spiral


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death spiral

1. In aviation, a dangerous downward cork-screw maneuver of a disabled or uncontrollable aircraft that often leads to a crash. Also called a "spiral dive." The pilot, unaware of the plane's slight roll in the cloud bank, only realized he was in a death spiral when it was too late to overcome the dive.
2. In pairs figure skating, a maneuver in which the male partner, in a pivot position, spins the female partner with one hand in a wide circle with her body nearly parallel to the ground. The two pulled off an amazing death spiral—her head looked as though it were about to touch the ice at one point!
3. In insurance (especially health insurance), a plan in which costs rapidly increase over time due to policyholders with a lower risk opting out of the policy, forcing those dependent on it to pay higher premiums, thus prompting more low-risk policy holders to opt out and further drive up costs, and so on. I purchased my health insurance plan as a means to afford my medicine, but it turned into a death spiral when employers started offering cheaper, barebones plans that the majority of people were quick to switch to.
4. In finance, a loan given by investors to a company in exchange for convertible bonds, which can then be converted to common stock at prices lower than the market value, causing overall share prices to fall and more bondholders to trade their stock for equity, ultimately leading to a collapse of the company's stock worth altogether. To keep his company afloat, Tom was forced to take a loan that ultimately proved a death spiral, leading him to close the business anyway.
5. Any situation in which a series of events or actions, especially as a consequence of one another, ultimately lead to a point of ruin, failure, or destruction. With the recent allegations of drug abuse, corruption charges, and controversial remarks about minorities, the long-time senator now seems locked into an irreversible death spiral.
See also: death, spiral

spiral down

1. To travel down (something) in a twirling or spiraling motion. After the second engine went dead, the plane started spiraling down to the ground. I pulled the plug and watched the water spiral down the drain.
2. Of some measurement or value, to decrease very rapidly. The company's stock prices have spiraled down since the CEO's arrest, dropping nearly 18 points in two days. As the sun set the temperature began spiraling down, so I knew we needed to find shelter soon.
See also: down, spiral

spiral up

To move, proceed, or lead up in a spiral path or motion. The ornate staircase spiraled up to the second floor. The dust spiraled up into the air in a small whirlwind.
See also: spiral, up

spiral down

to descend in a spiral path. The ancient trail spiraled down the mountain peak. A path spiraled down and at the bottom was a small refreshment stand.
See also: down, spiral

spiral up

to ascend in a spiral path. The smoke spiraled up to the sky. The trail spiraled up the slope to the top.
See also: spiral, up
References in periodicals archive ?
Based on this examination, the input impedance of spiral antenna is closely related to the parallel characteristic impedance of two outward-propagating slotline modes with lateral PMC boundaries on spiral structures.
The working principle of a double-arm Archimedean spiral antenna can be explained with current band theory.
Particularly, when UAV is flying in the state of spiral, the nonlinear characteristics will be particularly evident.
Four-arm spiral antenna can be viewed as composed of two spiral arms, these two spiral arms need to be fed from 90 deg of phase.
Spiral heat source model and its analytical solutions
While some younger spiral galaxies have been spotted with barred structures, these formations are more commonly found among older spirals, thus scientists view it as a "sign of galactic maturity." The barred structures are also believed to be centers of star formation since they contain numerous young stars. 
Speyer said, "With its iconic architecture, technological innovations, top-tier amenities, amazing views and abundant access to outdoor spaces, The Spiral is raising the bar for the 21st Century creative work environment."
In this paper, for the first time, we propose the smart utilization of hybrid loading techniques of meandering and tapering, as well as another novel technique of grooving the cavity, to boost the performance of a 2-18 GHz spiral antenna within the smallest form factor (50 mm diameter).
Mineral processing equipment supplier Multotec reported that one of its gravity-separation customers, Northam Chrome Producers, is realizing improved recoveries, better grades and higher yields following the installation of Multotec spirals at its recovery plant.
"Eastern Sheet Metal is one of a select few spiral manufacturers that offer AMCA certified spiral duct," says Patrick Brooks, Eastern Sheet Metal General Manager.
If you make a mistake in a spiral design, chances are you can travel stitch or wiggle your way back out of the area without needing to rip out your mistake.
The Barrel Mill of Avon, MN, a cooperage in Central Minnesota, has introduced a new smaller version of its patented Oak Infusion Spiral that allows home brewers and craft beverage enthusiasts to quickly and easily add barrel-aged flavor, color and aroma directly to the bottle.
As an alternative to the lackluster wheel, the quirky spiral may be the key to forward motion for people who have trouble walking on their own.
In the early 1990s, the first vertical spiral designs made their debut, and were almost immediately recognized as a quantum leap from horizontal helixes, which utilized the efficiency-limiting effects of gravity for tablet transport.
Starfrost has designed and installed a bespoke double drum spiral system at the market-leading soup processor's production facility in the East Midlands.