Aviation ClubAirplane PerformanceJeppesen Chapter 8

Chapter 8

Airplane Performance

Section A Predicting Performance

1. Performance Charts- Reference in Pilot Operating Handbook (POH)

2. Factors affecting Performance

a. Weight

i. Weight, Performance

b. Wind

i. Headwind, crosswind, tailwind components

c. Atmospheric Conditions

i. Air Density, Performance

ii. Altitude, Temperature, Pressure, and Humidity affect Air Density

iii. Density Altitude Pressure altitude corrected for nonstandard temperature

1. e.g. on a hot day, density altitude may be higher than field elevation

2. as density altitude increases, engine power output, propeller efficiency, aerodynamic lift, and takeoff/landing performance all decrease

3. at standard temperature, density altitude = pressure altitude

3. Takeoff/Landing Performance

a. Takeoff Performance Charts

i. Show total distance required to clear a 50-foot obstacle

b. Landing Distance Graph

i. Gives total distance required to land and approximate ground roll distance

4. Climb Performance

a. (Vx) Best angle of climb

i. Greatest gain in altitude in shortest distance

ii. obstacle clearance immediately after take-off

iii. visibility limited

b. (Vy) Best rate of climb

i. Greatest gain in altitude in a given time

c. Absolute Ceiling airplane cant go any higher

i. As altitude increases, the Vx and Vy decrease. The point where Vx and Vy intersect is the absolute ceiling of the airplane.

d. Service Ceiling single-engine airplane is able to maintain a maximum climb of only 100 feet per minute (practical ceiling)

5. Cruise Performance

a. Cruising speed cover maximum distance in shortest period of time, but consider fuel/oil/weather etc.

b. Maximum level flight speed force of total drag equals force of full thrust (acceleration = 0, speed maximized)

c. Maximum range speed- travel the greatest distance for a given amount of fuel

d. Maximum endurance speed remain aloft for the longest possible time

e. Cruise Performance Tables

i. Calculate manifold pressure, fuel flow, fuel consumption, and true airspeed

Section B Weight and Balance

1. Center of Gravity (CG) imaginary point where aircraft would balance is suspended

a. CG limits = forward and aft center of gravity locations within which the aircraft must be operated at a given weight

b. Reference Datum- an imaginary vertical plane from which all horizontal distances are measured for balance purposes (see POH)

2. Weights

a. Basic Empty Weight includes weight of airplane, operational equipment, unusable fuel, and full operating fluids including full engine oil

b. Ramp Weight airplane loaded for flight prior to engine start

c. Takeoff Weight Ramp weight fuel burned during engine start, runup, and taxi

d. Landing Weight takeoff weight fuel burned enroute

3. Loads

a. Useful Load Ramp Weight Basic Empty Weight (includes weight of flight crew and usable fuel, as well as any passengers, baggage and cargo)

b. Payload- weight of only the passengers, baggage and cargo

4. Calculation Tips

a. Gasoline is 6 pounds/gallon

b. Oil weights 7 pounds/gallon (1 pounds/quart)

5. Physics

a. Arm distance from the datum (inches)

b. Moment a measure of the tendency of the weight to cause rotation at the fulcrum (pound-inches)

c. CG Formula:

d. Weight-Shift Formula:

Section C Flight Computers

1. Computer Side

a. Pointer = Speed Index

b. A Scale non-rotating outer scale

c. B scale outermost rotating scale

d. Logarithmic!

e. Time, speed, distance, fuel consumption, density altitude, true airspeed, conversion problems

2. Wind Side

a. Wind Vector headwind/tailwind component and crosswind component

b. Course indicated path over the ground

c. Heading direction that nose of airplane points

d. Wind Correction Angle (WCA) compensate for drift and remain on course

FAA Flight Exam Questions

http://www.webexams.com/exam/browse?exam=150 [Check: H303, H315, H316, H317, I22]

http://www.Exams4Pilots.org [Check: H316, H317, H940, H941, H945, H946]

1. Refer to figure 36. What fuel flow should a pilot expect at 11,000 feet on a standard day with 65 percent maximum continuous power?

A. 11.8 gallons per hour.

B. 11.2 gallons per hour]

C. 10.6 gallons per hour.

2. What type fuel can be substituted for an aircraft if the recommended octane is not available?

A. Unleaded automotive gas of the same octane rating.

B. The next higher octane aviation gas

C. The next lower octane aviation gas.

3. Refer to figure 38. Determine the total distance required to land.

OAT

32 F

Pressure altitude

8,000 ft

Weight

2,600 lb

Headwind component

20 kts

Obstacle

50 ft

A. 1400 feet

B. 1750 feet

C. 850 feet

4. Where may an aircraft's operating limitations be found?

A. In the current, FAA-approved flight manual, approved manual material, markings, and placards, or any combination thereof.

B. On the Airworthiness Certificate.

C. In the aircraft airframe and engine logbooks.

5. The angle of attack at which an airplane wing stalls will

A. increase if the CG is moved forward

B. remain the same regardless of gross weight

C. change with an increase in gross weight

6. Refer to figures 33 and 34. Determine if the airplane weight and balance is within limits. Front seat occupants..................415 lb Rear seat occupants...................110 lb Fuel, main tanks..........................44 gal Fuel, aux. tanks..........................19 gal Baggage....................................32 lb

A. 19 pounds overweight, CG out of limits forward

B. Weight within limits, CG out of limits

C. 19 pounds overweight, CG within limits

7. Refer to figure 41. Determine the total distance required for takeoff to clear a 50-foot obstacle.

OAT

Std

Pressure altitude

4,000 ft

Takeoff weight

2,800 lb

Headwind component

Calm

A. 1750 feet

B. 2000 feet

C. 1500 feet

8. Which combination of atmospheric conditions will reduce aircraft takeoff and climb performance?

A. Low temperature, low relative humidity, and low density altitude.

B. High temperature, low relative humidity, and low density altitude

C. High temperature, high relative humidity, and high density altitude.

9. What effect, if any, does high humidity have on aircraft performance?

A. increases engine performance

B. reduces climb performance

C. increases takeoff performance

10. Refer to Figure 36. Approximately what true airspeed should a pilot expect with 65 percent maximum continuous power at 9500 feet with a temperature of 36 F below standard?

A. 178 MPH

B. 181 MPH

C. 183 MPH

11. Refer to figure 36. What is the expected fuel consumption for a 1000-nautical mile flight under the following conditions?

Pressure altitude- 8000 feet

Temperature- 22 C

Manifold Pressure- 20.8 inches Hg

Wind- calm

A. 60.2 gallons

B. 70.1 gallons

C. 73.2 gallons

12. Refer to figure 36. What fuel flow should a pilot expect at 11000 feet on a standard day with 65 percent maximum continuous power?

A. 10.6 gallons per hour

B. 11.2 gallons per hour

C. 11.8 gallons per hour

13. Refer to figure 36. Determine the appropriate manifold pressure setting with 2450 RPM to achieve 65 percent maximum continuous power at 6500 feet with a temperature of 36 F higher than standard.

A. 19.8 inches Hg

B. 20.8 inches Hg

C. 21.0 inches Hg

14. Refer to figure 41. Determine the total distance required for takeoff to clear a 50 foot obstacle.

OAT- Std

Pressure level- sea level

Takeoff weight- 2700 lb

Headwind Component- calm

A. 1000 feet

B. 1400 feet

C. 1700 feet

15. Refer to figure 41. Determine the approximate ground roll distance required for takeoff.

OAT- 100 F

Pressure altitude- 2000 ft

Takeoff Weight- 2750 lb

Headwind Component- calm

A. 1150 feet

B. 1300 feet

C. 1800 feet

16. Refer to figures 33 and 34. Upon landing, the front passenger (180 lbs) departs the airplane. A rear passenger (204 lbs) moves to the front passenger position. What effect does this have on the CG if the airplane weighed 2690 pounds and the MOM/100 was 2260 just prior to the passenger transfer?

A- The CG moves forward 3 inches

B- The weight changes, but the CG is not affected

C- The CG moves forward 0.1 inch

17. Refer to figures 33 and 34. Which action can adjust the airplanes weight to maximum gross weight and the CG within limits for takeoff?

Front seat occupants- 425 lbs

Rear seat occupants- 300 lbs

Fuel, main tanks- 44 gal

A. Drain 12 gallons of fuel

B. Drain 9 gallons of fuel

C. Transfer 12 gallons of fuel from the main tanks to the auxiliary tanks.

18. Refer to figures 33 and 34. What effect does a 35-gallon fuel burn (main tanks) have on the weight and balance if the airplane weighted 2890 pounds and the MOM/100 was 2452 at takeoff?