Harbour trials, sea trials, redelivery
Commissioning software that carries a vessel from first energisation to a signed delivery certificate.
Harbour acceptance trials and sea trials are where every commissioning gap on a newbuild or major retrofit finally has to answer to physics. Deskely carries the equipment register straight from installation through HAT, SAT and sea trials to delivery or redelivery, so the trials programme is run against known readiness rather than hope.
- Sequence
- HAT, sea trials, delivery
- Parties
- Yard, owner, class, flag
- Output
- Trial results and protocol
- Gate
- Delivery / redelivery certificate
Choose your project type
The problem
Trials expose whatever the commissioning record set left unproven.
By the time a vessel goes to sea, hundreds of systems across dozens of contractors have to be genuinely complete, not just marked complete in a spreadsheet the owner has never seen.
When trial failures trace back to equipment that was never actually commissioned to the required standard, the dispute over responsibility often costs more time than the fix itself.
Deskely carries the full commissioning history into the trials phase, so every system on the trial agenda is backed by the installation and functional test records that should have proven it already.
Setting up the register
The trial agenda and the equipment register are the same structure, not two documents.
Harbour acceptance trial and sea trial agenda items — speed, manoeuvring, endurance, navigation and communication equipment, safety systems, mission equipment — are linked to the underlying equipment tags and their commissioning records.
Trial prerequisites are modelled explicitly, so an item cannot be scheduled for sea trials while the equipment beneath it is still open in commissioning.
This is what lets the trials team plan the agenda against actual readiness rather than the shipbuilding contract's assumed schedule.
Execution
HAT, sea trials and observations recorded against the vessel, in real time.
Yard, owner's representative and class surveyor observations are captured on tablets during harbour and sea trials, against the specific system or equipment being tested.
Punch from trials is raised immediately with photos and categorised by whether it blocks delivery, redelivery or is acceptable to carry with a guarantee obligation.
Trial results — speed, fuel consumption, manoeuvring, DP proving, endurance — are held against the vessel record alongside the commissioning history that led to them.
Delivery and redelivery
The delivery protocol reflects what was actually tested, not what was planned.
The protocol of delivery, or redelivery certificate for a retrofit, is issued from the trial results and the punch position at the time of signing, with carried items listed by owner and date.
The full dossier — commissioning records, trial results, class and flag correspondence, and outstanding punch — passes to the owner as one package rather than a folder assembled the week of handover.
That dossier is also what the owner's technical team uses to manage guarantee claims during the warranty period.
The trial route, the weather window and who is on board
A sea trial is booked once, and if the weather or an unresolved prerequisite loses the slot, the next one might be weeks away.
Sea trials require a booked route, a weather window that meets the trial specification's sea state limits, and every witnessing party — owner's representative, class surveyor, flag state where required — on board on the same day, a coincidence that gets harder to repeat the longer a vessel sits waiting on an unresolved commissioning item.
Losing a trial slot because one system's prerequisite records were not actually closed, discovered only when the surveyor asks for them at the quay, costs the yard the weather window and every witnessing party's calendar, not just the day itself.
Deskely surfaces trial readiness against the same prerequisites the surveyor will ask for before the vessel leaves the berth, so a slipped record is caught days before the trial date rather than at the gangway with the pilot already on board.
How it runs
From last commissioning record to a signed protocol.
Trials are the least forgiving phase of a build programme, which is exactly why they should run on the same register as everything before them.
- 01
Link the trial agenda
HAT and sea trial agenda items linked to the underlying equipment tags and commissioning records.
- 02
Model trial prerequisites
Trial readiness gated on commissioning completion, so items cannot be scheduled while open beneath them.
- 03
Capture observations live
Yard, owner and class observations recorded against the system being tested during the trial itself.
- 04
Categorise trial punch
Findings marked as blocking delivery, blocking redelivery, or carriable under guarantee, with owners and dates.
- 05
Record trial results
Speed, manoeuvring, endurance, DP proving and other results held against the vessel record.
- 06
Issue the protocol
Delivery or redelivery certificate issued from signed trial results, with the full dossier exported to the owner.
FAQ
Questions about Sea trials and delivery scopes.
Keep reading
Marine and shipyard commissioning
The full sector view: build stages, class survey evidence, sea trials and delivery documentation.
Read moreCertificates
Mechanical completion, harbour trial, sea trial and delivery certificates issued from signed records.
Read morePreservation
Routines for machinery and outfit that sits idle between installation and energisation on the berth.
Read moreOther marine and shipyard project types: Newbuild vessel construction and trials, Vessel conversions and module integration, Drydock and repair periods, Cruise and ferry refits, Naval and defence vessel completions, LNG/LPG carriers and gas systems, OSV, PSV, CSV and walk-to-work vessels, Dual-fuel, scrubber and emissions retrofits, Shipyard facility and drydock infrastructure.