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When the ESSO DEN HAAG entered service for Esso-Nederland in ‘I963, she became the Jersey fleet‘s first 90,000 dwt. bridge-aft tanker. Because the ship represented a radical departure from Esso-Nederland's existing vessels both in design and size, the
company has observed the ESSO DEN HAAG’s operating experience with keen interest.
The followin article discusses some of the reasons why Essa-Nederland chose the bridge-aft design and reports on its experience with the vessel during its first two years of operation. - Editor

Esso-Nederland N.V.
TWO important decisions regarding the ESSO DEN HAAG were made while the ship was in the early stages of construction at Verolme United Shipyards, Rotterdam: to employ the bridge-aft design and to coat the vessel inside and out during her onstruction.

We chose the all-aft arrangement because we believed it promised these signi?cant advantages:
* Increased crew safety
* Improved morale and comfort (by locating all quarters, messrooms and recreational facilities in one structure)
* Reduced maintenance costs
* Manpower savings.

Before the ?nal design decision was made, it was argued by some that these advantages might be offset by unforeseen navigational difficulties, and we were urged to first gain experience with the bridge-aft design on a smaller class tanker, such as 47,000 dwt. We had not heard of unfavorable navigational experiences with this type of vessel outside the Iersey fleet, however, and we were confident that within a few years large vessels with all-aft superstructure would render the conventional design obsolete. We felt that the all-aft design would add to the comfort and convenience of the ship’s complement and that, by removing the midships structure, we would also eliminate the maintenance work associated with it.

With these thoughts in mind, we discussed our design with the Dutch Shipping Inspectiona government authority similar to the U.S. Coast Guard — which had no objections.
During the trial trip, it became apparent that our decision was well founded. The builder’s trial crew experienced no difficulty in handling the ESSO DEN HAAG. Of course, the view is restricted in comparison to that from a bridge located amidships, a fact which we compensated for by installing on an experimental basis a closed-circuit television system between the bow and bridge.

The camera and display unit were manufactured by Philips N.V., Eindhoven. We got a favorable impression of the camera, which was of a light and sturdy design, and the display unit proved to be of a good design. On the minus side, we found during the ESSO DEN HAAG’s sea trials that the television system provided a limited viewing area, that it provided no ranging system and that its use was restricted to daylight hours.

While these three problems could undoubtedly have been overcome, we decided not to continue the tests after the trials. This decision was based on the fact that during maneuvers in port and other restricted areas - where television should have been most helpful - the master and pilot received sufficient information from the forward and aft lookouts to make the system unnecessary.

Now, after two years’ service, our masters confirm that there is no real need for television on a 90,000 dwt. bridge-aft vessel. Of far more importance to the safe handling of a ship like the ESSO DEN HAAG is a good communication system between the bridge and mooring stations.
Discussions with pilots at various ports and the experience gained during maneuvering in the Suez Canal, New Waterway to Rotterdam, at bow moorings and sea berths have indicated that the navigational disadvantages, if any, are negligible. In open water the view from the bridge represents no hazard, since it is always advisable to avoid close-quarter conditions with
vessels this size.

A detailed description of the coating work carried out during construction of the ESSO DEN HAAG is contained in Vol. 8, No. 4 of ESSO MARINE NEWS. The total area involved was about 1,500,000 square feet.
The first full-scale inspection of the ship’s coated surfaces - after the vessel had been in operation for a year - showed that the coating in the cargo compartments effectively resisted crude oil attack. Damage to the intemal surfaces was negligible, although a few zinc anodes were installed to cathodically protect some areas.
On the outer hull, only damage to the coating caused by the anchor chains had to be retouched; no fouling occurred.
It has also been found that tank cleaning and gas freeing operations can be accomplished faster and easier than on vessels with uncoated tanks.

As the ESSO DEN HAAG enters its third year of operation, it is obvious that the bridge-aft design and widespread use of coatings during construction have made it possible for us to meet our objectives of reducing maintenance costs and manpower. The vessel is presently operating with a 35-man crew, with additional reductions possible in the future.