1Dk4eXg

independent overspeed protection
2 R&D or programme not relying on external funding.
3 Airline run by private company.
independent overspeed protection Gas-turbine engine
subsystem independent of the EEC or other control which
automatically shuts the engine down upon sensing rotor
overspeed.
indexed wing/fins Aerodynamic surfaces are at same
angular setting to [usually missile] body, measured in
transverse plane, eg all at 45° to horizontal or two vertical
and two horizontal.
index error That caused by misalignment of measurement
mechanism of instrument (ASCC).
Indian Hostile aircraft, esp. fighter.
indicated airspeed See airspeed.
indicated altitude That shown by altimeter set to latest
known QNH.
indicated course Locus of points in any horizontal plane
at which ILS Loc needle is centred.
indicated course sector Sector in any horizontal plane
between loci of points at which ILS Loc needle is at FSD
left or right.
indicated glidepath Locus of points in vertical plane
through runway centreline at which G/S needle is centred.
indicated hold Autopilot mode maintaining present IAS.
indicated horsepower Theoretical power developed by a
reciprocating engine, ignoring losses due to friction,
windage and other causes, numerically proportional to
PLAN where P is the brake mean effective pressure, L is
the piston stroke, A total piston area and N the rotational
speed, all units being compatible. See horsepower.
indicated Mach number That shown on Machmeter.
indicator Identifying 4-letter code for every airfield [in
England and Wales beginning EG].
indicator diagram Plot of piston engine cylinder pressure
against piston position, often drawn by instrument
attached to cylinder.
indirect air support Given friendly land/sea forces by
action other than in tactical battle area, eg by interdiction
and air superiority.
indirect cycle Nuclear propulsion with primary circuit,
heat exchanger and secondary circuit.
indirect damage assessment Revised target assessment
based on new data such as actual weapon yield and
ground zero.
indirect wave One arriving by indirect path caused by
reflection/refraction.
indium In, soft silver-white metal, density 7.28, MPt
156.4°C.
individual controls Control surfaces not attached to
fixed surface but cantilevered from body (guided
weapons).
induced downwash angle Loosely called induced angle,
the downwash angle at any radius of a propeller blade due
to lift, one symbol, being ε i .
induced drag Drag due to component of wing resultant
force along line of flight; drag due to lift. For a conventional
wing in subsonic flight C Di = C 2 L / πAe where e is
an efficiency factor very close to unity.
induced flow Fluid flow drawn in and accelerated by a
high-velocity jet.
induced force Usual aircraft design consideration is that
caused by air entering engine inlet.
induced velocity That due to wing vortex system and
downwash, normally considered proportional to lift.
inerting
inducer 1 Booster vanes at entry to centrifugal impeller,
esp. rocket-engine turbopump.
2 Bleed ejector to induce cooling airflow.
inductance Property of electric circuit to resist change in
current as result of opposing magnetic linkage; see self *,
mutual *.
induction 1 In a piston engine, sucking in air or mixture
on downstroke.
2 In the overhaul process [of anything], accepting the
item, plus documentation, into the overhaul facility.
induction compass Based on induction coil pivoted to
rotate in Earth’s field.
induction heating Heating electrically conductive
material by h.f. field.
induction manifold Pipe system conveying mixture to
piston engine cylinders.
induction period Specified delay between adding catalyst
or hardener and applying or spraying material (coating,
adhesive or thermo-setting structure).
induction phase In pulsejet, portion of cycle when air is
admitted.
induction stroke In piston engine, portion of cycle when
air or mixture is admitted.
induction system In piston engine, entire flow path from
combustion-air inlet to cylinder.
induction tunnel Wind tunnel driven by jet engine(s) or
compressed air via ejector system.
inductive coupling 1 Mechanical shaft drive relying on
magnetic linkage.
2 Magnetic coupling between primary and secondary
coils, eg of transformer.
inductive reactance Impedance due to inductance.
inelastic collision Theoretical impact with no deformation
or energy loss.
inert gas Gas incapable of chemical reaction.
inertial anti-icer Free-spinning vanes or other device for
imparting rotation to engine airflow, ice or snow being
flung out away from engine inlet.
inertial coupling See coupling (1).
inertial flight No propulsion, controls locked central or
free.
intertial frame A reference frame subject to Newton’s
Laws.
inertial guidance Guidance by INS.
inertial gyro Gyro of characteristics and quality to meet
INS requirements.
inertial navigation system, INS Assembly of superaccurate
gyros to stabilize a gimballed platform on which
is mounted a group of super-accurate accelerometers –
typically one for each of the three rectilinear axes – to
measure all accelerations imparted, which with one automatic
time integration gives a continuous readout of
velocity, and with a second time integration gives a
readout of present position related to that at the start.
inertial orbit Trajectory when coasting.
inertial platform Rigid frame stabilized by gyro(s) to
carry accelerometer(s).
inertial restraint Of a structural beam, free at one end
but with an attached mass which damps movements.
inertia starter Rotary-drive starter whose energy is
stored in flywheel.
inertia welding Welding by rapid rotation and pressure
between mating surfaces.
inerting Filling the space above the fuel in a tank with
344