00 UDAVID W. TAYLOR NiAVAL, SHIP CRESEARCH AND DEVFELOPMENT CENTER 0 tn
I Bethesda, Md. 20084
SEAICEEPT.NG EVALUATION OF THE JOINT ARMY/NAVY
BALLOON TRANS3PORT SYSTEM
by Ccz David M. Gertina
~~~~ ~~~APPROVED FOR PUBLIC UELEASE: ITIUIO NYIE
SHIP PERFORMACE DEPARUhEV
0
May 1976 SPD68O
MAJOR DTNSROC ORGANIZATIONAL COMPONENTS
COMMANDER
TECHNICAL DIRECTOR
OFCER-IN-CHARGE OFIE I-CAGCARDROCKANNAPOLIS
05 0
f SYST EMSIDEVELOPMENT
DEPARTMENT
r $HPPERORMACE IAVIATION ANDIP DERFOMANTCE SURFACE EFFECTS
DEATMN DEPARTMENT 1
. COMPUTATION...... T-CUE AND MATHEMATICS
DEPA RTMENT DEPARTMENT17
SHIPACOUTICSPROPULSION ANDSHIPACOTINS AUXILIARYV SYSTEMS
DEPAR MENTDEPARTMENT 27
MATEIALSCENTRALMATEIAL N. I NSTRUMENTATION
DEPARTMENT DE.PARTMENT2B /_____
.. zz
AA. N1
ql4
UNCLASSIFISDV ~~SECURITYr CLASSIF1CATION OF THIS PACE gfnion bale £tlsmo__________________
KPIN XLUATION OF THS JOXWARHP(/AVY
TWAISPORTA)S~
1.PIFWI ORGANIZATION NAME AND ADDRESS 0 a PROGRMLEMtN.RJ.T AtSh p r orance Department AIbWRK UNIT NUMSICI$David W. Taylor Nava) Ship R&D CenterBieathesda, Marylandl 20084 Ui
IL. CONTROL.LING OFFICE NAME AND ADDRE.SSaMobile Support System Group my0§David W. Taylor Naval Ship R&D Centert3 M9 OPAEAnnapolis, Maryland 2
14. MONITOItNG AGENCY NAME ADDRESS(## diUqt Em,, Ottt~ti1c.) It, SECURITY CL~ASS, (of this f00)
Unclassified
* APPROVED FOR PUBLIC RELASE. DISTRIBUJTION UNLIMITZED
Is.$UPEIMiNYANY NOYIK$
} Balloon, Traueport, Seakeeplzig, Vessel Kotiouo, Container Of floading
10. A"YRACT (CflhIto~ 44 rdAV**0 old#. It .,."W~ 40 I4.$UJ& br Wftk .Imv)
-Iiiurnsthe fivalukktion, of the joint Aray/tNavy Balloon Trawiport Systemconducted off of Green Beach, Ft.* Story, WVginia, the David W. Taylor N~avalShip Reear, h and Developzent Centor (DTNSRW)C vas tasked to mesure shipmotions on somie of the vessels used in the operation. The vessels instrwmonteby WNSWC were the Army's BM~ "LT. COYL. 3M-I V. D. PAGE," the LST 1180 '"tJSSK4NLTOWV~,g and two Navy W.AUa of the 1610 series (1658 snA 1659). Two prlaci-pal con~lguratione to remove Hilvan containers from thu vessels vere
WO W 43 es"Io'IOV~~OO~ya
ItCJMT~LAUziFCATIOS OF II PAGO ga9kV.1
UNCLASS!IEUD10-UITY CLASSIFICAMIN Of YI4S PAGE(Wha.e Date Mo.tored)
1nveatigated. The f irst was a ship to shore maneuver for which DTKSflDCinatrumented the BDL and the LCU 1659. The second was a ship to lightaroperation for which DTNSRDC recorded ship motion* on the LST 1180 Ad theLCUO 1658 and 1659. Throughout the operations, the motions of the vessel$Investigated were, In generalt rather small with the largest motionsoccurring aboard the LCUs when they vera fendered off of the larger DDLand LST with Yokohama pneumatic fenders.* The vessel motions were not thelimiting factor in the operation of the balloon transfer system. ObservatimIndicated that the ability to get the vessels into th.proper position andweather operational limi~ts of the balloon were of greater significance in
........... the successful transfer of Hilvan containers from the vessels.
~L
SaCURi~v CtLAW1P1C4%1104 Op y"Ih PaO((f. ii "a #A###"
A.I
TABLE OF CONTENTS
Page
ADMINISTRATIVE INqPOEMAIUN o.*.f t0f t~'f t~".f t
INTRODUCTION e ftf t fft'f t ',1
--7SSEL PARTICULARSo INSTRMIhFMATION AND DATA ANALYSIS . . ... . . . 2
BDL "LT. COL. JOHN U. D.PAGE" * f tff tfttfttfttft2
LST 1180 "USS MANITOWOC" .t . . t. ft ft . f .f . .f ft .ft . 3
LCU 1658 AND 1659 . ft . t . ft . . . . . ft ft ... . . . . 3
DATA REDUCTION TECHNIQUE ftf tf tf tf t-f tf tf t00f t 4
TRIAL CONFIGURATIONS . ft .t .t .tf tf tf tf tf f tf t*f tf 5
RESULTS AND DISCUSSION .ttff ft . t . t ft . t ft . t ft . t ft.*f f. 6
CONCLUDING REM4ARKS .tttfff ft ft.f*f tf tf tf tf tf 7'
LIST OF TABLES
Table 1 - Single Amiplitude Siguificant Voluea for the SDLand LOU 1659 iv., the Ship to Shore and Ship toLighter Corfigratio .f..f 4 . . . . . 8
Table 2 - Single Amplittudt Maximum Values for tiie BDLand LOU 1659 in the Ship to SIbove and Ship toLighter Configurations f0 tf f tf tff 9
Table 3 - Single Amplitude Signiificant values for theLST 1180 and 1ACUa 1658 aud 1659 in the Shipto Ligher oafigu ratto.. I . .. . . .t. . .. . .... 10
FTable 4 - Single Amplitude Haxiium Values for the LST 1180and LCUs 1658 aud 1659 in the Ship to Lighter
Configuration . . f t . . . . . . tf tf t tf t1
.ZL
Figue 1-Recosrted fo PR r Baloo 3,I 4 5 of th Balo Transporgeiue2 Shiptom Shluoan Sh1t5ihe Cniuain
Figure 4 Wave Height Spectra versus Wave Frequenicy asRecorded for Runs 2, 3, 4, 5 of the Balloon TransportSystem Evaluation . . . . . . . . . . . . . . . . . . . . . 5
Figure 6 Wave Height Spectra versus Wave Frequency asRecorded for Rune 6, 1, 8,t 9 of the BalloonrsptSyasotm em Evaluation .. . ........ 16
Figure 6 - Wave Height Spectra versus Wave Frequency an
Rec~orded for Runs 14, 15 of the Waloon TransportSyatem Evaluation~ , . . * .. * .. 18
iv
ABSTRACT
During the evaluation of the joint Army/Navy Balloon Transport System
conducted off of Green Beach, Vt. Story, Virginia, the David W. Taylor Naval
Ship Research and Development Center (DTNSRDC) was tasked to measure ship
motions on some of the vessels used in the operation. The vessels instrumented
by DTNSEDC were the Armys a DL 1LTQ COL. JOHN~ U. D. PAGE." the LST 1180 "USS
MANITOWOC," and two Navy LOUB of the 1610 series (1658 and 1659). Two princi-
pal configurations to remove Milvani contcine~s from-the vessels were investi-
gated. The first was a ship to Shore maneuver for which DTNSRDC instrumented
the BDL and the LCU 1659. The second was a ship to lighter operation for which
___ IDTNSRDC recorded ship motions on the LST 1180 and the LCUs 1658 and 1659.
Throughout the operatiLons, the motions of the vessels investigated were, in
-~general, rather small with the largest motions occurring aboard the LGUs when
they were fendered off of the larger BDL and LAST with Yokohama pneumtic
fenders. The vessel motions were not the limiting factor in the operation of
the balloon transfer system. Observations indicated that the ability to get
the vessels into the proper position and weather operational limits of the
balloon were of greater significauce in the successful transfer of HilvanW containere from the vessels,
ADMINISTRACIft INOMAION
This vork ws authorized by the N~aval Vcilities Xugineerin& Commaud
Work Request Wfl 09090 and identit-ed as Work VUit 1-1175-128.
ENV~ODc~O~
Invtatigations of the joint Army/N~avy Balloon Transport Systez were
conducted off ot Green Lucah, Vt, Story, Virginia, during the apriuR of 1076.
Ship to 3hOte and from ship to lighter by means of a helium filled ballooa.
n. l AThe primary balloon syc~tem, see Pigure 1, consists of a 500,000 cubic
foot helium filled balloon, two yarders (diesel powered level wind winches) and
a third winch, used in a manner similar to the yarders, for positioning the
balloon. The yarders are used to control the elevation and lateral positioning
0f the balloon in a plame bounded by the distance between the yarders and the
length of the cable on the yarder reels. The cable from the third winch is
attached to a block through which passes a cable from one of the yarders and,
with proper positioning of the !'Flying Dutchmaus" enables the balloon to be
moved transversely out of this plane.
Duiring the operations one or both yarders were aboard the LCUs, and the
winch of a warping tug, i.e., "ligDutchman," was used as the third point
of control in the positioning of the balloon, Ship motion measurements were
recorded by the Center on the LCUs which carried the yarders and aboard the
container carrying vessels, the BDL and LST.* Seakeeping data were collected
when the MIilvan containers were being on or off loaded from the vessels, The
results of this seakeepiog inormation are presented in graphical and tabular
form to aid in the overall evaluation of the feasibility of the balloon trans-
port system.
VE~SSEL PARTICUL=IN lSTRMWbTATIO4 AN~D DATA ANALYSIS
ML"LT. COL. JOOI U. D. PAGE"
The Army M is a 304.2..foot (92.72 toetra) landiug craft with a 65-foot
(19.81 %Letre) beam, 7.5-foot (2,29 metre) draft, and a disoplAcement of 2345
long tous (2383 tonnes). In the balloon transport system evaluation, tht BDL
was principally used as a container carrying vessal from which Milvau cou-
tatters were removed in the ship to short operation. Thriug these operations
the BflL was equipped with a Mark IV s table platform to measure the ship~ '
motious. The Mark TV stable platf~orm measures ship pitch, roll, and vith
j three stabilized axis accelerometers yields the vertical, transverse, a-ad
Niaval Ship Engineering Center, Norfolk. was responsible for twtion maasure-tumt abardthewarping tug ad Owe Iaveride-t buoy.
2
4 longitudinal accelerations at the point of installation, The installation
location of the ark IV aboard the UDL was 1.5 feet (.46 metres) to port of
centerline at amidships and two levels below the main deck, Thus acceler-ations measured at this point (near the ship's center of gravity) .;ould be
converted to displacements representing heavet sway and surge.
LST 1180 "USS MANITOWOC"
The LST 1180 is of the "Newport class" and has a full load displacement
of 8342 long tons (8476 tonnes), Its length overall is 522.3 feet (159.20
metres) with a beam of 69.5 feet (21.18 metres) and a draft of 15 feet (4.57
-" metres). The LST 1180 was used in the ship to lighter operation with the
LCU 1658 tied alongside. A MNSRDC strap down motion package was used aboard
j i!!:i ithe LOU 1658 with pwer for the cloctronic transducers comin from the enuip-
ment used aboard the LST. This power requirement limited the positioning of
the electronic equipment aboard the LST to an area where a cable run to the
LCU 1658 could be made. An area for the Mark IV stable platform location was
selected at Frame 235, 8.5 feet (2.59 metres).below the main deck and 12 feet
(3.66 metres) starboard of centerline in the PASSAGE AN) CONFLAGRAtION STATIONNo, 2 (2-235-11. This is a s"all compartmeut one level below the main deck,aft of the tank turntable and helicopter landing pad. The use of this location
did not permit heave, surge and sway measuremets o- the ship's center of
gravity, However; it did allow meAsuremente of the vertical, transverse &ad
lougitudinal accelerations of a point near the llflvau contaiuer off and on
lotding operations, and enabled the necessary cable run fot the LOU 1658.
LCU 1658 ND1659
S .. The LCU 1658 and 1659 are of the 1610 series with a length overall of
134.9 feet (41.12 metres), a bea of 29 feet (8.84 metres) aud a draft of
6.1 feet (1.86 metres), The LWl of the 1610 series have a light displacement
of 200 log tons (203.2 tonnes) and a full load displacemeat of 375 long tons
(381.0 tonnes).
Tlhe LCU 1659 wtm instrumented with a Humphrey stable platform which
is equipped with a vertically stabilited directiona gyroscope for pitch and
roll measurements and three axis accelerometers. During the first stages
3
of the operation these aceelarometerf. Ratiled and were replaced by a Donner
double integrating accelerometer for the heave displacement signal and two
hard mounted accelerometers for surge and sway acceleration signals. The
surge and away accelerometers wcre part of the DTNSRDC strap down package
which was later moved to the LCU 1658 for the ship to lighter operations.
The electronic transducers were positioned near the center of gravity of the
LCT 1659 6.8 feet (2.07 metres) below the main deck. 11 feet (3.35 metres)
aft of bulkhead 40 and on the centerline.
The LCU 1658 was instrumented with the DTN4SRDC strap down motion package
which consists of a Honeywell gyroscope to measure pitch and roll and three
hard mounted Donner accelerometers to measure vertical, transverse, and longi-
tudinal accelerations. Due to a limited length of transducer cable, the
location of the DTNSIU3C strap down package was dependent upon the location
along the length of the LST at which the LCU was tied. For Russ 11 through
14 the LCU 1658 was positioned A.loug the -port side of the LST with its Widshipa
centered on rame 184 of the LST iund the location of the strap down packageaboard the LCU was on the ceaterline of the main deck at rame 1$. For Rua 15the LCU 1658 was positioued along the starboard aide of the TOT again with
its midahIps centered about Frame 184 and thta strap dowan wotiou package was
relocAted on the ceaterlina of the maiu deck at Frame 55.
Throughout the duration of the operations the sea state was mea ured by
Mea of a Dfitawell 1Vamorider buoy provided by UAVSE, N~orfolk.I 13A.IUA REBUCT ION TEMWQQUEThe data signals were recorded on vioual direct writing oacillograph
uWits ad analog tape recordera during the luvestigatious. The ansag tapes
ver(- later digitized aud analyeced at the Center on an luterdata computer. The
calibrations were entered into the computer as tagineering units per volto
Sa a the data were digitized, prelimiuary analyses were perfomad to givethe mean ad root =ean square values for each chael.
Two comp~uter psasts were made on the data. During the first piase the
mean valua of the signal was computed along with rAxlmum and minimum values
from tlhe digitized tima domain data. During the second pass the teAu is
4
V subtracted on a point by point basis from the data, while a EAST FOURIER
TRANSFORM spectral analysis is performed on the data to yield the signifi-
cant values.
TRIAL CONIGURATIONS
In the evaluation of the balloon transport system there were two princi-
pal operational configurations, These were the ship to shore and the ship to
s!.lighter configurations. The ship to shore operation involved three vessels
as indicated in the upper half of )igure 2, i.e,, the BDL, the LCV 1659 andthe Warping Tug No. 34. In this operational mode, the B3Db was moored and
umsed as a container carryirg vessel. The LCU 1659 was tied to the starboard
side of the BDL and equipped with a yarder to serve as one point of control
for the balloon. The second yarder was on the beach and the warping tug'- ;(equipped with winch and block) served as a "Plying Dutchman." During the
ship to shore operations the LOU 1659 was tied to the starboard side of the7.1 BDL with its bow directed toward the WL'a stern. The LOU was positioued
forward of the lL'a midships aud feudered off of the HDL with two Yokohoa
fenderu. As seen in the upper half of Figure 2, tht principal direction of
the s.ell compouent of wave height during these operatious was off of the
BDL's starboard bow sad the L U's port stern. As iudcated, the apparent
j direction of the swell varied relative to vessels. This was due to the
shifting of mooring lines and chan g sn he vessels' position. The relative
positioning of the vessels involved in the operation is critical to the
proper maneuverabia.y of the balloon in trying to remove Kilvan containers.
In the Ship to lighter operations, both yarders awere aboard LCUs and
all three points of control were attached directly to the balloon tethering
liae as indicatel in the lower half of Figure 2 and in Figure 3. The first
attempt in the ship to lighter operation involved the 13DL, LOus 1656 and
1659 and the uarping tug. During this briaf attempt to move containers from
ship to lighter, the tooring of the BDL shifted and no containers were off
*loaded (Run No. 10). The remaining runs were conducted using the LST 1180,
LCUs 1658 and 1659, and the warping tug. As iudicated in Figure 3, the
* relative mooring configuration between the vessels changed; this was
principally the result of the change in current direction and an attempt to A
keep the LCU 1658 on the lee side of the LST. As seen for Runs 11 through 14,
the LCU was fendered off the port side of the LST with its bow directed toward
the LST stern. The midship position of the LCU 1658 was located about Frame
184 of the LST with the LCU 1659 seaward of the LST and the warping tug off
the LST's stern. The vessel configuration for Run lF ras similar to that for.the other ship to -ighter operations with the exceptLin of changing sides of
. -the LST and the wind driven waves being 180 degrees out from the swell.
RESULTS AND DISCUSSION
Presented in Table 1 are the single amplitude significant values for the
ship motion data recorded aboard the BDL ard LCU 1659 in the ship to shore
and ship to lighter configurations. In adeition to the single amplitude signifi-
cant values for each data channel. the d~ste, run number, tima of run and aigi-
.-icaut wave height, ( )1/3, are given. From this information the wavo spectra
measured during each run can be selected from Vigures 4 through 6. In those
instances where data were unobtainable due to tranaducer failure, electronic
malfuaction, technical difficultiei in oeneval. ete, the *ord "out" i used.
The (0) for Ruu No. 5 is to indicate that the data for the LOU 1659 was not
recorded simultaneously with that .f the bML. The time of day for Rad 5 on
the W vas from 1340 to 1405. The sea dtate condition during which fic +'
the vesel's data were being recorded for Run 5 was the 040*4 however, the
LCU 1659 was being repoaitioned (moved approxmatuely 30 feet farther forward
along the length of tha 9DL) while its motions were recorded.
In a similar format, Table 2 proaenta the single amplitude maximum values
recorded for the BDL and L U 1659. The umximum values for the displacement
siguals obtaiaed from double integration of acceleration signals are unobtain-
able, since the maximum values are obtalued from the time domain auglysis
and for these channels this would be in terms of g's, not fett.
Tablet 3 and 4 present the single amplitude significant and maxium values
recorded aboard the LST 1180 and LCJs 1658 and 1659 during the ship to lighter
." operations. The format used in presenting the data is the 6aze as for Tables
1. 1 6
1 and 2. The wave height spetra recorded for, each of. the runs are given inFigures 6 and 7.
A. indicated in Figures 4 through 7, the significant wave heights measured
were of the same magnitude for moet oi the runs in both operating conditions.
The spectra presented are point spectra and thus reflect the total wave energy A
regardless of direction. The swell component that existed off of Green Beach
was generally directed straight onto the shore and was the principal source
S-,of wave energy, as indicated in the various spectra as the modal period (period
of uaxmum enegy), with the windkgenerated waves having no noticaably differ-
, ient direction except as previously indicated tor Run No. 15. The direction of jthe principal swell component, as indicated in Figures 2 and 3, was derived
visually, and in many instances was difficult to determine due to the small
.F wave height and superimposed wind waves.
CONCLUDING REMARKS'I
As seen from the tables of single amplitude significant and the maximum
values presented, the motions of the vessels were, in general, relatively
small and did not inhibit the balloon transport operations. The largest motions
recorded were for roll on board the LCUs wheu they were fendered off the larger
vessels with Yokohama fenders. The motions of the LCUs were aggravated by the
stretch of the nylon lines and the resilience of the Yokohama pneumatic fenders.
Observations of the overall operation indicated that the ability to get
the vessels into the proper position and weather operational limita of the
* balloon are of greater significance in the su,'cessful transfer of Milvan con-
tainers than are the absolute motions of the vesse.ls involved. ..
7
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"FLYING DUTCHMAN"
SHIP TO SHORE CONFIGURATION
~ I RUNS 2, 3. 4. 5, 6, 7, 8, 9
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LCU 1659
PRI NCIPAL DIRECTION OFSELCOz6'ONEW~
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['V RUNS 11, 12, 13, 14'INSTituKEnE VESSELSN
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Figure 4 Idave H(eight Spctr a vros 'Wave Frequenicy as Recorded forRuns 2, 3, 4, 5 of the Ulloou Tiwanspor.t System Evaluati.on
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16
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Figure 6 -Wave Height Spectra versus Wave Frequency .as RecoddfoRtune 10$ 11, 12, 13 of thie Balloon Transport System~ Evdatioui
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Viue7 -Wave HLI>it Spectra versus Wave 'Frquency as Recorded for
Ruue bns 14, 15 of the Ballooni Transport Systez Evaluatio
Sz1