This page needs to be proofread.

DICTIONARY OF AVIATION 199

air, as an aeroplane flyer does, or seems to do, tuhen net

wholly under the control of the operator.

2. move along en a skid or en skids, as a flying^machine

does in landing; slide en the landing^skids or runners. skid-strut 'skid,stAt n. one of the struts or braces of the

landing^skid of a flymg^machine. skid-wheel 'skid,iuiil n. one of the landmg#u>heels attacht

to or taking the place of a skid in a flying^machine. skim skim v.

1. glide aleng upen; soar close to.

2. glide or dart aleng in a smooth even course thru the air; soar.

skimmer 'skimaz n. a bird that skims or shears the water, as any member of the genus rhyncheps; a cutwater, shear- water, or scissorbill.

skin-area 'skm,e:-zi-a n. the area of the portion of the sur- face of a selid bedy which is immerst in a fluid.

skin-fold 'skm^oold n. the fold or fly in the skin forming the patagium or flymg^membrane of a flying animal : as, the *skin?fold of the flying^squirrel.

skin-friction 'skin,fsik$9n n. [also spelt skin friction] the friction between the skin or immerst surface of a selid bedy and a fluid, such as the air, in which the selid bedy is immerst and thru tuhich it is moving; skm^resistance.

skin-frictional 'skin,f5ik$9-nl adj. ef or related to, skin* friction : as, the influence of *skins:frictionai error.

skin-resistance 'skm-zi,zistns n. the resistancce efferd to the air or other fluid by the skin or surface of a moving aerof eil ; skm^f riction.

sky skai n. [ploral skies'] the region of clouds; cloudland; the hevens ; the firmament : ef ten used in the ploral : as, to sail the *skies.

clear sky, a sky markt by the absence of clouds; the sky characteristic of a clear day; specifically, in the United States Wether^Bureau, a sky in tuhich the obscuration is about 3 en a scale of 10.

green sky, a sky which is green in color, usually occur- ring at sunset.

lamb'sfwool sky, a sky characterized by white fleecy patches of cloud against the blue.

livid sky, a sky overspred by clouds of a livid hue; a blackish^blue or leden sky.

mackerel sky, same meaning as mackerelzsky. red sky, a sky which is red in color, usually occurring at sunset.

�� �