Drift Modelling Simulation Experience Suite

Drift Parameters

Input field Calculated (read-only)

Formulas are shown beside calculated fields and worksheet lines.

Selected method(s): only enabled drift models run, and output layers are rendered for each selected model.

Incident Details

All incident changes saved.

Required to save: Case Title and Scenario Name.

Incident: n/a

Case Title

Scenario Name

Case Number

Date

Planner

Datum Number

Search Plan (A/B/C)

Search/Drift Objects

No objects selected

Scenario Notes

Current Wx Reports

Quick links for recorded local wind and current report overlays.

Quick Review

All wizard step screens (Scenario through Display) open in modal quick review.

Worksheet Review

Original worksheet section tabs plus Parameter Abbreviations and All/Collapse controls.

Core SAR Terms

PIW — Person in Water
LKP — Last Known Position
EIP — Estimated Initial Position
PD — Probable Datum
DATUM — Most probable search position
TC — Tidal Current
SC — Sea Current
WC — Wind Current
OWC — Other Water Current
TWC — Total Water Current
LEEWAY — Wind-driven drift component
ZTA — Total Available Search Effort
Fs — Optimal Search Factor
SRU — Search and Rescue Unit
A/O — Area of uncertainty

Error / Worksheet Terms

ASWe — ASW probable error
ASWDVe — ASW drift velocity error
TCe — Tidal current error
SCe — Sea current error
WCe — Wind current error
OWCe — Other water current error
TWCe — Total water current error
LWe / LWE — Leeway error
DVe — Drift velocity error
De — Drift error distance
E — Total probable error
E² — Squared total probable error
fW / fV / ff — Search effort correction factors
Wu — Corrected sweep width
Z — Search effort total
Zta — Total available effort over time

OpenDrift / Particle Type Codes

Official OpenDrift Leeway keys from OBJECTPROP.DAT are loaded into the Particle Type picker.

PIW-1 — Person in water (mean values)
LIFE-RAFT-NB-1 — Life-raft, no ballast (mean values)
LIFE-RAFT-DB-10 — Life-raft, deep ballast (mean values)
SKIFF-1 — Skiff / runabout powerboat
SAILBOAT-1 — Sailboat mono-hull (average)
FISHING-VESSEL-1 — Fishing vessel (mean values)

6. Generate Models

Step 6.1 Model Selection and Run Controls

Use this section to select one or more active models and run validation/submit actions. The layout supports additional models as they are enabled.

Model Selection

Selected models (2): IAMSAR, OpenDrift

Available Models

IAMSAR ON OpenDrift ON

Planned / Future Models

CANSARP

Instructions placeholder for future guidance.

Step 6.2 Shared Drift Inputs (all selected models)

Start Lat * Start Lon * Hours * dt (min) *

Set Dir (deg True) * Set Speed (kn) * Wind Dir (deg True) * Wind Speed (##.#kts) *

Wind Direction Convention

Leeway Coeff * Uncertainty (kn) *

Leeway Figure (active object) Leeway Speed (graph) (kts) Leeway Divergence (graph) (deg) Leeway Error LWe (graph) (kts)

Selected Object Transfer (Leeway to Generate Models)

Object	OBJKEY	Figure	Leeway Speed (kts)	Divergence (deg)	LWe (kts)
Waiting for Leeway object selection...

Step 6.3 IAMSAR Model Settings

No additional IAMSAR-only controls are required here. IAMSAR uses the shared inputs from Step 6.2.

OpenDrift Model Configuration (Steps 6.4-6.6)

Step 6.4 OpenDrift Core Settings

OpenDrift Model *

No model selected

Select one or more models. Availability is validated against backend health at startup.

Particles * Time Step (sec) *

Step 6.5 OpenDrift Advanced Tuning

Seed Radius (m) Random Seed (optional) Particle Type (OpenDrift OBJKEY) Selected object profile key(s) will be shown here in readable form.

Step 6.6 OpenDrift Reader Data Sources (system-managed)

OpenDrift readers are loaded from system settings when configured. Reader URLs are sourced from Admin system settings and are not editable here.

Active OpenDrift Readers (System Settings) Loading

Last loaded: pending

Reader	Kind	Provider	Coverage	State	Source URL
Loading OpenDrift reader settings...

Run History

Selected: 0

1. Sources

Current Source Wind Source Confidence (0-1)

Current Forecast Provider Wind Forecast Provider

Source Timestamp (UTC) Notes

2. Marine Datum Summary

A. Starting Position For This Drift Interval

1. Type of Position LKPLast Known EIPEstimated Incident PDPrevious Datum

1.A LKP Drift Direction

Position Time (UTC, HHMMZ) Position Date

3. Latitude of Position Latitude Hemisphere Longitude of Position Longitude Hemisphere

Edit rules: Latitude must use DD-MM.M with N/S. Longitude must use DDD-MM.M with E/W. For western hemisphere incidents, use longitude hemisphere W.

Auto determine location assessment type from position Location Assessment Type (calculated) Distance to Shore (nm, estimated)

If distance to shore is greater than 6nm, assessment is Oceanic; otherwise Coastal. Disable auto to manually override from dropdown. Note: OpenDrift external readers are separate from shoreline distance providers. Configure shoreline distance under drift.service.runtime.location_assessment.providers.

B. Datum Time

Commence Search Time (UTC, HHMMZ) Commence Search Date

Time to Datum (hours) Additional Forecast Beyond Datum (hours) Total Forecast Window (hours) 2.B.4 Drift Beyond Timeline

C. Average Surface Winds (ASW)

C.1 ASW Direction C.2 ASW Speed C.3 ASW Total Hours C.4 Probable Error of the Average Surface Wind (ASWe, kts) C.5 Probable Error of Drift Velocity due to ASW (ASWDVe, kts)

D. Total Water Current (TWC)

2.D.1 Total Water Current (TWC) Set (T°) 2.D.1 Total Water Current (TWC) Speed (kts)

2.D.2 Probable Total Water Current Error (TWCe) (kts)

E. Leeway (LW)

2.E.1 LEFT of Downwind Set (T°) 2.E.1 LEFT of Downwind Speed (kts)

2.E.2 RIGHT of Downwind Set (T°) 2.E.2 RIGHT of Downwind Speed (kts)

2.E.3 Probable Leeway Error (LWe) (kts)

F. Total Drift (TD)

Use a manoeuvring board or calculator to add Total Water Current and Leeway vectors.

2.F.1 Drift Directions LEFT (T°) 2.F.1 Drift Directions RIGHT (T°)

2.F.2 Drift Speed LEFT (kts) 2.F.2 Drift Speed RIGHT (kts)

2.F.3 Drift Distance LEFT (line F.2 x line B.2) (NM) 2.F.3 Drift Distance RIGHT (line F.2 x line B.2) (NM)

2.F.4 Total Probable Drift Velocity Error (DVe) (kts) $DVe = \sqrt{ASWDVe^2 + TWCe^2 + LWe^2}$

G. Datum Positions and Divergence Distance

Using a chart, universal plotting sheet or calculator, determine the datum positions and divergence distance (DD).

Coordinate format for G fields: Latitude DD-MM.M and Longitude DDD-MM.M (decimal minutes).

2.G.1 Latitude (left of downwind, DD-MM.M) Hemisphere (N/S) Longitude (left of downwind, DDD-MM.M) Hemisphere (W/E)

2.G.2 Latitude (right of downwind, DD-MM.M) Hemisphere (N/S) Longitude (right of downwind, DDD-MM.M) Hemisphere (W/E)

2.G.3 Divergence Distance (DD) (NM)

H. Total Probable Error of Position (E) and Separation Ratio (SR)

Attach Total Probable Error of Position (E) worksheet.

2.H.1 Total Probable Error of Position Squared (E²) (NM²) Calculated in Total Error worksheet line D.1.

2.H.2 Total Probable Error of Position (E) (NM) Calculated in Total Error worksheet line D.2.

2.H.3 Separation Ratio (SR = DD/E) $SR = DD / E$

3. Total Water Current

A. Observed Total Water Current (TWC)

Observed TWC Source Observed TWC Dir (deg True) Observed TWC Speed (kts) Observed TWC Error TWCe (kts)

For directional entries, use true direction in degrees (0-359).

B. Computed Total Water Current

1. Tidal Current (TC)

TC Source TC Dir (deg True) TC Speed (kts) TC Error TCe (kts)

Calculated fields: TC Source, TC Dir, and TC Speed are auto-derived from current source mode + Tidal Current Data modal rows.

2. Sea Current (SC)

SC Source SC Dir (deg True) SC Speed (kts) SC Error SCe (kts)

3. Wind Current (WC)

Manual override for B.3 values (auto is default)

ASW Direction (from Datum C.1, deg True) ASW Speed (from Datum C.1, kts) Downwind Direction (ASW direction +/- 180, deg True)

Wind Drift from Figure N-1 (kts) Divergence of Wind Current (deg) Wind Set Direction (Downwind + Divergence, deg True) WC Speed (kts)

Probable Error of Wind Current (WCe, kts)

Show N-1 WC graph Show N-1 reference image

IAMSAR Appendix N-1 reference — N-1 Reference Image

4. Other Water Current (OWC)

OWC Source OWC Dir (deg True) OWC Speed (kts) OWC Error OWCe (kts)

5. Computed Total Water Current (TWC) Set/Drift

Computed TWC Set (deg True) Vector direction from combined TC, SC, WC, and OWC components. Computed TWC Drift (kts) Vector magnitude from combined TC, SC, WC, and OWC components.

6. Computed Probable Total Water Current Error (TWCe)

Computed TWCe (kts) $TWCe = \sqrt{TCe^2 + SCe^2 + WCe^2 + OWCe^2}$

5. Total Error (E)

A. Probable Distress Incident / Initial Position Error (X)

Use line A.6 when this drift interval starts from a distress position; enter A.6 override from previous datum when applicable.

A.1 Navigational Fix Error (NM) Entered value (from table N-1 or N-2). A.2 Dead Reckoning (DR) Error Rate (%) Entered value (from table N-3). A.3 DR Distance Since Last Fix (NM) Entered value. A.4 DR Navigational Error (A.2 x A.3) (NM) $A.4 = A.2 \times A.3$

A.5 Glide Distance (NM) Entered value (if aircraft/parachute descent heading is unknown). A.6 Probable Initial Position Error X (NM) $X = A.1 + A.4 + A.5$ (or previous datum override below)

A.6 Override from previous datum H.2 (NM) If this interval starts from a previous datum, enter previous worksheet H.2 here.

B. Total Probable Drift Error (De)

B.1 and B.2 are calculated inputs; B.3 is computed automatically.

B.1 Total Forecast Window (hours) B.2 Probable Drift Velocity Error (DVe) (kts) B.3 Total Probable Drift Error De (NM)

Leeway Error (LWe) (kts)

C. Probable Search Facility Position Error (Y)

Enter C.1-C.3 manually; C.4 and C.5 are calculated automatically.

C.1 Navigational Fix Error (NM) C.2 Dead Reckoning (DR) Error Rate (%) C.3 DR Distance Since Last Fix (NM) C.4 DR Navigational Error (C.2 x C.3) (NM)

C.5 Probable Search Facility Position Error Y (NM)

D. Total Probable Error of Position (E)

D.1 and D.2 are calculated from X, De, and Y.

D.1 Sum of Squared Errors (NM²) D.2 Total Probable Error of Position (NM)

Leeway Divergence Angle (deg) Entered value or populated from Leeway graph selection.

4. Leeway Graphs

Auto Calcs from Graph

Auto mode ON: LWe and Leeway Divergence are graph-linked, read-only, and highlighted in blue.

Leeway Profiles Per Selected Object

Paradigm: use one tab per selected drift object. Active tab values feed per-object run payload coefficients and drive the interactive graph/reference focus.

Average Surface Wind (ASW) Direction (deg T) Average Surface Wind (ASW) Speed (kts)

Downwind Direction (ASW direction +/- 180 deg) (deg T)

Leeway Speed (from figure N-2 or N-3 below) (kts) From Graph Leeway Divergence Angle (from figure N-2 or N-3 below) (+/- deg) From Graph

Left of downwind (deg T) Right of downwind (deg T)

Left of downwind Direction (deg T) Left of downwind Speed (kts) Right of downwind Direction (deg T) Right of downwind Speed (kts)

Probable Leeway Error (LWe) (from figure N-2 or N-3) (kts) From Graph

Show appendix graph templates and overlays Show reference images below graphs Auto-focus active object on tab switch Line Scope

Transparency is enabled in all scopes, including Selected object only, via Search Object opacity sliders.

Search object sliders: loading...

N-2: Leeway of liferafts, survival craft and PIWs

N-3: Leeway rates for various craft

Red dot: Leeway speed at ASW. Blue dot (N-2): Wind current drift point at ASW.

IAMSAR Appendix N-2 reference — N-2 Reference Image

IAMSAR Appendix N-3 reference — N-3 Reference Image

Active object: n/a

7. Effort Allocation Worksheet (Zta)

Datum Type Datum Line Length L (NM) Optimal Search Factor fs Nearest Assignable S (comma list, NM)

8. SRU / Zta Data

Total Available Search Effort (Zta NM²)

Current Records Wind Records

Speed Loop Auto-pan Pan Mode N

No timeline Distance: n/a

Show center track

Style key: Center track = solid faded, Left divergence = dotted, Right divergence = dashed.

Administration: Users

Affiliation Scope

Company Entity Location Entity Address

User Management

Users Overview

Use this section for user profiles, roles, activation, and organization affiliation.

Guidance

Use one record per application/service. Suggested names: web.app and drift.service. Keep settings practical: user-facing defaults, runtime/performance limits, database pool tuning values, and location-assessment distance thresholds.

System Settings

New Setting Template

Template Base New App Name

Editor Controls

Setting ID (blank=create) Application Name Schema

Choose a setting and load schema controls. Grouped editable entries are shown in the right column.

Loaded Setting Entries

Load a schema to view grouped editable setting entries.

No schema loaded.

Settings JSON (View and Raw)

JSON Subcategory

(not set)
PIW (Unknown)
PIW (Conscious/PFD)
PIW (Survival suit)
PIW (Scuba suit)
PIW (Vertical)
Life Raft
Life Raft (Deep ballast)
Life Raft (Shallow ballast)
Small Open Boat
Sport Boat (cuddy cabin)
Sport Fisher (center console)
Sailing Vessel
Sailing Vessel (Full keel)
Skiff (Flat-bottom)
Skiff (V-hull)
Fishing Vessel
Commercial Fishing Vessel
Coastal Freighter
Kayak
Surfboard with Person
EPIRB/SLDMB
FV Debris
Other

User	—
Company	Orange Force Marine Ltd. / IAMSARSolutions
App Version	—
Build Date/Time	—
Environment	—

Sign in to Drift Modelling

Password Update Required

Drift Parameters

Incident Details

Current Wx Reports

Quick Review

Worksheet Review

Core SAR Terms

Error / Worksheet Terms

OpenDrift / Particle Type Codes

6. Generate Models

Step 6.1 Model Selection and Run Controls

Step 6.2 Shared Drift Inputs (all selected models)

Selected Object Transfer (Leeway to Generate Models)

Step 6.3 IAMSAR Model Settings

OpenDrift Model Configuration (Steps 6.4-6.6)

Step 6.4 OpenDrift Core Settings

Step 6.5 OpenDrift Advanced Tuning

Step 6.6 OpenDrift Reader Data Sources (system-managed)

Active OpenDrift Readers (System Settings) Loading

Run History

1. Sources

2. Marine Datum Summary

A. Starting Position For This Drift Interval

B. Datum Time

C. Average Surface Winds (ASW)

D. Total Water Current (TWC)

E. Leeway (LW)

F. Total Drift (TD)

G. Datum Positions and Divergence Distance

H. Total Probable Error of Position (E) and Separation Ratio (SR)

3. Total Water Current

A. Observed Total Water Current (TWC)

B. Computed Total Water Current

1. Tidal Current (TC)

2. Sea Current (SC)

3. Wind Current (WC)

4. Other Water Current (OWC)

5. Computed Total Water Current (TWC) Set/Drift

6. Computed Probable Total Water Current Error (TWCe)

5. Total Error (E)

A. Probable Distress Incident / Initial Position Error (X)

B. Total Probable Drift Error (De)

C. Probable Search Facility Position Error (Y)

D. Total Probable Error of Position (E)

4. Leeway Graphs

Leeway Profiles Per Selected Object

7. Effort Allocation Worksheet (Zta)

8. SRU / Zta Data

Consultant

Trainer Console

All Run History

Training Incident Management

Template Library

Saved Training Incidents

User Settings

Display Preferences

Profile

Password

Administration: Users

Affiliation Scope

Users

User Management

Users Overview

Reports

Summary

Affiliations

User Affiliation

Notes

Companies

Company

Notes

Entities

Entity

Notes

Addresses

Address

Notes

Classes

Class