orientation. Deployment is shown in Figure 9. The anchor was then 

 fired, the launch vehicle and the piston were retrieved, and the anchor 

 proof-loaded to at least 100,000 pounds (450 kN) . The installation 

 sequence is shown in Figure 10. The connection to proof- loading gear 

 and the subsequent attachment to the chain to complete the mooring 

 hookup were conducted at or above the sea surface. 



In order to recover the piston, divers were required to make a 

 connection between the piston retrieval line and a traveling block on 

 the barge's 1-inch (25 mm) wire. This requirement could have been 

 avoided by using a longer line to the piston, or by preconnecting the 

 block or a larger haul-in line to the piston retrieval line before 

 anchor deployment; however, such an approach would have increased the 

 complexity of the deployment operation. The piston retrieval operation 

 was time consuming, even with the ample diver assistance available, and 

 required the use of two winches, the beach gear, and the crane; hence, 

 it was operationally expensive. 



With this in mind, the piston retrieval operation was omitted from 

 an early shot, and the satisfactory keying of the fluke and development 

 of holding capacity were verified, at least for the materials at the 

 reported site. Pistons also were not recovered on several of the final 

 installations to save time and to expend the used pistons that were 

 showing some erosion on their outer surfaces due to blow-by of the 

 abrasive propellant. When piston recovery was not attempted, diver 

 assistance was not required. 



INSTALLATION OPERATIONS SUMMARY 



Within 2 weeks, 18 propellant anchors were installed at Diego 

 Garcia, 10 for the permanent POL mooring and 8 for the temporary POL 

 mooring. Two fluke sizes and two types of propellant were used during 

 the installation. A log of the installation operations is in the Appendix. 

 Highlights are discussed below. 



Listed in Table 1 are some of the data resulting from the 19 firings. 

 Listed data consist of: installation at either the permanent site or 

 the temporary site (designated by a ««P" or ''T' 5 , respectively), along 

 with the installation order at each site, the nominal fluke size used, 

 the charge weight, the propellant type, the peak gun pressure, the 

 anchor penetration depth, the peak recovery force required to retrieve 

 the piston, and the approximate peak anchor proof- load. Anchors were 

 proof -tested to at least 100,000 pounds (450 kN) . Most anchors sustained 

 peak proof- loads between 100,000 (450 kN) and 120,000 pounds (530 kN) , 

 although a few of the anchors sustained higher peaks caused by surge, 

 with the highest being 165,000 pounds (730 kN) . One anchor was proof - 

 tested statically during calm conditions to 150,000 pounds (670 kN) . 



16 



