Variable Value
Mass 500,000 kg
Wing Area 845 m2
Wingspan 79.75 m
Number of Engines 4
CLmax flaps retracted 1.9
CLmax flaps extended 2.6
Oswald Effici
An Airbus A380 is flying in steady, horizontal flight at Flight Level 280.
The pilot reads an Indicated Airspeed (IAS) of 290.0 kts. Calculate the True Airspeed (TAS) in ktsency Factor 0.92
CD0 0.022
To calculate the True Airspeed (TAS), we need to convert the indicated airspeed (IAS) to Calibrated Airspeed (CAS) and then to True Airspeed (TAS) using the following formulas:
CAS = IAS / (sqrt(rho/rho0))
TAS = CAS * sqrt(rho/rho0)
Where:
- IAS is the Indicated Airspeed in knots (kts)
- rho is the density of the air at Flight Level 280 in kg/m^3
- rho0 is the standard density of the air at sea level in kg/m^3
First, we need to calculate the CAS:
rho0 = 1.225 kg/m^3 (standard density at sea level)
rho = rho0 * (1 - (0.00198 * FL))^(5.2561)
where FL is the flight level in hundreds of feet (FL = 280 / 100 = 2.8)
rho = 1.225 * (1 - (0.00198 * 2.8))^(5.2561)
rho ≈ 0.3167 kg/m^3
CAS = IAS / (sqrt(rho/rho0))
CAS = 290.0 / (sqrt(0.3167/1.225))
CAS ≈ 290.0 / 0.5804
CAS ≈ 500.6 kts
Now, we can calculate the TAS:
TAS = CAS * sqrt(rho/rho0)
TAS = 500.6 * sqrt(0.3167/1.225)
TAS ≈ 500.6 * 0.5368
TAS ≈ 269.3 kts
Therefore, the True Airspeed (TAS) of the Airbus A380 at Flight Level 280 is approximately 269.3 knots.