Crossword clues for skyhook
Douglas Harper's Etymology Dictionary
Wiktionary
n. An hook imagined to be suspended in midair.
WordNet
n. helicopter carrying a reel of steel cable that can be used to lift and transport heavy objects
a hook that is imagined to be suspended from the sky
Wikipedia
Skyhook, sky hook or skyhooks may refer to:
In skateboarding and related sports, skyhooks are devices which serve as semi-open bindings. They are usually made of aluminium, steel or hard plastic and are formed to cover the rider's boot, yet to allow him to easily free his feet from the hook. They may be screwed to the top of the board to facilitate jumping and enhance stability during a ride.
They are mostly used on freeboards and longboards without a kicktail.
A skyhook is a proposed momentum exchange tether that aims to reduce the cost of placing payloads into space. A heavy orbiting station is connected to a cable which extends down towards the upper atmosphere. Payloads, which are much lighter than the station, are hooked to the end of the cable as it passes, and are then flung into orbit by rotation of the cable around the centre of mass. The station can then be reboosted to its original altitude by electromagnetic propulsion, rocket propulsion, or by deorbiting another object equal in mass to the payload.
A skyhook differs from a geostationary orbit space elevator in that a skyhook would be much shorter and would not come in contact with the surface of the Earth. A skyhook would require a suborbital launch vehicle to reach its lower end, while a space elevator would not.
The Skyhook is United Parachute Technologies version of a Main-Assisted Reserve Deployment system (MARD), a safety feature on skydiving parachute systems. It builds on the concept underlying an ordinary reserve static line (RSL), which uses the force of the departing main parachute to open the reserve parachute compartment after the malfunctioning main parachute is cut-away, by further using the force of the departing main parachute to extract the reserve parachute out of the reserve compartment. This greatly decreases the time, and hence loss of altitude, required to fully open the reserve parachute.
The Skyhook system is engineered so that it should not interfere with reserve deployment activated by directly pulling the reserve rip cord in situations where no main parachute had been deployed. The key component in the system, from which the Skyhook derives its name, is a cantilevered hook that grasps the reserve bridle about midway between the reserve pilot chute and the bag containing the packed reserve chute. If the departing main parachute applies more pull force on the bridle than the reserve pilot chute, then the main parachute will remain hooked onto the reserve bridle, and so it will pull the reserve parachute out of the reserve compartment. If the reserve pilot chute exerts more pull force on the bridle than the main parachute, then the main parachute will unhook and the reserve pilot chute will deploy the reserve parachute normally.
The primary advantage of the Skyhook system over traditional RSLs is a higher reserve deployment after a cutaway. More altitude means more time for the skydiver to perform a safe landing, which is especially important because most malfunctions cause a significant loss of altitude. Since the Skyhook relies on a cutaway main, it offers no advantages in situations where the main parachute has not been deployed from the parachute container.
The Skyhook system can also cause complications. One such incident was captured on video, where a spinning main caused a Skyhook to severely twist the reserve. A standard RSL or manual reserve pull would have taken longer to deploy—but a reserve pilot chute would have pulled the reserve freebag upwards, rather than spinning and entangling it. Due to the increased risk of spinning malfunctions, the use of Skyhooks with high-performance canopies remains an active area of discussion.
An important component of a Skyhook system is the Collins Lanyard, which cuts away the left parachute riser in the event of the right parachute riser releasing. This is important because the Skyhook RSL is activated by the right hand side riser releasing.
The Skyhook was developed by the founder of United Parachute Technologies, Bill Booth. It was originally only available on Vector III parachute containers. Now it is being licensed to other manufacturers, Sunpath being the first licensee to market.
A skyhook is a "hook" used to lift an object on a long cable hanging from the sky, without readily apparent support. In the mid-20th century it was common in the Boy Scouts and occupations such as oil drilling to send new recruits on a futile search for such an imaginary object, as a practical joke. The term has subsequently lent its name to some real mechanisms that use an airborne hook or hoist, and to other products or ideas that allude to the concept. The American philosopher Richard Rorty uses the term to refer to a hypothetical metaphysical system that leads to a universal perspective.
Usage examples of "skyhook".
The best we could hope for, if the Skyhook does not arrive, is to remove some of the more vital systems from the airframe, then destroy it.
Skyhook does not arrive before the deadline expires - you will destroy the airframe completely.
Like the jobbers who flocked to the Moon and the Maldives when Lunar City and the Skyhook had to be built .
I was ready to board the Deimos skyhook, and believe me, I had to take a big loss as a result.
It was the Deimos skyhook, and the nacelle was one of the starport terminals that hauled passengers and cargo up to the little potato moon, 12,500 miles overhead.
Even the east-west and west-east mail satellites, which dropped their own skyhooks from orbits a little above, or below, synchronous orbit, were constrained to an equatorial run.
Theoretical models formulated of space elevators prior to the discovery of the Kharzh’ullan system relied upon ungrounded skyhooks that reached into the upper atmosphere, space tethers, or extensive cabling systems to counteract the gravitational effects a structure the size of an elevator would experience.
Luke saw the giant Star Destroyer's powerful beam strobe, saw it pierce the skyhook.
Skyhooks were, if not the most incredible of human engineering marvels, then certainly the most spectacular.
It's solar sail material harvested from the skyhook tree's leaves.
Several skyhooks have unfurled in equatorial orbit around the earth like the graceful fernlike leaves of sundews, ferrying cargo and passengers to and from orbit.