Our first endeavour into the world of active control. Project Aptos aims to develop an aerodynamic vertical active stabilisation system for future sounding rockets.

Render of the Pathfinder rockets couplets

Being run as a Masters level team project, Aptos uses a set of actively controlled canards to manipulate the orientation of the rocket.

This technology will allow our future rockets to maintain a more vertical trajectory during flight, and flying vertically means flying higher. Additionally, we should have less dispersion.

Technical drawings of the Pathfinder rocket

A new rocket was developed as part of this project – Pathfinder.

This vehicle acts as a test-bed for future active control flights, allowing us to rapidly prototype and test new designs.


Project Timeline

October 2022
October 2022

Started Project

November 2022
November 2022

Preliminary Design Review

February 2023
February 2023

Critical Design Review

October 2023
October 2023

New Hardware and Firmware

April 2024
April 2024

Active Control Test Flight

The first iteration of the Aptos control module was developed over the course of just eight months. During this time, the Pathfinder rocket was designed and built alongside the module.

The first Pathfinder testing campaign took place in April 2023 from the SARA launch site, in Fairlie Moor. Despite not having the controller enabled, the team has gained value knowledge and data. The summary of the weekend can be view here:

A new team of five designed a new Flight Computer based on an STM32 chip and developed custom bare metal C firmware from the ground up. The integration of the previously design controller was improved and the first steps towards a custom Telemetry board were made.

After five months of improvement, the Aptos group were able to launch Pathfinder again, this time from Midlands Rocketry Club, with the active controller enabled. There is on going process to analyse the data gathered during the flight, but the results are positive.



Pathfinder is a simple, single-ejection, low altitude rocket. Its nose cone, body tubes, coupler, and fins are all fibreglass. The fincan is mounted on bearings, to allow the rear fins to spin relative to the rocket. This prevents the deflected wake from the canards from causing the rocket to roll during flight.


1.92 m


0.10 m

Total mass:

6.9 kg

Target apogee:

~ 880 m (2,890 ft)

Project Aptos is the first step towards developing actively controlled rockets.

The Pathfinder results and documentation will be released on this page in June 2024.