rudder ball 200
rudder ball /'rAd. b.:l/ noun same as inclinometer rudder pedal /'rAd. ， ped (.)l/ noun a
foot-operated lever which moves the rudder 0 Just before take-off, the pilot should make sure that his or her feet are correctly positioned on the rudder ped-als.
rule /ru:l/ noun 1. a standard and authoritative instruction  guide 0
According to the rules, your ticket must be paid for two weeks in advance.口 as a rule usually 0 As a general rule, radio signals travel in straight lines. 2. an instrument for determining length
rule of thumb /，ru:l .v 'θAm / noun
easily remembered, useful guide to a
more complex principle run /rAn/ noun a route or distance _ verb 1. to extend 0 Magnetic lines of force run from the north magnetic pole to the south magnetic pole. 2. to operate an engine 0 An engine should be run at low r.p.m. (revolutions per minute) after flight to allow engine components to cool to a more uniform temperature.
run up /，rAn 'Ap / noun口 engine run-up the testing of a piston engine at high power, in a light aircraft, just before take-off 0 Make certain that the parking brake is on before doing engine run-up checks.