In mining, a windblast is a sudden rush of air or gas due to the collapse of a void.
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Windblast prevention is centred on not allowing the void to form in the first place. This can be somewhat achieved through careful mine planning. Windblast prevention also relies on monitoring to ensure the void does not form (and stopping production if one does begin to form), and the use of different methods to try to promote caving, such as hydraulic fracturing and the use of explosives.
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Windblast should not be confused with an outburst, which is the sudden and violent ejection of rock and gas from a coal seam and the surrounding strata.
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Windblast can also occur in metalliferous, kimberlite or even evaporite mines, particularly in block caving mines, as happened at the Northparkes mine in NSW, Australia on 25 November 1999, killing 4.
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Windblast is common in longwall coal mines, especially those whose roof strata are competent, and do not cave immediately behind the roof supports as the face advances. This results in the tendency for a large void to be created behind the roof supports in the goaf (or gob) which collapses when the overlying cantilevered strata can no longer support its own weight. When the collapse occurs, the air or gas occupying the void is displaced by rock, resulting in a pressure wave and windblast that propagates along the roadways (tunnels) of the mine. This may be followed by a "suck back" as the air pressure is equalised with the low pressure created higher up in the goaf.
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An Air Force Materiel Command investigation found that Cooley momentarily lost consciousness during a high-G maneuver, then ejected when he found himself too low to recover. Cooley was killed during ejection by blunt-force trauma from windblast due to the aircraft's speed. The investigation found no design issues."F-22 Crash Linked To G-Forces".
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The crew sat in tandem, with the flight instructor sitting behind the student on a raised seat to give a good forward view. There was a windblast screen between the two cockpits. The aircrew sat under separate clamshell canopies on Weber ES-7J zero-zero (zero altitude, zero speed) ejection seats, built by Daiseru.Michell 1994, p. 128.
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The CBR600F shares most of the components with the CB600F Hornet naked bike such as inverted fork though longer by and aluminium mono-backbone frame. It is wrapped in a multi-layered full fairing that lowers drag and protects the rider from windblast as well as new instruments, bars and tank. It also retains a similar relaxed seating position to minimise rider fatigue. The 2011 CBR600F also shares the engine of the highly revised CB600F model that came out in April 2007.
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"Bend Time" can be used to slow down time, circumventing dangerous checkpoints or reaching enemies unobserved. The ability "Windblast" enables Corvo to summon a blast of wind that can deflect projectiles and push enemies off ledges. Emily has powers new to the series, including "Far Reach", which allows her to pull objects and enemies toward her and travel without physical movement by clasping onto something to propel herself forward. She can use "Mesmerize" to distract her enemies, moving them into a state of sedation.
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The first parachute, the size of a large handkerchief, was deployed out of a telescoping rod which would pop out of the top back of the seat as it started to clear the windscreen windbreak area. It was supposed to help rotate the seat into the windblast and stabilize into a flight path that would take it above and behind the vertical stabilizer. As the first chute and rod separated from the seat, a larger drogue parachute deployed to slow down the seat, allowing the deployment of the main parachute. If engaged at low altitudes, the seat included a barometric element that allowed the drogue chute to separate more quickly.
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