1 - NGA

MIL-HDBK-850
tepgmphk survey, bvtnm if may bemrns fmowr
aa a hydrogmphlc or topographic slgnaf.
trlangulstlon station-@CS) A point on the
Earth whose positii is datedrred by
triengutstion. AJm caflsd trtg point.
triangulation Syste*The main schema, or
M, d primaryststimam-d the awdii
atatbne. Therrdn mherrrs lsthefmmewrk d
he system and Is tii at aevemf pdrrts to
previouaty aatabfished kiangulatlon stations of
equal or higher order. sea afao survey *
defiiitien 1.
triangulation thoodolfta-Sae dlractlon
Inatrumant theodollta.
trlangatatbr tOwar—A sfrusture used 10
ebvate the fins of sight above krtervening
obstacles.. Usually consists of two independent
atruduras, one within the othw, the aenter
strtdure -S the Iheoddite and the outer
structure s-s the cbsarver and the signsl.
See alse Bllby steel towor.
trlangulallon-A method of surveying in Mich
the statiorra em points on the ground which are
lesdsd at ths van”w cd a tin or netvmrk cd
trisngfas. The anglea of the triangles are
maaaured h16tNmSMS~ and ills aides are
dw’tvsd by awnputstion from seJeded ddaa
tiih are termed base Ilnec, ths lengths of
wtr&h em cbfdned from direct maasuremsnts
on the ground. See also ●nalythml thtaapolnt
resection radial triangulation; arc
trlmrgulation; arms trhrn~ulatlon: baso
no~ dlraat radial tr’langulatlon; flratordsr
trlangulatlon; flare trlanoulatlon;
graphical rsdlal trlangulatlon; handtomplot
triangulation; Ieoaenter
trfangulatlon; mschartlcal-tamplet
trimrgulatlon; rmdlr-point trlangulatlon;
6hototrlsnaulatlon: radial trlangulatlon:
katollite tfiangulatlon; second+-rder
triangulation; aamlanalytlcal
trlangulatlon; ship-to+hore
trlangulatlon; slotted-templot
trlangulatlon; spider-tamplet
triangulation; third-ordor trlangulstlon;
trltataratlon.
trtaxtsl dUpaold-An ellipsoid hsvlng fhree
U~USl eses, the ahorfsst being its pelsr exis,
Mule the two bnger enes fie in the plsne of its
equator.
trlcamera photography-(JCS) Pholo-
267
gmphy obtained ky simultanaws exposure of
ttras cameras aysfemsticdy @Oaed in the air
vehicle et fixed twedappirrg angles mtstke to
each other m order to -v- s wide f~. see
abo fart camara photography.
trig cantro~ ffold control.
trfg douler-A detailed ramrd on the
trhguwon d M a-, g“w-rgthe moldiim
of the triarrgdsbrrStatbns.
trfg llst+JC.S) A Eat pdiahed by mrtsin Army
units which klctdea assentiel Mrrmsfii d
accurately krmted SLS’Veypoints. [A @rtkatbn
corrtainkrg all mmdabla poaitibnal dsta and
efavatime with the reapedke daeer@ibns of
t-mrizorrtel errdkr vertiml sontrol points. ususlty
srrsngsd ssmrdirrg to the location of the control
points within ths knits of msp Shasta of lsrgsscsle
series. ]
trig point-see triangulation atatlone
trigonometric levding-The determinstien
of diiersrrms et sIavstkms fmm observed
vertical arr@aS mmhhsd Wth lengths of lines. A
type of indirect bveJing.
trilatemtlon not—A network Of peints wheaa
p&tiens relative 10 one another are delarrninad
by measurement and adjusrrnam et the length
of the s.kfes d the trisngias formed by these
pdrrta.
trllateratiorr+l mathod of surveying wherein
the lengths et the triangle sides sre measured,
uauefty by elactronis methods, and the angles
are computed from the maaaured lengths. See
also triangulation.
trlllno=r ●urvaylng-Tha determinstbn of tha
podtii M a pdnt of cbm-vatbn by ~rfnu
the angks al that peint between Ilnes to thrse
pcints d knewn pesition. Ses afso rekmctlon.
trim msrks4_inea placed on origird mpy to
save as guides in cutting or trimming the
printed sheets to their presaribd size.
trim slza-(JCS) The size of a rnsp er chsrt
shaet wiwsn the excess paper eufaids the
margin has bsen trimmed oft after printing.
trlmetrogon camara—A triple cemare
assembfy with one vertical ard two freed-angle
ob~ques wtrese,imege!y ovartsppad the vertical
t