Leeds
Doncaster
Sheffield
Bradford
Hull
Halifax
Sunderland
Newcastle
Middlesborough
Yorkshire Moors
Teesside
Cumbria
Harrogate
Teesdale
York
Yorkshire Dales
Northumberland
Goole
Carlisle
Keswick
Kendal
Barrow-in-Furness
Lancaster
Blackpool
Morecambe
Southport
Liverpool
Wigan
Manchester
Blackburn
Burnley
Forest of Bowland
Oldham
Chester
Stockport
Peak District
Skipton
Crewe
Rotherham
Stoke
Driffield
When it comes to surveying, we believe in doing things properly, accurately, efficiently, and with as little fuss as possible. That’s why we’re always on the lookout for advanced equipment to keep ahead of the game and consistently upgrade our performance.
With thanks to Tri-Site, we were introduced to the Apache 4 from CHC Navigation – a powerful, portable hydrographic surveying vessel to add to our arsenal at Tri-Tech and Site Surveying Services.
What is the Apache 4?
In short: it’s an unmanned surface vessel (USV) designed to carry out detailed hydrographic surveys in places that are tricky, or dangerous, for humans to go. Think rivers, reservoirs, ports, and lakes. Easy to transport, it’s packed with smart tech like dual GNSS and IMU integration, single or multibeam echo sounders, and autonomous navigation.
For our team, that means one thing: more data, less drama.
Survey Smarter Not Harder
The Apache 4 isn’t just another USV. It’s a data-driven workhorse designed for high-accuracy hydrographic and bathymetric surveys, even in difficult or obstructed environments.
Here are a few key features we love—and why they matter to our clients:
Autonomous Navigation with Adaptive Water Flow Tracking
Thanks to a GNSS + IMU positioning system, the Apache 4 stays on course even in turbulent flow or when GPS signals are limited. This means highly accurate cross-sectional data, especially important for flood modelling and riverbed profiling.
Hover Technology for Pinpoint Measurements
At the start and end of ADCP observations, the vessel can hover steadily in place—reducing noise in flow estimations and increasing data reliability.
Integrated Single Beam Echo Sounder
With depth range capabilities from 0.15 to 200 meters and ±0.01 m accuracy, this unit provides detailed water depth profiles and can verify or complement ADCP tracking data.
Compact Yet Capable
Don’t let its size fool you: this vessel can carry up to 35 kg of payload, including ADCP sensors, multibeam echo sounders, side scan sonar, and water quality monitors.
Battery Life Built for the Field
With up to 8 hours of endurance on a single charge and hot swappable batteries, our team can complete large surveys in one go -no mid-mission swaps or delays.
Smart Control, Real-Time Feedback
Using CHC’s dedicated Easysail app and Android control system, we plan missions, view live video of the area with built-in 360 camera, data feeds, and make real-time adjustments -all from shore.
Obstacle Avoidance and Safety First
With millimeter-wave obstacle detection, auto-return on low battery or lost signal, and a triple-hull carbon fiber design (IP67 rated), safety and reliability are built into every survey.
How We’re Using it On-site
At both Tri-Tech and Site Surveying Services, we’re known for combining experience with innovation—and the Apache 4 is a natural extension of that philosophy.
We’ve already put it to work on:
- Flood modelling projects, where it’s helped us safely capture accurate waterbed data without sending people into unstable terrain.
- Dredging surveys, providing before-and-after comparisons for clients needing to keep waterways navigable.
- Reservoir inspections, allowing us to cover large, isolated areas in record time.
- Environmental monitoring, collecting data in sensitive ecosystems where minimising human disruption is essential.
Instead of sending out a full team with a boat, we can now deploy the Apache 4 with minimal site operatives – cutting down time, risk and costs. It navigates survey routes autonomously, streams data in real-time, and slots straight into our existing data workflows. It’s fast, it’s efficient, and most importantly -it’s reliable.
Why This Matters to Our Clients
We know that when you partner with us, you’re putting trust in our hands. That’s why we don’t just chase the latest gadgets, we invest in equipment that genuinely improves the way we deliver results. The Apache 4 lets us capture high-quality hydrographic data quickly, safely, and with minimal disruption to the surrounding environment.
It’s just one more way we’re keeping your projects on track, on time, and built on solid, accurate foundations.
A Final Word From the Team
Surveying is the backbone of everything within the built environment, from infrastructure and construction to environmental protection. At Tri-Tech and Site Surveying Services, we’re proud to play a part in shaping that foundation, bringing together modern technology, proven expertise, and a service you can truly rely on.
If you’re curious about how the Apache 4 could support your next project, we’re always here for a chat!
