# Sailcasted — Celestial Navigation Training Platform (Full Reference)

> Sailcasted is a celestial navigation training platform. Students enroll in simulated ocean passages ("traversées"), receive daily astronomical observations by email, solve sight reduction problems on paper, and submit their calculated position. The system computes the delta in nautical miles between the student's fix and the actual position. This is NOT a navigation course — it is a practice tool for sight reduction skills.

## Key Facts
- Observations computed from USNO/JPL ephemerides (±0.5' accuracy)
- Supports HO 249, AP 3270, HO 229, and SHOM reduction tables
- 4-tier progression system (Beginner to Captain)
- Free passage available: Halifax → Bermuda (7 days)
- No software required — observations delivered by email
- Magic link authentication — no passwords
- Cohort mode for instructors
- Bilingual platform (English and French)
- Virtual Sextant PWA for real-time GPS-based practice

## Tier Progression System

### Tier 1 — Beginner (Matelot)
- Celestial bodies: Sun only
- Accuracy tolerance: ±30 nautical miles
- Focus: Learning the basics of sight reduction — altitude corrections, GHA/declination lookup, intercept method

### Tier 2 — Sailor (Officier de quart)
- Celestial bodies: Sun, Moon, Polaris
- Accuracy tolerance: ±15 nautical miles
- Focus: Multiple body observations, running fixes, and Moon sight reduction with additional corrections (HP, SD)

### Tier 3 — Officer (Officier navigateur)
- Celestial bodies: Stars, Venus, plus all Tier 2 bodies
- Accuracy tolerance: ±10 nautical miles
- Focus: Star identification, twilight planning, multi-star fixes, and planet observations

### Tier 4 — Captain (Capitaine)
- Celestial bodies: All navigational bodies including eclipses
- Accuracy tolerance: ±8 nautical miles
- Focus: Mastery-level precision, unusual phenomena, and complete self-sufficiency in celestial navigation

## Complete Passage Catalogue (21 passages, 425 days)

### Northern Hemisphere — Bundle Nord (49$ CAD, 8 passages)
- Halifax → Bermuda (7 days, Tier 1-2, FREE) — Gulf Stream, VHF fix
- Carolinas → Bahamas (7 days, Tier 1-2) — Cape Hatteras, Gulf Stream
- Europe → Azores (10 days, Tier 1-2) — Radio Manuel, Pico visible
- Classic Atlantic East → West (28 days, Tier 1-3) — IC incident, chrono drift, Moon+Polaris
- Hawaii → California (14 days, Tier 2) — Pacific High, Golden Gate
- Viking Route Bergen → Newfoundland (21 days, Tier 2-3) — Icebergs, high latitude, Polaris at 62°
- Canaries → Caribbean ARC (21 days, Tier 2-3) — Trade winds, ideal for instructors
- Pacific Asia → Hawaii (21 days, Tier 2-3) — Date Line, great water desert

### Southern Hemisphere — Bundle Sud (49$ CAD, 7 passages)
- South Atlantic Brazil → Cape Verde (21 days, Tier 2-3) — Equator crossing, reversed azimuths
- Indian Ocean Réunion → Australia (18 days, Tier 2-3) — Roaring Forties, Canopus, albatross
- South Pacific NZ → French Polynesia (14 days, Tier 2-3) — Date Line, milk run, noddy
- Cape Town → Brazil (21 days, Tier 2-3) — Agulhas Current, South Atlantic return
- Australia → New Zealand Tasman (10 days, Tier 2) — Cold fronts, consolidation
- Madagascar → Réunion (7 days, Tier 1-2) — Entry-level Southern Hemisphere
- Ushuaia → Cape Town (28 days, Tier 3-4) — Screaming Fifties, extreme conditions

### Equatorial Crossings (Bundle Complet only)
- Hawaii → Marquesas (18 days, Tier 2-3) — ITCZ, Polaris farewell, Southern Cross
- Canaries → Brazil (21 days, Tier 2-3) — Atlantic diagonal, two hemispheres
- Polynesia → Hawaii (18 days, Tier 2-3) — Reverse ITCZ, Polaris returns

### Premium — Bundle Complet (89$ CAD, all 21 passages + dynamic events)
- World Tour (90 days, 5 acts, Tier 3-4) — Circumnavigation: Gibraltar → Cape Horn → Pacific → Gibraltar. Recurring characters, narrative arc, all astronomical challenges.
- Lost at Sea (dynamic) — Recurring random challenge. Unknown position, 3 observations, determine location + bearing to nearest port. Frequency: weekly/bimonthly/monthly.
- Solar Eclipses (dynamic) — Real astronomical events. Simultaneous Sun+Moon observations for instant fix. Sent to Bundle Complet owners when actual eclipses occur. Next: August 12, 2026.

## How Enrollment Works

### Free Passages
1. Enter email → receive confirmation link → click to confirm → choose start date → enrollment created
2. Returning verified users skip confirmation

### Paid Passages
1. Enter email → confirm → Stripe Checkout (automatic tax) → enrollment created on payment
2. Gift code / promo code support (validated against Stripe Coupons)

### Bundle Purchase
1. Purchase creates access (12 months) but does NOT auto-enroll in all passages
2. Student activates each passage individually from their dashboard with a chosen start date
3. Dynamic events (Lost at Sea, Eclipses) activate automatically

### What Happens After Enrollment
- All astronomical observations for the entire passage are pre-computed using USNO/JPL ephemerides
- J-1 preparation email: "Your passage starts tomorrow — make sure you have your materials"
- Each day at 06:00 in the student's timezone, an email arrives with that day's observations
- The student reduces the sights on paper using their preferred reduction tables
- The student submits their calculated latitude and longitude via a magic link in the email
- The system computes the Haversine distance between the submitted fix and the actual position
- After 3+ days with no submission, an inactive nudge email is sent
- Students can postpone their start date if not ready

## Pricing

### Individual Students
- Free passage: Halifax → Bermuda (7 days) — no credit card required
- Individual passages: 19$ to 49$ CAD (one-time, 12-month access)
- Bundle Nord: 49$ CAD (8 passages, Northern Hemisphere)
- Bundle Sud: 49$ CAD (7 passages, Southern Hemisphere)
- Bundle Complet: 89$ CAD (all 21 passages + Lost at Sea + Solar Eclipses + World Tour)

### Instructors
- Base plan: Free — 1 cohort, 12 students, limited passage selection
- Pro plan: 79$/year — unlimited cohorts, unlimited students, all passages, CSV export, priority support

## For Instructors

### Cohort Mode (Simulation)
- Create a cohort and invite students by email or shareable link
- Passages assigned to students are free for them
- Track progress via color-coded heatmap dashboard (green/yellow/red based on accuracy)
- Affiliate commission on student purchases

### Workshop Mode (Atelier)
- Dispatch observations manually instead of daily automatic schedule
- Students have 7-day submission window (vs 48h in simulation)
- Step-by-step HO 249 calculation fields in submission form (13 fields)
- Compare all students' submissions side-by-side for a given day
- Annotate individual submissions with instructor feedback
- Flag submissions as case studies for group discussion

### Supported Certifications
- Transport Canada — Marine certification (TP 15136F)
- RYA — Yachtmaster Ocean
- USCG — Master/Mate licenses
- STCW — Officer in Charge of Navigational Watch (OICNW)
- FFVoile / Marine marchande française — Capitaine 200/500/3000
- IYT — Master of Yachts 200 GT

## Technical Details

### Astronomical Engine
- Ephemeris source: USNO/JPL DE440 planetary and stellar ephemerides via Skyfield
- Accuracy: ±0.5 arcminutes for computed altitudes
- Bodies supported: Sun, Moon, Venus, Mars, Jupiter, Saturn, 57 navigational stars, Polaris
- Special: Eclipse pipeline (simultaneous Sun+Moon), multi-body batch, twilight calculator
- Corrections: refraction (Bennett), semi-diameter, dip, index correction, HP (Moon), augmentation
- Modifiers: refraction anomaly, IC shift (sextant shock), chronometer drift

### Position Comparison
- Algorithm: Haversine formula for great-circle distance
- Unit: Nautical miles (1 nm = 1 arcminute of latitude)
- Also computes: bearing to destination (for Lost at Sea challenges)

### Observation Delivery
- Format: Celestial body, UTC time, 3 Ho readings (with noise based on sea state), IC, Dip, SD
- Timing: YAML-defined or computed from longitude (solar noon, twilight for stars)
- Special days: Dead reckoning (no observations), VHF fix (position check from passing vessel)
- Narrative: Bilingual journal entries with world-building elements (fauna, weather, characters)

### Virtual Sextant
- PWA at /virtual-sextant — installable on mobile
- Uses phone GPS (hidden from user) to generate real observations
- Student does sight reduction on paper, submits fix, gets delta in nm
- No login required — works for anyone

## Frequently Asked Questions

### What do I need to get started?
Sight reduction tables (HO 249, AP 3270, HO 229, or SHOM), a Nautical Almanac for the current year, a worksheet, and a pencil. No sextant, no software, no GPS.

### Is this a navigation course?
No. Sailcasted is a practice tool, not a course. It provides realistic observations for you to reduce — it does not teach the theory. You should already understand the basics of sight reduction, or be learning alongside a course or instructor.

### How are the observations generated?
Computed from USNO/JPL ephemerides with realistic atmospheric corrections. Random noise simulates real sextant reading variability based on sea state conditions.

### How does the tier system work?
Start at the tier indicated by the passage. Maintain accuracy below the threshold over 7 consecutive days to unlock the next tier. Each tier introduces new celestial bodies and tightens tolerance.

### What is "Lost at Sea"?
A recurring surprise challenge (Bundle Complet exclusive). You receive 3 observations from an unknown ocean position and must determine your coordinates, bearing, and distance to the nearest port. Frequency is configurable: weekly, bimonthly, or monthly.

### What are the Solar Eclipse events?
When a real solar eclipse occurs, Bundle Complet owners receive a special observation with both Sun and Moon visible simultaneously through the sextant — giving an instant fix from two lines of position. Next eclipse: August 12, 2026.

### Can instructors use this in a classroom?
Yes. Workshop mode lets you dispatch observations on your schedule, compare all students side-by-side, and annotate submissions. Passages are free for cohort students.

## Company
Built by Technologies ebbDesk (9322-8310 Québec inc.)
Founded by a Sail Canada certified instructor.
Website: https://sailcasted.com
Company: https://ebbdesk.com
Support: support@ebbdesk.com