IADG Airbus A319

Flight Dynamics Information

General

This flight dynamic file (*.air) is intended to be used with the family of Airbus A319 available from Int'l Aircraft Design Group (www.flightsimnetwork.com/IADG).

For these FDX files I have used published data by Airbus and excerpts from an aircraft operating manual. The basis is an A319-100 with 75% load factor, as it is typical for short range, scheduled flights. You can refuel it up to 100% without exceeding maximum take-off weight in case you want to make longer distances.

As Airbus offers a large variety of engines and fuel capacities, I had to decide on a specific configuration.

Aircraft data and design criteria

This table contains the most important data, which were used to design the flight dynamic model.

Aircraft data

Unit

Unit

Wing span

m

34.1

ft

111.8

Length

m

33.8

ft

111.0

Height

m

11.8

ft

38.6

Wing area

m2

122.6

sqft

1320.0

Dry weight empty

kg

40,100

lb

88,405

Passengers max.

124

124

plus luggage (total 90 kg)

kg

11,160

lb

24,605

Design Freight

kg

880

lb

1,940

Design ZFW 75% load

kg

49,350

lb

108,800

Fuel max.

l

23,860

gal

6,300

kg

18,870

lb

41,600

Fuel 75%

kg

14,150

lb

31,195

Design TOW 75% load

kg

63,500

lb

139,990

MTOW

kg

68,000

lb

149,910

Design Trust

kN

113.4

lb

25,500

Cruise TAS

mach

0.78

mach

0.78

Maximum TAS

mach

0.82

mach

0.82

Take off and climb

There are many ways to reach the desired flight level. The following procedure and table is an example with 7.7 tons of fuel (main wing and aux. tanks 62%, center tank empty) totaling to 57.0 tons TOW. This is a typical TOW for a one to one and a half-hour flight. It is intended as a guideline for needed time, distance and fuel consumption up to typical flight levels.

The real Airbus thrust levers have a notch for climb settings called CL. With trust levers set at that notch, the engine control sets N1 to the optimum under the current condition of gross weight, outside temperature and altitude.

For standard weather conditions it is about 90% N1 on ground and increases continuously to values of 95% and above at high altitude. You may take off with this setting if weight and runway conditions do allow for it. Hot outside temperatures, high altitude or short runway may require the initial take off setting to be above 90%.

Initial pitch is 17° for low GW and 14° for high GW and at "acceleration altitude" equal 1500" AGL pitch is reduced to 10° and thrust levers are set to CL. Passing 175 KIAS flaps are set to zero and the plane accelerates with moderate climb rates. Reaching stable conditions you may activate the AP. Reaching 250 KIAS , the climb rate will be increased to maintain 250 KIAS below FL100. By that you reach quickly FL 100 and by then reducing climb rate you want the plane to accelerate to 280 KIAS which is the best climb speed for that plane. This speed is maintained until you reach the desired flight level. At high altitudes you man need to limit it to maximum cruise speed of mach 0.78.

FS does not simulate the automatic climb control of Airbus - N1 and V constant and controlling climb rate. Therefore the climb rate must be manually reduced to maintain 280 KIAS during climb. Having set the thrust lever to 88% N1 at acceleration altitude, you can leave it unchanged and N1 will slowly increase to safely reach high altitude cruise levels.

Standard flight

FOB

FOB

GW

CT

WT

AT

40%

7,650 kg

57.0 t

0%

62%

61%

Flaps

Vr

V2

Climb

pitch

trim

F1+F

127

137

160/+3000

17°

0.5

Flaps

IAS

CR

pitch

N1

Fuel cons.

Time

Distance

1500"AGL

F1+F

160

+3000

17°

92%

5000" TA

F0

240

+2500

10°

88%

FL100

F0

250

+3200

10°

89%

430

3' 30"

10 NM

FL150

F0

280

+2400

6.25°

90%

620

5' 40"

23 NM

FL200

F0

280

+1800

92%

800

8' 15"

37 NM

FL250

F0

280

+1200

3.75°

93%

1,020

11' 45"

60 NM

FL 300

F0

280

+800

3.75°

94%

1,280

17' 00"

95 NM

FL 330

F0

280

+600

2.5

94%

1,480

22' 00"

120 NM

FL 350

F0

0.78

+600

2.5

94%

1,620

25' 20"

160 NM

Cruise

The following table is similar to the standard cruise recommendations of the Airbus AOM for an A319 with 65 tons gross weight. My design point is FL 270 with mach 0.75. Above and below that design point the values deviate in FS from the AOM but the magnitude is correct. The last line is the engine settings for maximum speed of mach 0.82 at FL 350.

FS Cruise

N1

FF

FL 200 / 0.65

77.3%

1,480 kg/h/e

FL 270 / 0.75

84.1%

1,350 kg/h/e

FL 310 / 0.78

88.0%

1,220 kg/h/e

FL 350 / 0.78

91.1%

1,000 kg/h/e

FL 350 / 0.82

95.3%

1,360 kg/h/e

Descent and landing

Out of cruise level you can descent with max. -3500 ft/min with idle thrust and about 300 KIAS. In case of an emergency, sink rates of -6500 ft/min are possible with full speed brakes set. Below FL 100, sink rates should not exceed -1800 to -2000 ft/min, but may be changed due to ATC requirements.

The following table gives you Minimum Maneuver Speeds.

FS Minimum Maneuver Speeds

FL 50

FOB

FOB

GW

CT

WT

AT

Level off

20%

3650 kg

53 t

0%

33%

0%

Approach

Flaps

IAS

N1

FF

pitch

trim

Conf. 0 / O speed

F0

191

46.0%

820 kg/h/e

6.25°

2.7

Conf. 1 / S Speed

F1

175

50.3%

970 kg/h/e

2.6

Conf. 2

F2

144

56.0%

1140 kg/h/e

6.25°

2.6

Conf. 3 / VLS+10

F3

134

58.6%

1220 kg/h/e

6.25°

2.4

Conf. 4 / VLS+10

F4

128

60.9%

1300 kg/h/e

2.1

Having calculated fuel consumption correctly, you would aim to reach your destination airport with 3 to 4 tons FOB depending on the distance to alternative airport. The following would be a standard ILS approach procedure. Arriving faster and/or heavier at glideslope intercept may require using speed brakes to slow down during the descent. Standard landing is with F4 and VLS+10.

FS Landing

FOB

FOB

GW

CT

WT

AT

20%

3650 kg

58 t

0%

33%

0%

Flaps

IAS

N1

FF

pitch

trim

Approach level off

F0

250

53.1%

1170 kg/h/e

3.75°

1.7

green dot - set F1

F0

191

46.0%

820 kg/h/e

6.25°

2.8

Intercept GS

F1

190

51.8%

1040 kg/h/e

2.3

GS established

F2

170

43.3%

780 kg/h/e

-1.25°

2.0

GS slow down

F3 GD

149

50.2%

1010 kg/h/e

2.7

GS VLS+10

F3 GD

134

49.5%

980 kg/h/e

2.5°

3.2

GS VLS

F3 GD

124

49.2%

970 kg/h/e

3.8

GS slow down

F4 GD

139

50.4%

1090 kg/h/e

2.5

GS VLS+10

F4 GD

128

50.0%

1070 kg/h/e

2.5°

3.0

GS VLS

F4 GD

118

50.1%

1060 kg/h/e

3.6

To avoid air pollution and noise, standard landing uses wheel brakes (autobrake low) and reverser set with idle thrust - just to have a little negative acceleration force supporting the wheel brakes. Only on short runways, late touchdown, still a lot of fuel on board or wet/snow surface, reverse thrust is applied.

Epilog

There should be no entries necessary under [TUNING] in the aircraft.cfg as this aircraft behaves very much like the real one.

Feedback on your experience and recommendations for upgrades are always welcomed. Please use the IADG forum for such purpose.

Happy landings!
Alexander M. Metzger/IADG