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R D-Ri68 657 FORACS (FLEET OPERATIONAL READINESS ACCURACY CHECK / SITE) TARGET SSRNM (SU..(U) NAVAL FACILITIES IENGINEERING CO!MANDV MASHINGTON DC CHESAPEAKE. I UNCLASSFE L MENDL W ET AL N 4 F/G 7/1i U *uuurnuuuuui 'MENlflOMOflEEf ks2.2 L36 1111111L IILA~l 'liii-JillI M B I' ''N eft Novmbe 18 F (0 PROJAECTE DI CUMISAIONRPR NAVALFRAC TAITIS NIERGET4AN W SH RARYINSTALLACT2037 00 NAA ~~FACILTIE NIEMNG AW ~~~~ATMN A~a~g 4 9 aalcrlo C-2 86 6 12 001 DTIC 4 S ELECTE JUN 12 8 ~ PROJECT DOCUMENTATION REPORT FORACS TARGET SSRNM ARRAY INSTALLATION AUTEC/St. Croix November 1984 FPO-1-84(31) Prepared by: Lawrence Mendlow -. Bruce Schuckman Sandra Vickstrom Approved: D. A. Raecke, Director E. B. n cer,.Tech~nical Director construction Division Ocean Engineering and Construction Project Office Ii.c \ 1tpub Tel DiMti.i~ _____ Unclassified SECURITY CLASSIFICATION OF THIS PAGE ...... REPORT DOCUMENTATION PAGE la. REPORT SECURITY CLASSIFICATION lb. RESTRICTIVE MARKINGS Unclassified 2a. SECURITY CLASSIFICATION AUTHORITY 3. DISTRIBUTION AVAILABILITY OF RE Approved for public release; distribution is unlimited * 2b. DECLASSIFICATION/DOWNGRADING SCHEDULE 4. PERFORMING ORGANIZATION REPORT NUMBER 5. MONITORING ORGANIZATION REPORT "9' FPO-i-84(31) 6a. NAME OF PERFORM. ORG. 6b. OFFICE SYM 7a. NAME OF MONITORING ORGANIZATIO Ocean Engineering & Construction Project Office CHE SNAVFACENGCOM 6c. ADDRESS (City. State, and Zip Code) 7b. ADDRESS (City, State, and Zip BLDG. 212, Washington Navy Yard Washington, D.C. 20374-2121 8a. NAME OF FUNDING ORG. 8b. OFFICE SYM 9. PROCUREMENT INSTRUMENT INDENT 8c. ADDRESS (City. State & Zip) 10. SOURCE OF FUNDING NUMBERS PROGRAM PROJECT TASK WORK Ulf ELEMENT # * * ACCESS ' 11. TITLE (Including Security Classification) FORACS Target SSRNM Array Installation AUTEC/St. Croix: Project Documentatil Report 12. PERSONAL AUTHOR(S) Lawrence Mendlow. Bruce Schuckman & Sandra Vickstrom 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REP. (YYMMDD) 15. PAE FROM TO 84-11 18 16. SUPPLEMENTARY NOTATION 17. COSATI CODES 18. SUBJECT TERMS (Continue on reverse if ne( FIELD GROUP SUB-GROUP FORACS. Arrays. Atlantic Undersea Test ar ____-__ __Evaluation Center. St. Croix 19. ABSTRACT (Continue on reverse if necessary & identify by block number) NOSC Code 6362 tasked CHESDIV FPO-1 to install two FORACS Targets at AUTEC. Andros Island, Bahamas and one FORACS Target and c.e SSRNM Array at the Underwater Tracking Range. St. Croix. USVI. 20. DISTRIBUTION/AVAILABILITY OF ABSTRACT 21. ABSTRACT SECURITY CLASSIFICATI SAME AS RPT. 22a. NAME OF RESPONSIBLE INDIVIDUAL 22b. TELEPHONE 22c. OFFICE SYMB( Jacqueline B. Riley 202-433-3881 DD FORM 1473, 84MAR SECURITY CLASSIFICATION OF THIS PA ++i ,.+ . . . J . - . + Jr - . . *** *,. -C ' , . .... -. . " CTABLE OF CONTENTS * List of Tables iii List of Figures List of Acronyms iv -' 1.0 Management Summary 1 1.1 Background I 1.2 System Description - FORACS 1 1.3 System Description - SSRNM 3 1.4 Construction Site - AUTEC 3 1.5 Construction Site - St. Croix 3 1.6 Construction Planning Summary 5 1.7 Construction Operations Summary 5 2.0 Location Details 7 2.1 Geographical Data, Site Plan, and System Element Locations 7 3.0 Installation Details 7 3.1 Installation Details/Comparison with Specifications 7 4.0 Recommendations for Future SSRNM Installations 11 Accesion For NTIS CRA&I OTIC TAB 03 Unannounced 1 justification ... .. ...... By ...... . ...... Dist. ibuton Availability Codes Avail and I r Dist Special [A -, LIST OF TABLES 2.1 AUTEC Installed Locations 8 - 2.2 St. Croix Installed Locations 10 LIST OF FIGURES 1.1 FORACS Target 2 1.2 SSRNM Array 4 . 2.1 AUTEC Installations 9 2.2 St. Croix Installations 11 3.1 SSRNM Termination Device 13 • , ,WO 1 i '-p LIST OF ACRONYMS d CHESDIV Chesapeake Division, Naval Facilities ,- - Engineering Command. " NOSC Naval Ocean Systems Center. UCT-1 Underwater Construction Team One. APL Applied Physics Laboratory, University of Washington. . AUTEC Atlantic Underwater Test and Evaluation Center. AFWTF Atlantic Fleet Weapons Training Facility. UTR St. Croix Underwater Tracking Range. DTNSRDC David W. Taylor Naval Ship Research and Development Center. SUPSALV Supervisor of Salvage, Naval Sea Systems Command. BIW Boston Insulated Wire Company. FORACS Fleet Operational Readiness Accuracy . J-. Check Site. SSRNM Surface Ship Radiated Noise Measurement. V 'Il . . ' , .. i 2-. .qp- - - - - - - - - - - - 1.0 MANAGEMENT SUMMARY I 1.1 Background NOSC Code 6362 tasked CHESDIV FPO-1 to install two FORACS -. Targets at AUTEC, Andros Island, Bahamas and one FORACS Target and one SSRNM Array at the Underwater Tracking Range, St. Croix, USVI. The organizations that participated in the project were: 1) NOSC - Funding, SSRNM Equipment and ET's. S.-2) CHESDIV - Installation Planning, Installation Coordination, "' SEACON. 3) UCT-1 - Deckforce, Installation Planning. .4) APL - FORACS Equipment and Engineers, FORACS Targets Positions. 5) AUTEC - On-site Logistics. 6) AFWTF - On-site Logistics. NOSC funded the project through the following documents: N66001 83WR 00412 $30,000.00 23 JUN 1983 , N66001 83RC 00097 $100,000.00 10 AUG 1983 N66001 84WR 00086 $10,000.00 4 NOV 1983 N66001 84WR 00214 $137,000.00 19 JAN 1984 , . N66001 84RC 00053 $78,000.00 8 FEB 1984 N66001 84WR 00391 $45,000.00 23 APR 1984 N66001 84WR 00491(Amend 1) $4.000.00 22 MAY 1984 N66001 84RC 00094 $32,000.00 22 MAY 1984 1.2 System Description - FORACS FORACS ranges consist of a series of radar and acoustic targets used to check the accuracy of a ship's sensors. CHESDIV was tasked to install several acoustic targets (a deep and shallow water target at AUTEC and a deep water target at St.Croix with a backup to be installed as a shallow water target at St.Croix if time permitted). " See Figure 1.1 for a typical FORACS acoustic target. Each target is separately cabled back to shore (with Simplex .057/.180 Quad Cable) and into a control panel located in the control room of the appropriate facility. CHESDIV efforts consisted - iof bringing the cable to the on-shore termination boxes. The connections to the termination boxes and the cabling and connections between the boxes and the control panel were carried out by the facility and APL. i"A -w w-- .-- wv-w-L-wt--wv'rr"r ~ r~"F1r r- W Y-' r.C W-? - - - ..~ "., N. V. S. / - ri N. N. FURACS Target Figure 1.1 -p V N. is'., 2 ..-.. ~* ~ .-.- c*~.- - - - - - - . - . . - . . . . - - - - --.--. . .-.- '-- '--. - ~ - .- The targets were designed and built by APL. The target locations were selected by APL after consultation with the respective facilities. The position was not considered critical so there was no specification of accuracy in the X-Y plane. However, depth was considered important and specifications for depth were given; for the shallow targets the depth was permitted to vary from the selected depth to 10 ft deeper than the selected depth. For the deep targets the depth was to be between 1200 and t- 1300 feet. However this was permitted to be varied on site with the consent of the APL engineer on board. 1.3 System Description - SSRNM The SSRNM system is a vertical acoustic array designed to analyze the acoustic signature of a surface ship. The SSRNM array consists of a subsurface float, a Kevlar strength member, electrical cables and four hydrophones. The array was also designed to have a powered pinger on it for 3-D location on the range. The array is held in position by a concrete clump (17.000 lbs in air, 9,600 lbs S in water). A specially designed cable connects the array to shore, with transformers in a junction chamber at the base of the array to insure proper signal strength/impedance. On shore is an electronics van where all the signal processing occurs. See Figure 1.2 for SSRNM Array. The array was designed and built by NOSC in conjunction with 0 DTNSRDC. The location was provided by NOSC and the UTR. Once again vertical control was considered more important than horizontal control. Horizontally, a several hundred foot error was considered r acceptable, but vertically, the top of the buoy had to be between a depth of 100 ft and 120 ft, based on the draft of large tankers and diver limitations. 1.4 Construction Site - AUTEC AUTEC is located on Andros Island, Bahamas. It consists of an acoustic range, a weapon range and a FORACS range with all the support facilities to maintain the base, the ranges and all the equipment that the ranges use. The cable landing site was inside a --. '- [ cut in the reef permitting SEACON to approach no closer than 1 mile from shore and necessitated use of an AUTEC LCM-6 to pull the cable to shore. An existing cable trench was used to route the cable from the beach to the Command and Control building. - -1.5 Construction Site - St. Croix The St.Croix UTR under the cognizance of AFWTF, Roosevelt Roads, PR is located at Sprat Hall, 1 mile north of Frederiksted, ST.Croix, USVI. 3 IviELDFD ~bOLTED UCY NET eUOYANCY 4170 LBS HYDROPHONE -2 r K_____2631 FT. Ii HYDROPHONE =3 2b1 3 FT. ~7 HYDROPHONE UL4 IEl "'AP CE ;EXTRA 300 FT. OF 7 K__ SECUR7D 1-0 BRACK<ET __________________- C9LMP PLP STOPPER 'STRAIN RELIER 'D02 L BS. WATP -p-p SSRNM ARRAY Figure 1.2 4 m v The facility overlooks the beach landing site on a steep 30 ft high bluff. The shore drops off fairly quickly, permitting SEACON to approach within 1200 ft of the shore. 1.6 Construction Planning Summary S: 23 Jun 83 Original tasking for FORACS/SSRNM Installation. 17 Nov 83 Dates of Installation and use of SEACON finalized. 19 Jan 84 Op order 2-84 promulgated. 20 Mar 84 Project Execution Plan - FPO-1-84(l) promulgated. 20 May 84 Addendum to PEP promulgated. 22 May 84 Op order 3-84 promulgated. 1.7 Construction Operations Summary 13-18 Feb 1984 SEACON towed from Norfolk, VA to Fort Lauderdale. FL. 19-30 Mar SEACON and project mobilization at Fort Lauderdale. FL. The effort included the assembly of the FORACS structures. the winding of the electrical cables and the Kevlar rope onto Pengo reels. and loading the SSRNM cable in SEACON's cable tank. 31 Mar - 1 Apr SEACON transited to AUTEC. 2 Apr CHESDIV personnel setup Miniranger shore stations. UCT-1 and AUTEC personnel set up the beach site for hauling the cable ashore. 3-4 Apr Installed deep water FORACS Target. 5-6 Apr Installed shallow water FORACS Target. 7 Apr UCT-1 and CHESDIV personnel pulled the near shore portion of the cables into position and demobilized the shore sites. SEACON departed AUTEC. 8-13 Apr The USS PAPAGO. ATF 160, towed SEACON to NAVSTA Roosevelt Roads. PR. 5 13-14 Apr Picked up the SSRNM clump and the FORACS cable for St.Croix Operations at NAVSTA Roosevelt Roads. Wound the FORACS cable on Pengo reel. 15 Apr SEACON transited to St.Croix. 16 Apr UCT-1 and CHESDIV personnel set up the shore site. 17 Apr Plumbed the SSRNM site and cut the SSRNM Kevlar strength member to match the depth at the installation site. -NOSC personnel installed a new socket on the Kevlar strength member. 18 Apr Installed deep & shallow FORACS Targets. 19 Apr Equipment failure caused loss of SSRNM clump/shore cable/junction chambers. 29 Apr With SUPSALV personnel using Deep Drone aboard USNS MOHAWK, T-ATF 170, the clump was recovered aboard SEACON. 30 Apr Recovered the shore cable into the SEACON's cable tank. I May UCT-1 and CHESDIV personnel broke down the shore site. SEACON transited to NAVSTA Roosevelt Roads. 14-18 May BIW reterminated the SSRNM cable on board SEACON. 23-25 May SEACON mobilized at NAVSTA Roosevelt SRoads. 25-26 May SEACON transited to St.Croix. 26 May Set up the shore site. 27-28 May Installed the SSRNM array. 28 Ma, Demobilized the shore site. 28-29 May SEACON transited to NAVSTA Roosevelt Roads, PR. 30 May Demobilized SEACON 6 der."- -'' 'S T 2.0 LOCATION DETAILS 2.1 Geographical Data, Site Plan & System Element Locations AUTEC is located at Andros Island Bahamas. The FORACS Range uses a local grid with the North Tower as the origin and the Y axis *:. at an azimuth of 305.90. CHESDIV chose to use a grid system based on true north and selected on old AUTEC construction grid. In this system the location of the North Tower is (11430 X. 47625 Y). To convert from the FORACS grid to this grid system use the following formulas: Xcg = Xf Cos(305.9) - Yf Sin(305.9) + 11430 Ycg = Xf Sin(305.9) + Yf Cos(305.9) + 47625 To convert from the construction grid to the FORACS grid use the following formulas: Xf = (Xcg - 11430) Cos(305.9) + (Ycg - 47625) Sin(305.9) Yf = (Xcg - 11430) Sin(305.9) + (Ycg - 47625) Cos(305.9) The conversion from latitude/longitude to FORACS grid is done by the range. The North Tower and the Instrument Tower were used as miniranger transponder stations. The location of the miniranger stations and installed targets are shown in Table 2.1 and Figure 2.1. The St.Croix Underwater Tracking Range is located on the west side of St.Croix, north of Frederiksted. The range uses a local grid based on a rotation and translation of UTM coordinates. This was the system used for this project. Conversion between latitude/longitude and the grid system is accomplished by the range. Sprat Hall and the Coast Guard Light at the foot of IL Frederiksted Pier were used as miniranger shore transponder sites. The locations of the miniranger sites, the FORACS targets and the SSRNM array system are shown in Table 2.2 and Figure 2.2. 3.0 .STALLATION DETAILS 3.1 Installation Details/Comparison with Specifications The FORACS target was a package provided by APL and installation went as planned. No changes in the design were required. However, there was a break in the cable during the installation of the shallow FORACS target at AUTEC. The splice to reconnect the cable * is in the cable trench well on shore. What was learned from this experience is that the shallow FORACS targets are diver repairable. . , By simply removing the bolts from the chamber flange connection and disconnecting the underwater mateable connectors, the chamber can be brought to the surface. All location changes were as a result of water depth requirements and agreed to by APL. A comparison between the planned and the installed locations is shown in Table 2.1. 7 I>o 0- N i 0 0 4 N 14 N 1 L) 0 00 '0 0' H ON q k E-Z 0 m cl I-4Q inI 14 H4 0 " N LO %0 m~ OD ai 0 E4 -4 0 0 cv 0 H 000 0 (n N 0 0 0% N0 (u H 04 r4 N r4 - 0 0. 0. 4) ' M z Z n 0% 0- 0 0 0 0 %Dr N 0 0 Ho 0 4.) I-,4 E-4) E-0N i 0 0 0 0 H - rLi 0 0% 0 % a U) U, W E- U 0 E-4 0 0) E-4 0-4 6-3a 0 z- 0 U0 0 opt U,% Y-,Ui -- 4ltb NORTH TOWER CS50 X '430 UNEXPOSED 1 5 ISO Y L#-7625 R FEEF 10 N INTUMFNT TOWER X -13617 Y-3861; JbUU AUTEC ANDROS ISLAND uS VI 5000 1&~ 19000 21000 KEV 4 PRCrjSED LOCATION DEPTH IN FATHOMS +INSTALLED LOCATION A17TEC Installations Figure 2. 1 9 -I, %._ m PLANNED LOCATION INSTALLED LOCATION SITE X (E) Y (N) X Y SPRAT 61,998 37,859 61,998 37.859 COAST GUARD LIGHT 64,850 28,375 64,850 28.375 DEEP FORACS TARGET 58,302 28,774 58,487 29.521 - HOLD POINT FOR DEEP LFTS 60,400 36,975 60,610 36,985 SHALLOW FORACS TARGET 60.334 34.225 60.584 34.311 HOLD POINT FOR SHALLOW LFTS 60,400 36,975 60,722 37.290 HOLD POINT FOR SSRNM ARRAY 60,279 37,333 60,623 37.054 SSRNM ARRAY 52,986 35,029 53,063 35,023 Note: All coordinates are in feet. °% -' ST. CROIX INSTALLED LOCATIONS Table 2.2 10 4; _ - , .' ;' ', * , - ' w# -. '"z - , ,, . w,, . . . . ," ' E50000 E 60000 _____ ____N 140000 Y= 3L7859 SSRNM Y=3528375 0/ * ~ ~ ~ : PRPOE TARGE LOATO DETHIRFT O n ~ ~ ~ ~ ~ ~ OA MIIRNESHOESAINX 066 S.3 Cri 34s3ll4ion Figure02.2 11 AC X=58487' J % The SSRNM array, see Figure 1.2, was changed from the original r considerations: A. The original design was based on a 3000 ft water depth, the selected site was only 2700 ft. and required that 300 ft of Kevlar % strength member be cut off and the Keviar reterminated. B. The triangular termination device was modified to hold the extra electrical array cable (300 ft) and provide a better strain relief system. See Figure 3.1. btC. Due to the break in the Kevlar strength member a splice between two Kevlar lengths exists about 100 ft above the clump. D. While attempting to install the pinger. the back plate of the support bracket was lost over the side. No spare was available so the pinger was not installed. If needed divers can install a new pinger, but depth capabilities to 200 ft will be required by the divers used because the pinger pigtail came up approximately 50 ft short of the bottom of the buoy and not the 5 ft as planned. E. The double buoy system was welded together as well as bolted. -VK F. The location of the SSRNM is off by 77 ft to the east. G. The depth of the top of buoy was measured by diver at 142 ft, 28 ft deeper than measured by the lowering line during the installation. The obvious answer as to why the depth is different than when plumbed and measured is due to the location difference. However this does not explain why the bottom of the buoy measured 122 ft deep during installation and 150 ft deep the next day. This is due to the stretch of the Kevlar whilc supporting the 9.600 lb weight less the 4,200 lb buoyancy from the float holding up the , array. At 1% stretch, this amounts to 26 feet which is close to the 28 ft observed. 4.0 RECOMENDATIONS FOR FUTURE SSRNM INSTALLATIONS 1. All components should be assembled and pressure tested and electronically tested prior to installation operations. The strength member should be marked for hydrophone locations not just length indications. 2. All components should be designed to take installation loads not just installed loads. 3. When depth is as critical as the specifications stated, a better method of placing the array at the desired depth should be developed. This may require a redesign of the array itself, such as using a two-point spread moor rather than the single point moor that ... . was installed. S-*.. *-, 12 -c .. .- -H--. -44 U m E/ 0 4.-4 co~ -Il U-'\ 41- 0_ ~ '-4 1-4 caHp. ~~No -H e~13 r r.- n. r"r -- . . 4. For all ocean operations, have spares for everything, especially I small pieces that are being handled over the side of the vessel. 5. Mark length of electrical cable (every 100 ft). 6. The array electrical cable length should incorporate a given percentage of slack in order to accommodate a tension free connection to the mechanical cable. 7. Mark length of shore cable (every 1000 ft or .1 NM). 8. Reduce in-air weight/size of clump to make installation handling easier. D14 'p.. - [ .. I. , ' [., "' " [ -,,, -14 9 9 9 K 5'. L. S.. "a ~S ~ %~s.s.~* * ~ -~ ~'v~' *;; ~., .~. - - . - -.. '-.- - -. *~~~'~S~S.~~-~.