With tanker chartering, it is often the case that the owner of a tanker exceeding the stipulated timecharter performance, is rewarded by payment of extra hire reflecting the financial extent of the better performance. Only rarely is this the case with dry-cargo chartering, although there is no reason why dry-cargo ships should not be similarly assessed. In fact, although it would create an additional workload for those entrusted with performing the calculations, with the aid of computer technology this is no longer the chore it once was, and there is less reason for shipowners to misdescribe their vessels during negotiations leading to a fixture, if they are to be rewarded any way for enhanced performance in accordance with the timecharter value of their vessel. Consequently, there is every reason to ‘borrow’ one of the tanker industry’s good ideas. Lines 190 to 195 of the ASBATIME refer to diversions from a vessel’s planned course, and it is necessary for those involved in this area of shipping to familiarise themselves with simple deviation calculations used to assess the costings of off-hire incidents. In the following example, let us assume that our vessel is deviating to land a sick seaman (the cost of which, incidentally, should be covered under the terms of an owner’s P & I insurance cover) or, perhaps, is proceeding to a dry-dock for routine repairs. Let us also assume that both incidents are clearly off-hire and the only problem is for the parties to calculate the time spent off-hire and the quantity and cost of excess bunkers consumed. The deviation is normally calculated by the Master and sent directly to both his owners and charterers or to charterers via his owners and will cover extra time and bunkers used. From the actual time used to deviate from Point A to Port/Drydock and to return to Point B (including all time spent in Port/Drydock) must be deducted the estimated time that would have been taken if steaming as per timecharterers’ instructions from Point A to Point B direct. The difference is off-hire. These figures can be checked by timecharterers, even if they employ no-one with sea going experience, by dextrous use of marine distance tables which, although possibly not entirely accurate, will give a close approximation.