The Hyperloop design was first conceived in a 2010 white paper by Elon Reeve Musk, a South Africa-born Canadian billionaire inventor who helped found Tesla Motors and SpaceX and described his open-sourced Hyperloop system as a "cross between a Concorde, a rail gun and an air hockey table" for combining subsonic speed
and the levitating ability of air pressure.
In other words, there is a large difference in the autoignition propagation speed between a supersonic speed under a condition where knock intensity increases sharply and a subsonic speed
for a condition where it does not.
An example of an actively illuminated frame that contains a projectile trajectory trail of a projectile traveling at a subsonic speed
Voyager 1 started picking up radio static from the heliosphere's turbulent boundary decades ago, and in 2004 it noted that the solar wind had decelerated to subsonic speed
. In August 2012 the craft relayed that the number of cosmic rays had jumped and the solar wind had plummeted--exactly the effect that space physicists expected to find in interstellar space.
The Hoplite-L multimode seeker allows to discriminate targets in difficult environment; following a high speed transition it dwells thanks to two small wings, allowing target designation for Hoplite-S missiles, before hitting its own designated target with a penetrator that is accelerated by a booster, as in the last phase the Hoplite-L flies at subsonic speed
. Because of the booster, the Hoplite-L is 3,750 mm long and weighs 135 km, compared to the 3,200 mm and 120 kg of the S.
The magnetic "bubble" surrounding Earth also pushes back on the solar wind, creating a bow shock tens of thousands of miles across over the day side of Earth where the solar wind slams into the magnetic field and abruptly slows from supersonic to subsonic speed
Twenty Russian-made BM-21 rockets are heading towards the Type 42 Destroyer at subsonic speed
and in near darkness on Liverpool's bridge, sailors peer through binoculars and into complex screens, tracking the Libyan shells and urgently tracing the BM-21 firing points.
The gruesome missile opens up as it screams towards the target zone and the darts are blasted out at subsonic speed
When the design of the three sections is logical, the uniform flow obtains subsonic speed
, velocity of sound, and supersonic speed through the convergent, throat, and divergent, respectively.
"In order for a turbojet to run properly, air must arrive at the engine face at a relatively low, subsonic speed
. Also, engines function less efficiently with a turbulent air supply, so the inlet system has to deliver smooth flow to the engine.
The Beijing University of Aeronautics and Astronautics developed the Chang Hong UAV--a high altitude, high subsonic speed
, multi-role aircraft.
Malaysian specialists reportedly determined that the Su-30MKIM is better in air-to-air engagements than the F/A-I 18E/F but inferior in ground-attack capabilities, due primarily to the Su-30MKM's lack of GPS-guided bombs and other sophisticated air-to-ground weapons, though the Kh-31A is deemed far more effective than the AGM-84D Harpoon - e.g., supersonic versus subsonic speed
, greater range, and better resistance to electronic countermeasures (ECM).