1Dk4eXg

endurance
endurance Maximum time aircraft can continue flying
under given conditions without refuelling.
endurance limit Highest structural stress that permits
indefinite repetition or reversal of loading; always less
than yield stress (see fatigue limit).
endurance on station Maximum time maritime aircraft
can patrol in designated areas.
ENEC Extendable nozzle exit cone.
Enema Etablissement National pour l’Exploitation
Météorologique et Aéronautique (Algeria).
energy Capacity to do work. SI unit = joule, or [more
usefully] MJ = 0.3725 hp-h, 0.277· kWh; 1 kWh =
3.6000 MJ; 1hp-h = 2.68452 MJ; 1 hp-h = 2.68452 MJ; 1
therm = 105.506 MJ; 1 BTU = 1.05506 kJ. At any time *
of a flying vehicle is given by E h = W (h + V 2 /2 g ) where h
is height above MSL and W is instantaneous mass.
energy absorption test See drop test.
energy conversion efficiency Ratio of kinetic energy of
jet leaving nozzle to that of hypothetical ideal jet leaving
ideal nozzle using same fluid under same conditions.
energy density Sound energy per unit volume (usual unit
is non-SI: ergs/cc).
energy footprint Total area of damage caused by aircraft
crashing, especially at airshow.
energy height A measure of kinetic and potential energy
of an air vehicle; h e = h + V 2 /2 g where h is altitude above
MSL and V is TAS expressed as a velocity.
energy level Any specific value of energy which a particle
may adopt; during transitions from one level to another,
quanta or radiant energy are emitted or absorbed,
frequencies depending on difference between levels.
energy management Monitoring to minimise fuel expenditure
for trajectory control, navigation, environmental
control, etc.
energy manoeuvrability Flight manoeuvres in which full
use is made of kinetic energy of aircraft, normally in
trading speed for altitude.
energy state Total kinetic plus potential energy
possessed by aircraft, particularly a fighter; normally
expressed as altitude from SL reached (without propulsion)
if all such energy were converted to potential
(height) energy.
energy weapons See directed-energy.
ENG Electronic news-gathering.
Eng Engine.
Engage Armed position of some arrester hooks,
extended or hinged down prior to landing
engage 1 In air interception, order to attack designated
contact (DoD usage).
2 To contact arrester wire or barrier.
engage and trim indicator Panel instrument showing
proper engagement of ailerons/elevators/rudder to
autopilot system.
engagement Encounter which involves hostile action by
at least one participant.
engagement control Exercised over functions of airdefence
unit related to detection, identification,
engagement and destruction of hostile targets.
engaging speed Speed of aircraft relative to arrester wire
at engagement.
engin Missile (F).
engine altimeter Indicates altitude corresponding to
manifold pressure of supercharged engine.
engine-attributable Caused by fault in an engine.
enhanced GPWS
engine car Airship car wholly or mainly devoted to
propulsive machinery.
engine change unit Aircraft piston engine removable as
single unit with all accessories, cooling and oil systems.
engine cowling Hinged or removable covering around
aircraft engine shaped to keep drag to minimum and optimise
flow of cooling air.
engine critical part[s] Part[s] whose failure is likely to
cause a Hazardous Engine Effect.
engineered material Cellular concrete for overrun areas.
engineering 1 Department responsible for detail design
and development.
2 Hardware design and development.
engineering mock-up Full-scale replica of new aircraft or
major part thereof, made [usually in metal] with
high precision, partly in hard tooling, to check threedimensional
geometry of structure, systems, and
equipment.
engineering time Number of man-hours required to
complete engineering task.
engineering units Pre-SI (suggested obsolete) system of
units for expressing lift and drag of wing or component
part in lb/sq ft at 1 mph at specified angle of attack.
engine-failure recognition speed Usually written V frr .
engine flight cycle The flight profile upon which the
Approved Life is based.
engine icing A problem with all engines, but especially
with piston engine with a choke-tube carburettor, where
temperature is sharply reduced.
engine indication and crew alerting Eicas monitors
several [typically 12] measures of engine and system
performance, and can indicate impending failure.
engine mounting Structure by which engine is attached
to airframe.
engine-out Condition in which one engine of multiengined
aircraft gives no propulsive thrust.
engine-plus-fuel weight A criterion of propulsive
efficiency, heavy engines generally burning less fuel.
engine pod See pod.
engine positioner Dolly or trailer designed to carry
engine, especially large turbofan, on cradle provided with
hydraulic, or electrohydraulic, lateral, vertical, fore/aft,
roll and pitch movement.
engine pressure ratio Pressure ratio across complete
compression system [possibly fan, booster and LP, IP and
HP compressors]. In 1950 an axial spool of 15 stages
achieved * of about 6; today this number of stages can
exceed 50.
engine rating Power permitted by regulations for
specified use; maximum takeoff, combat, maximum
continuous, weak mixture etc.
engine-section stator The ring of inlet guide vanes immediately
downstream of a fan at the inlet to the core.
engine speed Revolutions per minute of main or other
specified rotor assembly.
engine swapping Replacing engines due for overhaul
with stored engines that have serviceable life remaining.
English bias Missile aiming error at launch, and temporary
guidance commands to overcome it.
EngO Pronounced N-jo, Engineer Officer (RAF).
ENH Earth near horizon.
enhanced GPWS Uses aircraft flight data to calculate
envelope along projected flight path and compare this
with internal terrain data base. Potential conflict gives
233