Page:Dictionary of aviation.djvu/97

 DICTIONARY OF AVIATION 73

lurreted cumulus, a large cumulus cloud having turretelike covers the sky in the regions of the tjadewinds.

trade cumulus, a kind of small detacht cloud which often masses rising from its tep; a thundercloud.

ocean current, a current or stream in the water of the air.

cumulus-like 'kgumjofos^aik adj. like cumulus cloud; re- sembling cumulus.

curl-cloud 'kB:zl,kz,aod n. cirrus; cat's^tail. current 'kezant n. that tuhich flows; a stream; a portion of a body of air moving in a defmit direction; an air* current.

ascending current, a current of air which is ascending or rising; a rising current.

convectional current, see under convectional.

downthrow current, an air^current which has a down- ward throw or tjend; a falling or descending current of ocean, such as the Gulf Stream.

upper currents, the currents or motions high up in the air.

curtain 'keztn n. an aerofoil placed vertically, as between the main supportmg^surfaces of some biplanes; a vertical surface in a cellular or bex^kite structure; a panel; a par- tition. curve 'kerzv n. [also spelt curv]

curve of torque, a plotted curv, or curvd line, showing the relation between the torque or tuuistingsforce acting en a propeller and the thrust or the speed of revolution of the propeller.

inflected curve, a fugeid curv of the inflected type.

tumbler curve, a fugeid curv of the type characteristic of the tumbler pigeon.

cusp kAsp. a peint or apex; a peint at u)hich two branches of a curv meet and step, with a cemmon tangent; a point at luhich the moving peint describing a curv has its motion exactly reverst; also, an analogous point en a curvd surface; a spinode; a stationary point.

custom 'kAstam n. a tjibute, toll, impost, or duty, levied by a national or local authority upon the entry of commodi- ties or goods into his dominion; a duty levied en imports; an imporfcftax.

cut-air 'kAt,e:z n, a rigid shield at the front of an airship, or a rigid edge on an aeroplane or wing, so shaped as to cut or plow thru the air and thus reduce the atmosfenc re- sistance to motion.

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