were located in over 5,000 feet of water approximately 10 miles west of Hydrographer Can- 

 yon. 



ALVIN was being lowered over the side when two steel cables on the launch cradle of 

 LULU snapped, causing ALVIN to plunge forward into the water. As ALVIN plunged into 

 the water, LULU's crew members held on to heavy nylon retaining lines, which had been 

 attached to the side of ALVIN during launching. Simultaneously, LULU's captain moved 

 the catamaran forward providing clearance for the three-man crew inside ALVIN. ALVIN 

 sank below the surface and popped up again allowing the three men inside to scramble safely 

 out onto the side of LULU. ALVIN was down by the bow and flooding rapidly through a 

 broken forward observation window in her conning tower (figure 1), thence through an open 

 pressure sphere hatch. The retaining lines snapped, and the 15-ton submersible plunged to 

 the ocean floor. GOSNOLD and LULU remained at the scene for 2 days following the acci- 

 dent. They made a careful survey of the area and narrowed the search site to 1 square mile. 

 ALVIN's position was estimated as latitude 39°53.5' N and longitude 69°15.5' W. (Refer 

 to Appendix A, figure A-1, a chart of the loss area.) 



The extent of damage sustained during the mishap could not be fully known until 

 ALVIN was found and raised. However, ALVIN's stern propeller was observed to have 

 been knocked off during the accident, and it was felt that there might have been other dam- 

 age to the stern area, which encloses the trim tanks, buoyancy controls, and the steering 

 propulsion mechanism. 



Salt water damage to the instrumentation in the pressure sphere was expected to be 

 extensive. The depth to which ALVIN had sunk was not a factor in estimating damage, as 

 she was capable of dives to 6,000 feet. (For detailed vessel characteristics, refer to Appen- 

 dix B.) The bottom was thought to be firm clay covered by silt, and impact damage would 

 depend on the exact angle and speed with which she hit bottom. The consensus was that 

 she dropped at a speed of approximately 10 knots, at a 45° to 60*^ nose-down angle, and 

 wdth hatch open. 



An operation to recover ALVIN was initiated immediately. The DRV DOWB and 

 R/V CHAIN were used; however, difficulties with DOWB and the onset of North Atlantic 

 winter caused the operation to be terminated on 23 November 1968. 



In the ensuing months, further consideration was given to the recovery of ALVIN. The 

 following factors were considered adequate to justify planning a salvage operation for 1969: 



