1 // pitot.cxx - the pitot air system.
2 // Written by David Megginson, started 2002.
4 // This file is in the Public Domain and comes with no warranty.
7 #include <Main/fg_props.hxx>
8 #include <Main/util.hxx>
11 PitotSystem::PitotSystem ()
15 PitotSystem::~PitotSystem ()
22 _serviceable_node = fgGetNode("/systems/pitot[0]/serviceable", true);
23 _pressure_node = fgGetNode("/environment/pressure-inhg", true);
24 _density_node = fgGetNode("/environment/density-slugft3", true);
25 _velocity_node = fgGetNode("/velocities/uBody-fps", true);
26 _total_pressure_node =
27 fgGetNode("/systems/pitot[0]/total-pressure-inhg", true);
36 PitotSystem::unbind ()
41 PitotSystem::update (double dt)
43 if (_serviceable_node->getBoolValue()) {
44 // The pitot tube sees the forward
45 // velocity in the body axis.
46 double p = _pressure_node->getDoubleValue();
47 double r = _density_node->getDoubleValue();
48 double v = _velocity_node->getDoubleValue();
49 double q = 0.5 * r * v * v; // dynamic pressure
50 _total_pressure_node->setDoubleValue(p + q);