The deck log,
written the way the watch is kept.
Offline on the ship. Signed before it is official. Ready when the surveyor asks.
Written from the bridge. At sea since 2002, deep-sea master since 2018.
Real screens from a sample vessel. Sample values, not a real voyage.
The paper log is honest. It is also slow, and it is hard to search.
Corrections, strike-throughs, handwriting at 0400
A wrong figure gets a single line and initials. After a heavy-weather watch the page is correct and almost unreadable, and the next officer has to work out what the handover actually said.
The same noon position typed four times
Deck log, noon report, the office email, the charterer's form. Each copy is one more place for a transposed digit, and nobody can say which one was first.
Flipping pages while the inspector waits
"Show me the steering gear tests for the last two weeks." The entries exist. Finding them across three books and two months, with the PSC officer standing at the chart table, is the hard part.
One record. The ship writes it, the office reads it.
The ship keeps working with no internet. The office gets a copy, not the right to overwrite a signed entry. Designed to the electronic record principles of MEPC.312(74).
The ship does not wait for the satellite.
Every entry is written on board first. A lost link, a slow VSAT or a dead office server does not stop an entry or a signature. On conflict, the ship's signed entry wins and the office change is kept as a separate revision. Try it:
Officers record.
NMEA 0183 and Signal K (UDP, TCP, serial) fill a draft with time, position, course, speed, wind and depth. The source is shown on the line. A sensor reading is never the official record until the officer confirms it. Direct NMEA 2000 and engine hours are on the roadmap.
Try to change a signed line.
Each entry carries the hash of the one before it. Edit a value and watch the chain break from that line onward. Real SHA-256, running in your browser.
Day, Twilight, Night.
Night mode has no white and no blue light. The choice is remembered per station.
A signature belongs to its owner.
A personal 4–6 digit PIN, stored as an Argon2id hash on the ship only. Wrong PINs lock the account for 5 minutes, then 15, then an hour. Deck pages: officer of the watch or Master. Engine pages: duty engineer, Chief Engineer or Master. The Master and Chief Engineer countersign.
A synced copy, never the right to overwrite.
Fleet dashboard, alerts for missing watch entries, late countersignatures, unread orders and stale sync. Office corrections become separate, named revisions with a reason. Crew accounts and one-time temporary PINs are issued here. Not a fleet-performance or voyage-optimisation suite.
From Deck Log to MARPOL.
For merchant ships, not yachts. Every book prints as a page-by-page PDF in a layout that follows the printed book. The PDFs are not presented as exact IMO forms.
Bound to the computer.
An offline signed licence ties the installation to its ship and hardware. Without a valid licence the log stays readable and PDFs still print, but no new records close.
A voice note will open a draft, nothing more.
Not built yet. The design: it does not lock until the officer has read and signed it, and a transcription that invents something never reaches the audit trail.
Pick the days the inspector asked for. Hand over a closed package.
Audit mode builds a fixed record for a chosen date range: an unchangeable PDF in the page layout a surveyor expects, the hash chain that proves nothing was edited afterwards, every signature, and who entered each line.
Port State Control usually asks for a specific window: the last 14 days of steering gear tests, the arrival draft, the passage plan check. Choose the range, print or send the PDF, and keep looking at the officer, not the pages.
- RangeAny span of days, fixed at export. Later revisions are listed, not merged in.
- DocumentRead-only PDF, laid out like the paper book page by page.
- IntegrityEach entry carries the hash of the one before it. Each page carries a seal chained to the page before, and a QR code to check it.
- SignaturesOfficer of the watch, master, and any office revision with name, time and reason. A changed countersigned page prints as not valid.
- ProvenanceFor every value: typed, sensor draft or checklist, and who confirmed it.
Illustrative package. Hashes and names are placeholders.
If the office copy's chain is broken, nothing is shown and no PDF is made.
One ordinary computer. No special hardware.
The ship server runs in Docker on a PC or small server on the ship's network. Bridge PCs and tablets open it in a browser over HTTPS. Installation and operator guides are written in English and Turkish.
Fill in the ship
IMO number, server name and the ship's time. The IMO identifies the record chain and is never changed later.
Start the services
Server, bridge screen, updater and an HTTPS door with the ship's own certificate authority. They restart by themselves after a power cut.
Trust the certificate
Install it once on each bridge PC and tablet. No browser warnings, and still no internet.
The Master takes over
First account, vessel particulars and the NMEA feed, saved with the Master's PIN. Licence and updates are signed.
NMEA, tested before it is saved
NMEA 0183 over UDP, TCP or serial, or Signal K. If the feed is lost, the screen blanks position and speed instead of showing an old value.
Crew assigned from the office
The office issues a one-time temporary PIN, shown once. A temporary PIN cannot sign; the user sets their own on first sign-in.
Written for the people who install it and the people who sign with it.
Installation Guide
Ship server, first start, NMEA, licence, office sync and updates.
Open → English · PDFOperator Guide
Signing in, entries, approving, PIN signing, countersigning, checklists, orders, reports.
Open → Türkçe · PDFKurulum Kılavuzu
Gemi sunucusu, ilk başlatma, NMEA, lisans, ofis senkronu ve güncellemeler.
Aç → Türkçe · PDFOperatör Kullanım Kılavuzu
Giriş, kayıt, onay, PIN ile imza, kontra imza, kontrol listeleri, raporlar.
Aç →Not class approved. Not flag accepted. Here is the order we intend to apply.
The design follows the electronic record book principles of IMO resolution MEPC.312(74).
Type approval and flag acceptance are applied for only after the ship system is stable on board. Until then, the paper book stays the official record.
- Now
Design to MEPC.312(74)
Signatures, audit trail, tamper evidence and export built in from the first entry.
- Next
Deck log stable on board
Trial vessels run it alongside the paper log until watchkeepers trust it.
- Then
Apply for type approval
Application to a classification society for the deck log, once the ship system is stable.
- Then
Apply for flag acceptance
Applications flag by flag, following each administration's own process.
- After
Engine and MARPOL books
Engine log, ORB I/II, Garbage and Ballast Water record books, through the same steps.
If you need an approved electronic log on board today, NAVTOR and NAPA have type approvals and flag acceptances in place and are proven across large fleets. We are building something narrower: a deck log shaped by the watch, offline first, with the ship's signed entry as the record.
Recep Oğuz Yağbasan
Written from the bridge. At sea since 2002, deep-sea master since 2018.
Pelorus is built by a serving merchant master who has kept the deck log as a cadet, as officer of the watch and as master, and has opened it for port state, flag and class inspections more times than anyone keeps count of.
The screens follow the paper book because that is how watchkeepers already think. The rules come from the bridge: nothing becomes official until an officer signs it, and nothing the office does can quietly change what the ship signed.
LinkedIn Recep Oğuz YağbasanTell us about your ships.
We are looking for a small number of operators to run the deck log on board alongside the paper book.