— Certification
The International Convention on Standards of Training, Certification and Watchkeeping (STCW) requires officers to demonstrate competency in celestial navigation as part of OICNW certification. This is recognized by all IMO member states.
STCW competency Table A-II/1 requires the ability to use celestial bodies to determine position. Assessment includes practical demonstration of sight taking and reduction.
HO 229
Sailcasted simulates realistic ocean passages. Every day, you receive an astronomical observation by email — just like at sea. You reduce it with your tables (HO 229), calculate your position, and submit your fix. The platform calculates your error in nautical miles.
Observations are generated from USNO/JPL ephemerides with ±0.5 arcminute accuracy — the same precision as official nautical almanacs.
Sailcasted passages are organized into 4 tiers of increasing difficulty. Start at Tier 1 with simple observations (sun only) and progress to Tier 4 with complex observations (stars, planets, challenging conditions).
To prepare for your STCW exam, you will need:
Try free with the Halifax — Bermuda passage. No credit card required.
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