# SWO Radian Rule — Streamline your UNREP approach

> Naval UNREP conning officer's tool for automated radian rule calculations. (iPhone/iPad app by Corey McCollum.)

- Source: https://appshunter.io/ios/app/swo-radian-rule/id1672149451 (this page in markdown: same URL + `.md`)
- Developer: [Corey McCollum](https://appshunter.io/developer/1672149453)
- Category: Navigation, Utilities
- Price: $0.99
- Rating: 5.00/5 from 2 App Store ratings · 1 written reviews indexed
- Age rating: 4+
- Requires: iOS 16.2 · 6 MB
- Languages: English
- Released: 2023-02-18
- Data updated: 2026-06-01
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/swo-radian-rule/id1672149451/reviews.md

## What is SWO Radian Rule?

Are you the Conning Officer assigned to make the approach for an UNREP? Do you struggle doing "public math" with the radian rule, especially under pressure? Have you been relying upon a paper cheat sheet and wish you had an app to automate the radian rule and provide you instant results? Then SWO Radian Rule is the answer to your prayers!

Designed from the ground up with the Conning Officer in mind, SWO Radian Rule provides an intuitive, user-friendly interface that clearly displays all of the critical information you need at a glance. Simply dial-in the appropriate Degrees Offset and Range to Guide, and SWO Radian Rule will do the rest, instantly calculating estimated Separation Alongside, target Degrees Offset, and your target Bearing to Guide. SWO Radian Rule allows you to select on which side of your ship the Guide will be (PORT or STBD), R Corpen, and target Separation Alongside. And, SWO Radian Rule is compatible with Darken Ship requirements, just in case you're conducting a night time UNREP.

Whether you're a brand new Ensign or a salty ol' Senior Officer, SWO Radian Rule is an invaluable tool that you'll wish you had sooner. Make a seamless approach on the Guide every time with the help of SWO Radian Rule!

## Key features

- Automated radian rule calculations
- Instant results for key metrics
- Intuitive user interface
- Supports PORT or STBD guide placement
- Compatible with Darken Ship requirements
- Calculates Separation Alongside, Target Degrees Offset, and Target Bearing to Guide

## Recent user reviews (1 of 1)

All indexed reviews: https://appshunter.io/ios/app/swo-radian-rule/id1672149451/reviews.md

### 5/5 — Finally!!!

*2023-02-18*

OMG! Where was this app when I was an Ensign?! This will make life SO MUCH easier when we do UNREP approaches! I'm glad someone FINALLY took the time to make something like this. Best $0.99 I've spent today!

## Frequently asked questions about SWO Radian Rule

### What is SWO Radian Rule used for?

SWO Radian Rule is a navigation tool designed to automate complex radian rule calculations for naval underway replenishments (UNREP). It helps conning officers determine critical metrics like separation alongside and target bearing to guide, simplifying the approach process.

### How much does SWO Radian Rule cost?

SWO Radian Rule is a paid application, available for $0.99. This one-time purchase grants you access to its full functionality for streamlining UNREP approaches.

### What devices is SWO Radian Rule compatible with?

Currently, SWO Radian Rule is supported on iPhones. Future updates may expand compatibility to other devices.

### How often is SWO Radian Rule updated?

The app was last updated on August 20, 2024, indicating active development and support. This suggests regular improvements and bug fixes are likely.

### What is the age rating for SWO Radian Rule?

SWO Radian Rule has an age rating of 4+, making it suitable for a wide range of users. This rating typically indicates content that is generally safe for all ages.

### Does SWO Radian Rule have ads?

No, SWO Radian Rule does not contain advertisements. As a paid application, it offers an ad-free experience for its users.

### What user feedback is available for SWO Radian Rule?

SWO Radian Rule has received a perfect 5.0-star rating from 2 reviews. This indicates a highly positive user sentiment among its current user base.

### Can SWO Radian Rule be used for night UNREP operations?

Yes, SWO Radian Rule is compatible with Darken Ship requirements, making it suitable for conducting night time UNREP operations. This feature ensures its utility in various operational conditions.

## Version history (last 3 releases)

### 1.1.0 — 2024-08-20

- Enabled a feature if the calculated distance separation alongside is less than the target distance separation alongside, then the calculated distance separation alongside value will "bounce" in RED font to gain the attention of the Conning Officer.
- Minor updates to app esthetics.
- Update to author biography.

### 1.0.24 — 2023-02-26

- Minor esthetic updates to the main display artwork and appearance.

### 1.0.23 — 2023-02-18

No release notes.

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## More apps by Corey McCollum

- [Cube-O-Pedia](https://appshunter.io/ios/app/cube-o-pedia/id6471312947)

All apps by Corey McCollum: https://appshunter.io/developer/1672149453

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-01.*