NEWS AND COMMENT

BRUCE DENNLA - RECOVERY FROM SOFT CLAY.

  1. Receive chaser pendant from MODU and secure in shark's jaw.
  2. Connect 1st work-wire to chaser pendant.
  3. Haul in on 1st work-wire to take load off shark's jaw and then lower shark's jaw.
  4. Pay out length of 1st work-wire equal to 1. 05 times water depth at the embedded anchor while boat tows chaser towards anchor.
  5. When the load in 1st work-wire starts to increase, as the chaser reaches the inverse catenary of the anchor fore-runner at the mud-line, stop the boat and instruct the MODU winch to pay out 50m of anchor line.
  6. Haul in 50m of 1st work-wire to raise a bight in the anchor line off the seabed.
  7. Move boat beyond the anchor position while paying out 50m of 1st work-wire as MODU winch pays out a further 50m of anchor line to allow the bight to be dragged beyond the anchor position.
  8. Apply boat power away from the MODU to rotate and slide the Dennla shank to the rear of the fluke to break the Dennla backwards out of the seabed. The tension in the 1st work-wire drops as the anchor breaks out and the remaining tension in the anchor line pulls the chaser stopper into engagement with the chaser.
  9. With sufficient boat power maintained away from the MODU, haul in on 1st work-wire until chaser pendant is on deck and chaser chain is on stern roller.
  10. When chaser chain appears on roller, veer boat to bring anchor line parallel with roller before chaser reaches roller to ensure that chaser traverses roller on its side.
  11. As the anchor comes over the roller (with the shank pivot pin at the after end of the fluke central plate slot), adjust veering of boat to keep the anchor line clear of the anchor.
  12. Bring anchor up deck and veer boat to bring anchor line over shark's jaw.
  13. Raise shark's jaw and pay out 1st work-wire until anchor line is held in shark's jaw then stop 1st work-wire.
  14. Pass a tugger slip line through anchor shackle.
  15. Shackle 2nd work-wire to anchor fluke central plate forward lug.
  16. Haul in on 1st work-wire to take load in anchor line and then lower shark's jaw.
  17. Veer boat to bring anchor line alongside fluke central plate.
  18. Pay out 1st work-wire and tugger slip line simultaneously to bring anchor onto roller.
  19. As anchor starts to topple over roller, reduce pay out speed of 1st work-wire to allow weight of anchor to straighten the connection between stopper and anchor then stop all paying out.
  20. With anchor weight taken by 1st work-wire, slip tugger line off anchor shackle.
  21. Pay out 1st work-wire to lower anchor over roller and bring chaser onto roller.
  22. Veer boat to hold chaser on its side as it passes over the roller and stop 1st work-wire when chaser chain end is on roller.
  23. Haul in about 4m of 2nd work-wire to bring anchor shank pivot pin to the forward end of the slot in the fluke plate.
  24. Brake 2nd work-wire.
  25. While maintaining the veered heading of the boat, haul in on the 1st work-wire to bring the chaser over the roller on its side.
  26. Continue hauling in on the 1st work-wire to bring the anchor over the roller onto deck while adjusting the veering heading of the boat to keep the anchor line clear of the anchor.
  27. Pull the anchor up the deck with the 1st work-wire and veer the boat to bring the anchor line over the shark's jaw.
  28. Raise the shark's jaw and stop hauling in 1st work-wire.
  29. Pay out 1st work-wire until anchor line is held in shark's jaw and then stop pay out.
  30. Unshackle 2nd work-wire from anchor fluke central plate forward lug and tug it clear of anchor.
  31. Remove any portions remaining of parted shear pin.
  32. Pass tugger slip line through anchor shackle.
  33. Haul in on 1st work-wire to take load in anchor line and then lower shark's jaw.
  34. Veer boat heading to bring anchor line alongside anchor fluke stabiliser.
  35. Pay out 1st work-wire and tugger slip line simultaneously to bring anchor onto roller.
  36. As anchor starts to topple over roller, slow pay out speed of 1st work-wire to allow weight of anchor to straighten the connection between stopper and anchor then stop all pay out.
  37. With anchor weight taken by 1st work-wire, slip tugger line off anchor shackle.
  38. Pay out 1st work-wire to lower anchor over roller and bring chaser onto roller.
  39. Veer boat to hold chaser on its side as it passes over the roller and stop 1st work-wire when chaser chain is on roller.
  40. Veer boat to bring chaser chain over shark's jaw.
  41. Raise shark's jaw.
  42. Pay out on 1st work-wire until load in chaser chain is taken by shark's jaw and then stop 1st work-wire.
  43. Back up boat to MODU as MODU winch hauls in anchor line.
  44. When boat is less than chaser pendant length off the MODU, hold boat position and lower shark's jaw to transfer tension control to 1st work-wire.
  45. Pay out on 1st work-wire as MODU winch hauls in anchor with paying out and hauling in speeds matched.
  46. When the mark on the anchor line is aligned with the corresponding mark on the MODU (verified by the MODU winch operator), pay out on the 1st work-wire to bring the anchor shackle into contact with the MODU bolster bar and then stop 1stwork-wire with the chaser pendant slack.
  47. The MODU winch now hauls in slowly on the anchor line to pull the anchor shank up over the bolster bar. The Dennla turns automatically to bring the flat side of the shank against the bolster bar and then the racking nibs on the fluke into engagement with the bolster bar. The MODU winch now stops and applies the brake with about 20mT tension to hold the Dennla securely on the bolster bar.
  48. Veer boat to bring chaser pendant over shark's jaw.
  49. Raise shark's jaw.
  50. Pay out 1st work-wire until chaser pendant is held in shark's jaw and then stop 1st work-wire.
  51. Disconnect 1st work-wire from chaser pendant and haul clear.
  52. Receive MODU crane line and connect to chaser pendant.
  53. Lower shark's jaw as MODU crane picks up chaser pendant for storage on MODU.