power required. total power required. 10. Propeller aircraft get the highest angle of climb at (L/D). True. False. CHAPTER 9 lightly loaded propeller airplane will be able to glide than when it is heavily loaded. farther. less far. c. the same distance. 2. To obtain maximum glide distance, a heavily loaded airplane must be flown at a higher
the turbine engine wants to fly at high altitudes. the propeller has higher efficiency at lower altitudes. c. this is a compromise between a. and b. above.
8. The Power required curves for an increase in altitude show that the: PR remains the same as altitude increases. PR increases by the same amount as the velocity. c. PR increases but the velocity does not.
- A propeller aircraft in the dirty condition shows that the P R moves up and to the left over the clean configuration. This is because: the increase in the induced PR is more at low speed. the increase is mostly due to parasite P R. c. they both increase by the same amount. 10. The increase in the PR curves for a weight increase is greater at low speeds than at high speeds because the increase in: induced PR is greatest. parasite PR is greatest. c. profile PR is greatest. **CHAPTER 11
- The main difference between the C L - a curves for straight winged aircraft are:** The swept wing aircraft has a lower value of CL(,,,,00. The straight wing aircraft does not fly at as high an AOA for CL(mm. The swept wing aircraft does not have an abrupt loss of lift at CL.
All of the above.
2. Low speed stall will start at the wing's trailing edge where C1/CL is a minimum. where C1/CL is a maximum. at the root for a swept wing. at the wing tip for a straight rectangular wing. 3. The "Region of Reversed Command", for a jet aircraft is also correctly known as: the backside of the thrust required curve. the backside of the power curve. the backside of the drag curve. both a. and c. above. 4. An aircraft should never be flown in the "Region of Reversed Command." True. False. 5. Pulling back on the control stick (or yoke) will cause the airplane to climb if the plane is flying at: low speed. high speed. c. any speed. 6. A better way to climb, which will work at any speed, is to control the airspeed with the stick and add throttle to climb. True. False. 7. An airplane is making a final approach for a landing and encounters a horizontal wind shear. Which of the below types of bursts is the most dangerous?
