1Dk4eXg

parallel ILS
parallel ILS Serving parallel runways, with minimum
lateral separation of 1,500 m, 5,000 ft.
parallel-line design Aircraft whose wing LE/TE, tips
and sharp edges are all parallel. This concentrates radar
signature into very narrow beams, easily missed by
enemy. B-2 is example.
parallel offset Airway R-Nav route running alongside
designated airway.
parallel of origin Parallel of latitude used as an origin (2).
parallel redundancy Addition of channels in parallel (3)
mode purely to increase redundancy (1).
parallel resonant circuit Tuned circuit with inductive
and capacitive elements in parallel (3).
parallel runways Runways at same airport on same
alignment and with sufficient lateral separation to permit
simultaneous use, including parallel ILS approaches.
Designators have suffix L or R [left or right] thus 28L is
south of 28R.
parallel servo One located in control system so that
servo output drives in parallel with major input; usually
arranged to drive both cockpit controls and flight-control
system and thus performing as alternative to pilot.
parallel warfare Use of a sensor network and EBO to
render an enemy helpless (USAF).
parallel yaw damper One connected direct into
pilot/rudder control loop and, in some cases, resulting in
movement of cockpit pedals. Normally superseded by
series damper.
paramagnetic Possessing magnetic permeability above 1
and permanent magnetic moment; atoms tend to align in
direction of external field giving resultant magnetic
moment and tend to move to strongest part of field.
Paramatta Code for RAF WW2 blind target-marking
by PFF using precision-aimed TIs of sophisticated types
repeated at intervals; usual form with electronic aids
called Musical *.
parameter Basic definable characteristic or quality, esp.
one that can be expressed numerically; specialized meanings
in maths, EDP (1) and statistics.
parametric amplifier Reactance amplifier dependent on
time-varying reactance (fed by signal and a pump source)
forming part of tuned circuit; variable-capacitance
usually Varactor or crystal diode. Also called Mavar
(mixed amplification by variable reactance).
parametric study Study based on numerical values of
system variables.
parametric take-off number Product of (landing wing
loading × 1.11) ×(MTOW ÷ [total installed thrust × C L2 ]).
paramotor Engine/propeller and seat unit [but no
landing gear] for attachment to hang glider or parafoil.
Hence, paramotoring.
paramp See parametric amplifier.
pararescue team Trained personnel who reach site of
incident by parachute and render aid.
parasheet Parachute in form of regular polygon with
rigging lines attached to apices; subdivided into gathered
* (periphery constrained by hem cord) and ungathered *.
parasite Aircraft, invariably aeroplane, which for
portion of flight relies on another for propulsion and
possibly also for lift. Can ride on back of parent, or be
attached elsewhere externally or internally, or be towed.
parasite drag Sum of all drag components from all nonlifting
parts of body, usually defined as total drag minus
induced drag. Not normally used (see profile drag).
parking orbit
parasitic element Resonant element of directional aerial
excited to produce directional pattern; eg reflector added
to Yagi aerial.
parasitic material RAM added [usually by adhesive] to
exterior skin to reduce RCS.
parasitic oscillation Generated by stray inductances and
capacitances and eliminated by parasitic stopper.
parasiting Technique of using parasite.
paraski Sport combining downhill ski with lifting
surface such as parachute, parafoil or hang glider; competitions
test landing precision.
parasol wing One from which rest of aircraft is
suspended by ties.; hence, parasol monoplane.
paravane 1 Hydrodynamic body towed (e.g., by helicopter)
on end of minesweeping cable.
2 Aerodynamic body towed on end of cable from
aircraft to keep line taut and steady, eg in mid-air
recovery.
para-visual director Attention-getting non-quantitative
flight instrument giving bold linear indication of excursions
in pitch or azimuth, generated by rotation of striped
‘barber pole’ display; usually mounted on flight-deck
coaming; indicator in GRDS is AMLCD (Smiths
Industries).
parawing Variation of basic Rogallo flexible wing
developed at NASA Langley for payload recovery and
marketed by Northrop; not current term in hang gliding.
PARC 1 Particle-Astronomy Research Council (UK).
2 Pacific Alaska range complex (USAF).
parcel Any small volume of gas, esp. of atmosphere.
Parcs Perimeter acquisition radar characterization
system.
PARD Pilotless Aircraft Research Division (NACA,
from 1946).
Pardop Passive ranging Doppler.
parent 1 Main aircraft in composite or carrier of
parasite.
2 Aircraft carrying one or more RPVs over which it
exercises control following release.
parent body Primary around which satellite orbits.
PARES Passive-radar ESM system.
parity 1 Symmetric property of wave function or other
phenomenon; value is 1 if function is unchanged by
inversion of its co-ordinate system.
2 Precise keying of two or more sets of data [eg EDP (1)
software, tapes, reconnaissance pictures or wire recordings]
so that they run to common time-base. System
parities are assigned individual tracks in such devices as
reconnaissance signal recorders.
park To establish synchronous satellite at its operating
position, where it is parked.
parked Aircraft, esp. commercial transport, not in
active use over extended period.
Parkerizing Anti-corrosion treatment in which metal
part is boiled in solution of phosphoric acid and
manganese dioxide and then dipped in oil.
Parker-Kalon, PK Patented family of self-tapping
screws for sheet.
parking brake That applied continuously after aircraft is
parked, to prevent subsequent rolling; also (US) called
park brake.
parking catch Fitted to normal handbrake (rarely, toe
brake) to convert to parking brake.
parking orbit Temporary spacecraft orbit for such
482