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Ihe p0b6. AfsC ded ●pOX.
Vorfox of curve-sea point of
Int.rsoctlon.
Vettkal Obetructlon Data (VOfl)-Oata
fib containing dmte poaitim and hei@t
irderrrmt”bn d menrneda smf nstursl objads
exfartdii ebove the esrth’s a.urfeca et haiihte
thst Coufd mnstmin eipkanean dcnliwmisaife
ffiiht6 at levels Sslsbliihed by tin planners.
Vetlkd obcfr@kta Include msmnsde
ObStfUCf”~S such es radm towers, emekastaoka,
b~es, powwfinas, and other ebjada above
apeciried minimum efsvatbna. vOD is
~ by the Prcb6fMiiic Varfksd
obstruction Dsfe (Pvoo). see akm
Probabillstb Vottlcd ObstructIon Data.
vartkd sngk-t. An angfe In a vatticsl
plsne. 2. (surveying) One of the direstbns
whii form a vemid engle & uauaffy either the
dirsctbn of the verticsl (zenith), snd the angle in
termed the zorrfth dlatanccu or the fine of
intersection of the vertkal pfane in wtkh the
errgfm free with the pfsne of the trorizen, and Ihe
angle is termed the angfa of clevctlon or
●rgb of dopresslon, or simply the altltudo
(plus or minus, as the csse msy be). Ths vartiil
~W~ ~~ We di=ims, rrsilhsr of ti~h
has in the ptma of the horizon er caincicbs with
the vertii, is uauelfy dtsined from the
canbinatim of tvm verticsl sngfas se defined
above.
vartical ●gulatiOn-The pmcesa of
OMaining difhe.nces of efevation by means of
obearvaf vertical engfae, cotinad with Iangfha
ef fines. In geodatb wdc, trigermrnatric fevefing
is used wilh the same rneening.
v.rtlcd ●xla+lheodefiie: trsnsif) Tha fine
through the center d the msfrumsnf abouf
#ii the akdede rotates. FW an instrument in
cxm@sfe adjustment, this axia occupies a
verfioel pesifkm, passes through the oemer of
the fmrizorrtal tilde, and is perpendicufer to its
plane.
vortlcd bridging-see brldglng.
v.rtlcal ckcla-1. A great circle af the
celestial sphere, through tfrs zenflh and nadir.
Veti’ksl clmfss are perpendhhr to the hodzc.n.
2. A gradueted disk mounted on en instrument
in such a manner thst the plane of its gredusted
surfsce can be pfsced in e vetticsl plane. It is
primarily used for rn9ewring vertical angles in
MIL-HDBK-850
-.
z’76
warenomic and gacdetic wark.
vanicsl colllmafor-A tekcoopa so mounted
fJ’WtiCdtiti@-k~ tocmirckle
wifftffre vettisa d(wdktitidti~k).
The Vanicef COllinmaor Satv- as en @u
Plun-hhxl tmaybadaaimadf or-hpf=+tw
amsrkctt thOgrOUrKf dwOCfiY~r an
h’@Nti en n h~h tower w * cantering an
iluSN_ Oil 0 h@l klWSr di=t& OVOr a I_tUt’k
on ths gmurrd. Abe r4ed optfcd plummet.
verflcd cornparator+pendulum) A stand
das@tedforfhasqurtcfapnduJm, aixr
of known length, and fvm mismrnefar
~, so placed with rdaretv=a to one
another that the fengfh d the pandulun can be
measured.
vertkal control datum-Any feval surface
(as, far exan’pfa, mesn see Isvef) teken aa a
wrtssa d refere- fmm which to reckon
elevations. Alee called vwtlcaf datum;
vertical gnodetlc datum. Sea also d ●t urn
Ieval; refarence level; reference plane.
vorflcal control net-+ee eurvey net.
doflnltlon 2. ,
verflcal control pOlnt—See controf point;
control mtmtlon.
vertical eontrof-The rnessurements taken
by aurveymg methods for the detemrimsfbn of
ebvetbn onty with respect to an imsgfnery favef
wrfac9, uauaffy rnsm aee leveL Sea afse
survey nat dafinitiin 2.
vertical coordlnetea-llm vartical dwtanca
of a point above or babw a rsfarenoe datum.
Points mey bs piua or minus ~mg to
whether the point is ebeve or bebw the datum.
vertkal cutva-A psrabofii curve d to
connect gradea d dtierurd afepe, and used at
the vertex d e grade to avdd the sudden
chsngs M directim in peaa4ng from ma grsde to
the other. Tfis rnathed of grsda change fa
ususliy used when there is an afgebmis
dflerence of more thsn 0.2 percent in the two
opposing gredes.
verflcal datum—See vertical control
datum.
vertical deformation—in refetive orientetien,
the cumulst”we medel warpage affecting Ihe
vettksl detum from x-fill error and ~tift error.