The NASA X-43 was an experimental unmanned hypersonic aircraft. It is the fastest aircraft on record...

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The NASA X-43 was an experimental unmanned hypersonic aircraft. It is the fastest aircraft on record with a top speed of Mach 9.6. A NASA engineer working on the X-43 is testing the accuracy of a Pitot probe mounted on the aircraft. Flight conditions correspond to an altitude of 30 km with static conditions T = 231.24 K and P = 1185.5 Pa. NASA 24 a. (10 points). If the aircraft's characteristic length is 4 m, can we assume that continuum assumption holds? Hint: Molecular weight of air is 0.029 kg/mol, Avogadro number N₁ = 6 x 1023 mol', effective cross-section for air molecules (N₂ or 0₂) σ = 10-¹9 m². Start by calculating the mean free path of molecules at the given flight conditions. b. (10 points). A test is carried out at Mach 0.6. The engineer records a Pitot measurement of 0.015 atm. Is the probe measurement accurate? Support your answers with calculations. You may neglect aerodynamic effects from the aircraft. Assume the flow to be isentropic. Reminder: Pitot tube measures stagnation pressure. The NASA X-43 was an experimental unmanned hypersonic aircraft. It is the fastest aircraft on record with a top speed of Mach 9.6. A NASA engineer working on the X-43 is testing the accuracy of a Pitot probe mounted on the aircraft. Flight conditions correspond to an altitude of 30 km with static conditions T = 231.24 K and P = 1185.5 Pa. NASA 24 a. (10 points). If the aircraft's characteristic length is 4 m, can we assume that continuum assumption holds? Hint: Molecular weight of air is 0.029 kg/mol, Avogadro number N₁ = 6 x 1023 mol', effective cross-section for air molecules (N₂ or 0₂) σ = 10-¹9 m². Start by calculating the mean free path of molecules at the given flight conditions. b. (10 points). A test is carried out at Mach 0.6. The engineer records a Pitot measurement of 0.015 atm. Is the probe measurement accurate? Support your answers with calculations. You may neglect aerodynamic effects from the aircraft. Assume the flow to be isentropic. Reminder: Pitot tube measures stagnation pressure.

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a For an aircraft with a characteristic length of 4 meters the continuum assumption is typically va... View the full answer