noticeable 158
doing the pre-flight checks, Captain Smith noticed that there was a leak of hydraulic fluid from one of the brake cylinders.
noticeable /n.υt.s.b(.)l/ adjective
catching the attention, easily noticed . a noticeable increase an increase which is important enough to be observed .
There was a noticeable improvement in the trainee’s recent exam results.
notice board /n.υt.s b.d/ noun a
usually wooden board in a corridor or classroom, etc., where information on paper can be displayed
notification /n.υt.f.ke..(.)n/
noun the act of informing somebody about something . Notification of the new procedures will follow in a few days. . She received notification that she had been accepted for the job.
notify /n.υt.fa./ verb to inform . Stu-
dents were notified of their exam results by post. . The authorities must be noti-fied of all in-flight incidents.
nozzle /n.z(.)l/ noun a projecting part with an opening at the end of a pipe, for regulating and directing a flow of fluid . The nozzle of a portable fire
extinguisher should be pointed at the base of the fire.
nucleus /njukli.s/ noun the central part around which other parts are grouped . An atom consists of a nucleus with orbiting electrons. . Condensation occurs on very small particles sus-pended in the air which are known as condensation nuclei. (NOTE: The plural form is nuclei.)
null /nl/ noun an instrument reading of zero . the null position the zero position . Nulls are used for direction sensing because they are better defined than the maxima.
numerical /njumer.k(.)l/ adjective
referring to numbers or digits
numerical value /njumer.k(.)l vlju/ noun a number numerous /njum(.)r.s/ adjective
very many, a lot . Large transport air-craft have numerous clearly-marked exits to facilitate rapid evacuation of passengers. . Numerous refinements to the simple actuator will be found in use.
nut /nt/ noun a metal ring which screws on a bolt to hold it tight . Turn the nut anticlockwise to loosen it.

O

OAT abbreviation 1. operational air
traffic 2. outside air temperature obey /.be./ verb 1. to carry out or comply with a command . Pilots must obey landing instructions. 2. to follow a physical law . Winds obey Buys Ballot’s Law.
OBI abbreviation omni-bearing indica-
tor object /.bdekt/ noun 1. something that you can touch and see and that has a particular form and dimensions . Any given object will collect more ice when travelling at high speed than at low speed. 2. intention or aim . The object of the briefing is to inform all aircrew of the new procedures. . verb /.bdekt/ to raise or voice opposition . Staff objected to the introduction of longer working hours.
oblong /.bl../ adjective rectangular . an oblong piece of aluminium . noun