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Chapter 14 – Airplane Performance: Know Before You Go

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Chapter 14 – Airplane Performance: Know Before You Go 14-1 Chapter 14 – Airplane Performance: Know Before You Go Air Density Density Altitude 1. [14[14[14-[14 ---1/3/3]1/3/3] 6. [14[14[14-[14 ---3/All]3/All] Anything reducing the amount of air the engine swal- Density altitude is lows diminishes its _____ output. A. the height above the standard datum plane. A. hydrocarbon B. pressure altitude corrected for nonstandard B. fuel temperature. C. power C. the altitude read directly from the altimeter. Height 2. [14[14[14-[14 ---2/1/3]2/1/3] 7. [[14141414----3/1/5]3/1/5] The higher you go the _____ dense the air is. The term _____ describes how dense the air feels to A. less the airplane, regardless of the airplane’s present B. more or less height above sea level. C. more A. density altitude Heat B. pressure altitude 3. 141414-14 ---2/1/4]2/1/4] C. true altitude Heated air is much ­­­­_____ dense than colder air. A. more or less 8. [[14141414----3/1/5]3/1/5] B. more Which factor would tend to increase the density alti- C. less tude at a given airport? Humidity A. An increase in barometric pressure. 4. [14[14[14-[14 ---2/1/5]2/1/5] B. An increase in ambient temperature. What effect, if any, does high humidity have on aircraft C. A decrease in relative humidity. performance? A. It increases performance. 9. [14[14----3/2/2]3/2/2] B. It decreases performance. Density altitude, and its effect on landing perform- C. It has no effect on performance. ance, is defined by A) pressure altitude and ambient temperature. 5. [14[14[14-[14 ---3/1/1]3/1/1] B) headwind and landing weight. Which combination of atmospheric conditions will C) humidity and braking friction forces. reduce aircraft takeoff and climb performance? A. Low temperature, low relative humidity, and low 101010.10 . [14[14[14-[14 ---3/2/3]3/2/3] density altitude. What are the standard temperature and pressure val- B. High temperature, low relative humidity, and low ues for sea level? density altitude. A. 15 degrees C and 29.92" Hg. C. High temperature, high relative humidity, and high B. 59 degrees C and 1013.2 millibars. density altitude. C. 59 degrees F and 29.92 millibars. 14-2 Rod Machado’s Sport Pilot Workbook 111111.. [14[14[14-[14 ---4/1/2]4/1/2] 11171777.. [14[14[14-[14 ---7/1/6]7/1/6] What effect does high density altitude, as compared Which would provide the greatest gain in altitude in to low density altitude, have on propeller efficiency the shortest distance during climb after takeoff? and why? A. Vy A. Efficiency is increased due to less friction on the B. Va propeller blades. C. Vx Vx and Vy Change With Altitude B. Efficiency is reduced because the propeller exerts less force at high density altitudes than at low 11181888.. [. [14[ 141414----8/1/8]8/1/8] density altitudes. The best rate of climb indicated airspeed _____ with C. Efficiency is reduced due to the increased force of an increase in altitude, while the best angle of climb the propeller in the thinner air. indicated airspeed _____ with an increase in altitude. A. decreases, increases 11121222.. [14[14[14-[14 ---4/1/2]4/1/2] B. increases, decreases What effect does high density altitude have on aircraft C. increases, remains constant performance? A. It increases engine performance. Cruise Climb Speed B. It reduces climb performance. C. It increases takeoff performance. 11191999.. [. [14[ 141414----8/1/9]8/1/9] Most of the time it’s preferable to climb at some 11131333.. [. [14[ 141414----4/1/2]4/1/2] speed slightly above _____. If the outside air temperature (OAT) at a given altitude A. Vx is warmer than standard, the density altitude is B. Vy A. equal to pressure altitude. C. Va B. lower than pressure altitude. C. higher than pressure altitude. 202020.20 . [14[14[14-[14 ---8/Figure8/Figure 9] Fill in the blanks: Service Ceiling The graph below belongs to a particular model single- engine airplane. Estimate this airplane’s best angle 11141444.. [14[14[14-[14 ---5/1/1]5/1/1] and best rate of climb speeds. An airplane’s service ceiling is the height at which the Vx is _______________. climb rate drops to less than _____ feet per minute. Vy is _______________. A. 25 B. 50 C. 100 11151555.. [. [14[ 141414----5/1/1]5/1/1] If the density altitude is 13,000 feet and the airplane’s service ceiling is 13,000 feet, the airplane will most likely climb at a rate of _____ at this altitude. A. more than 100 FPM B. less than 100 FPM C. 500 fpm Best Rate and Best Angle of Climb 11161666.. [14[14[14-[14 ---7/1/5]7/1/5] After takeoff, which airspeed would the pilot use to gain the most altitude in a given period of time? A. Vy B. Vx C. Va 14-3 Chapter 14 – Airplane Performance: Know Before You Go Takeoff Distance Chart 22212111.. [. [14[ 141414----10/1/1/Entire10/1/1/Entire section] 22232333.. [14[14[14-[14 ---10/1/1/Entire10/1/1/Entire section] Referring to the performance chart below, determine Referring to the performance chart below, determine the total distance required for takeoff to clear a 50 foot the total distance required for takeoff to clear a 50 foot obstacle. obstacle. OAT: Standard temperature OAT: Standard temperature Pressure altitude: 5,000 ft Pressure altitude: Sea level Takeoff weight: 2,800 lb Takeoff weight: 2,700 lb Headwind component: calm Tailwind component: calm A. 1,150 feet. A. 1,000 feet. B. 1,800 feet. B. 1,300 feet. C. 2,000 feet. C. 1,700 feet. 222222.. [14[14[14-[14 ---10/1/1/Entire10/1/1/Entire section] 22242444.. [14[14[14-[14 ---10/1/1/Entire10/1/1/Entire section] Referring to the performance chart below, determine Referring to the performance chart below, determine the approximate ground roll distance required for the approximate ground roll distance required for takeoff. takeoff. OAT: 90 degrees F OAT: 80 degrees F Pressure altitude: 2,000 ft Pressure altitude: 2,500 ft Takeoff weight: 2,500 lb Takeoff weight: 2,250 lb Headwind component: 20 kts Headwind component: 20 kts A. 700 feet. A. 900 feet. B. 850 feet. B. 500 feet. C. 1,000 feet. C. 700 feet. 14-4 Rod Machado’s Sport Pilot Workbook 22252555.. [14[14[14-[14 ---12/2/2/12/2/2/12/2/2/EntireEntire section] 22272777.. [14[14[14-[14 ---12/2/2/Entire12/2/2/Entire section] Referring to the performance chart above, determine Referring to the performance chart above, determine the total distance required for takeoff to clear a 50 foot the approximate ground roll distance required for obstacle. takeoff. OAT: 20 degrees C OAT: 10 degrees C Pressure altitude: 4000 ft Pressure altitude : 4,500 ft Takeoff weight: 1,670 lb Takeoff weight: 1,670 lb Headwind component: 9 kts Headwind component: 9 kts A. 2,288 feet. A. 1,073 feet. B. 2080 feet. B. 965 feet. C. 1,872 feet. C. 1,180 feet. 22262666.. [. [14[ 141414----12/2/2/Entire12/2/2/Entire section] 22282888.. [. [14[ 141414----12/2/2/Entire12/2/2/Entire section] Referring to the performance chart above, determine Referring to the performance chart above, determine the total distance required for takeoff to clear a 50 foot the total distance required for takeoff to clear a 50 foot obstacle. obstacle. OAT: 10 degrees C OAT: 20 degrees C Pressure altitude: 2,000 ft Pressure altitude: 5,500 ft Takeoff weight: 1,670 lb Takeoff weight: 1,670 lb Headwind component: 0 kts Tailwind component: 4 kts Runway: dry, grass A. 2,465 feet. A. 966 feet. B. 1,972 feet. B. 1,439 feet. C. 2,958 feet. C. 1,691 feet. 14-5 Chapter 14 – Airplane Performance: Know Before You Go Landing Distance 33313111.. [. [14[ 141414----14/1/1/Entire14/1/1/Entire section] Referring to the performance chart above, determine 22292999.. [. [14[ 141414----14/1/1/Entire14/1/1/Entire section] the total distance required to land over a 50 foot ob- Referring to the performance chart above, determine stacle. the total distance required to land over a 50 foot ob- stacle. OAT: 90 degrees F Pressure altitude: 4,000 ft OAT: standard Weight 2,800 lb Pressure altitude: 10,000 ft Headwind component: 10 kts Weight: 2,400 lb Obstacle: 50 ft Wind component: calm A. 1,525 feet. Obstacle: 50 ft B. 1,775 feet. A. 750 feet. C. 1,950 feet. B. 1,925 feet. C. 1,450 feet. 33323222.. [. [14[ 141414----14/1/1/Entire14/1/1/Entire section] Referring to the performance chart above, determine 303030.30 . [. [14[ 141414----14/1/1/Entire14/1/1/Entire section] the total distance required to land over a 50 foot ob- Referring to the performance chart above, determine stacle. the approximate ground roll distance after landing. OAT: 90 degrees F OAT: 80 degrees F Pressure altitude: 3,000 ft Pressure altitude: 5,000 ft Weight 2,900 lb Weight: 2,600 lb Headwind component: 10 kts Tailwind component: 10 kts Obstacle: 50 ft A. 1,750 feet. A. 1,450 feet. B. 1,200 feet. B. 1,550 feet. C. 1,050 feet. C. 1,725 feet. 14-6 Rod Machado’s Sport Pilot Workbook A Different Landing Distance Chart 33363666.
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