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phased array
phased array Physically fixed antenna (aerial) scanned
electronically, usually in both x and y (horizontal and
vertical) axes.
phase difference Measure of phase angle (1) from any
VOR radial related to that on bearing 000°.
phase discriminator Detector of phase modulation.
phase inverter Radio or other signal-processing stage
with unity gain whose output is reciprocal of input (not
synonymous with half-wave rectifier).
phase modulation Carrier phase angle (1) varies from
carrier angle by amount proportional to instantaneous
amplitude of modulating signal and at a rate proportional
to modulation frequency, PhM.
phase out, phaseout Progressive withdrawal from
production or active service.
phase shift Phase difference (not necessarily VOR);
change of phase angle (1).
phase shifter Circuits which steer the beam emitted by a
planar-array radar antenna.
phase velocity That of equiphase surface of travelling
plane wave along wave normal; also called wave
speed/velocity.
Phasst Programmable high-altitude single-soldier
transport.
PHB Pilot’s handbook (USGPO).
PHD Pilot’s horizontal display.
PHDD Projection head-down display.
PHE Penetrating high-altitude endurance.
PHEI Penetrator HE incendiary.
p-HEMT Pseudomorphic high-electron-mobility
transistor.
phenolic/epoxy Family of resins and adhesives much
used in composites derived from phenol (carbolic acid)
and characterized by oxygen bridges linking hydrocarbon
radicals.
phenolics Large family of synthetic polymers
(plastics/resins/adhesives) dating from 1907 and mainly
unmodified phenol-formaldehydes or (esp. in case of
adhesives) resorcinol-formaldehydes.
PH-15-7Mo Refractory stainless steel, primary
structure of B-70.
PHI 1 Position and homing indicator.
2 Pitot-head inoperative.
Phibuf Performance buffet-limit.
Phigs Prgrammer’s hierarchical international graphic
standard, or system.
Phillips entry Shape of leading edge of typical modern
wing [Horatio Phillips, patent, 1884].
Phills Portable hyperspectral imaging low-light
spectrometer.
Phinom Nominal bank angle.
PHLD Powered high-lift device.
PHM 1 Proportional hazards modelling.
2 Prognostic[s] and health monitoring, or management.
phon See noise; not used in modern work.
phonetic alphabet See Appendix 4.
phoney war Northern France, 3 September 1939 to 10
May 1940.
phonic wheel Sensor for tachometer, disc with precise
peripheral teeth which transmits signal at frequency
proportional to shaft speed.
phosphate esters Fire-resistant hydraulic fluids based on
esters of P(18) acids.
phosphor Substance which is luminescent; those in
radars/CRT/TV etc are commonly zinc sulphide/zinc and
selenide/copper compounds, but cadmium and rare earths
are common. Those for printing on opaque substrates are
unrelated.
phosphorescence Luminescence which continues more
than 10 –8 s after cutoff of excitation, usually being visible
to eye for days thereafter.
phosphorus P, three main forms, esp. white * soft nonmetal,
spontaneously flammable, MPt 44°C, density 1.8.
phot Non-Si unit of illuminance = lm/cm 2 = 10 4 lx.
photint Photographic intelligence.
photoactivated Activated by light.
photocathode Electrode for photoelectric emission.
photochemical Involving chemical change and emission/
absorption of radiation.
photochromic Having colour, transmittance or other
optical property changed by variation in incident light.
Also called photochromatic.
photochromy Colour photography.
photoconductive Having electrical resistance varied by
illumination.
photodiode Diode converting light into electricity; hence
* array yields signals which when processed analyse incident
light pattern.
photodrafting See photographic lofting.
photoelectric Involving light and electricity, usually by
absorbing photons and emitting electrons.
photoelectric cell Transducer converting EM radiation
in visible, IR or UV wavelengths into electricity; abb.
photocell.
photoelectron Electron ejected, eg from metal surface,
by impact of energetic (short wavelength) photon.
photoelectronics Involving electrons and photons (many
devices).
photoemissive Emitting electrons (ie electric current)
when illuminated.
photoflash Pyrotechnic cartridge producing brief but
intense illumination, esp. for lo-level night reconnaissance.
photogrammetry Making accurate measurements and
drawings, esp. surveying and mapmaking, by photographic
means.
photographic layout drawing Photographic lofting.
photographic lofting Lofting entirely with photographs.
photographic reconnaissance Photo reconnaissance.
photographic transmission density Log of opacity (base
10), thus perfectly transparent film has *** of zero, while
one transmitting only 10% has *** = 1.
photometer Instrument for measuring luminous intensity,
luminance or illuminance.
photometrical calibration Regular measurement of
output of all airfield lighting, especially on Cat II, III
runways.
photometry Science or technology of measuring luminous
flux, luminous intensity, luminance and illuminance.
photomultiplier Tube containing photocathode, several
intermediate electrodes (dynodes) and output electrode;
also called multiplier phototube.
photon Elementary parcel of EM energy emitted by
transition of single electron, with energy hν (h = Planck
constant, ν frequency) and momentum hν/c where c is
velocity of light.
photonic material
photonic material
Material designed to manipulate light,
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