Most efficient fibre-optic deployment system

 First jet-propelled fibre-optic system with 25,000-ft deployment in less than an hour 

WellSense, a specialist in fibre optic well diagnostics, has developed a ground breaking, single-use, jet-propelled and battery powered well conveyance technology, which is able to rapidly deploy bare fibre into highly deviated wells. The conveyance system has been designed to improve the speed, quality, cost and efficiency of diagnostic surveys in horizontal wells. FliCS uses magnetic launch, battery power and jet-drive thrust to deploy fibre for real-time temperature, strain and acoustic sensing. The conveyance system has been designed to improve the speed, quality, cost and efficiency of diagnostic surveys in horizontal wells. AUK company has successfully tested an advanced diagnostic technology in the US that offers faster, safer and more efficient fibre-optic deployment.

WellSense’s Fibre Line Intervention Conveyance System (FliCS) uses jet propulsion and battery power to deploy bare fibre rapidly into complex, highly deviated wells. Tested in the Permian Basin in August 2025, the system delivered a 25,000-ft Fli probe into a 19,000-ft horizontal well about ten times faster than conventional pump-down methods. WellSense successfully completed a technology field trial, where the FiberLine Intervention Conveyance System (FliCS) deployed bare fibre into a 19,000 foot uncompleted well in the Permian Basin for cross well strain monitoring. The deployment took just 50 minutes. The trial was delivered for a major international operator which provided support for early technology development and, witnessing the results, the operator has confirmed its intention to redeploy the technology in four further projects over the next three months.

“FliCS will provide well operators a cost-effective, low-risk well surveillance solution for horizontal wells for the first time,” said Annabel Green, CEO at WellSense. Earlier, Penn State researchers proposed storing renewable energy in depleted oil and gas wells using compressed air, reducing costs and addressing environmental concerns about abandoned wells. FliCS has been developed at WellSense’s UK headquarters and R&D hub in Aberdeen, by Dan Purkis, the company’s founder, technology director and respected industry innovator. The new well access solution introduces the ability to deploy Fli into horizontal wells to acquire distributed acoustic sensing and distributed temperature sensing data across the reservoir. FliCS is a jet-propelled, battery-powered platform representing a major advance in fibre-optic well diagnostics. The lightweight conveyance system is designed to rapidly deploy bare optical fibre into complex, highly deviated or horizontal wells without requiring conventional pump-down or tractor-assisted operations. FliCS is triggered by a magnetic switch and powered by small on-board batteries at launch. Its jet-drive propulsion system, when deployed, creates thrust by accelerating well fluids via an impeller unit, which moves the probe through the wellbore.

Annabel Green, CEO at WellSense, said, FliCS will provide well operators a cost-effective, low risk well surveillance solution for horizontal wells for the first time. While it will have many applications in well integrity, it also enables a major expansion of injection profiling capabilities. This has global application, providing performance data to enable water injection to be optimised for effective pressure support and oil displacement. The apparatus de-spools optical fibre as it travels, allowing high-resolution distributed fibre-optic sensing (DFOS) to monitor temperature, strain and acoustic data in real time along the well’s length. The prototype machine showed remarkable speed, deploying up to 25,000 feet of fibre in little over an hour, which is around 10 times quicker than the average of 35 feet per minute for traditional tractor conveyance methods. FliCS uses less fluid and operates at about 350 feet/ minute, drastically reducing operating time and expense.

In addition to speed and efficiency, FliCS enhances safety and operational flexibility. The system’s lightweight, non-metallic components pose negligible risk to future well interventions, as they can be left safely in the toe of the well or pushed to the bottom if retrieval is unnecessary. “While it will have many applications in well integrity, it also enables a major expansion of injection profiling capabilities. This has global application, providing performance data to optimize water injection for effective pressure support and oil displacement,” said Green. “For our key clients in the Middle East, FliCS will provide valuable diagnostics for matrix acid stimulation. This approach is widely used to improve carbonate rock matrix permeability and flow channels, so improved knowledge of fluid placement can greatly enhance treatment and directly improve well performance.

Wellsense highlights that its Fli solutions are designed for versatility, supporting a broad spectrum of well applications such as production optimization, well integrity evaluation, stimulation monitoring and abandonment planning. The Fli Dynamic De-Spool can be deployed into live wells without the need for a rig or heavy intervention systems, significantly reducing operational complexity and cost. Their low-impact deployment method suits them particularly for remote and environmentally sensitive sites, where conventional intervention equipment may be impractical or disruptive. The probe is lowered manually or through a simple hydraulic release mechanism, allowing for rapid mobilization and minimal interference with on-going operations. “We’re incredibly excited by the market growth opportunity this unique solution presents for us, and by the efficiency, diagnostic and carbon reduction benefits it’s set to provide the wider industry. Our next step is to deliver our first, multi-unit, prototype order while developing a slimmer model for deployment through smaller tubing. We’ll be maturing the technology ready for commercial launch early next year but actively engaging with customers at ADIPEC and beyond to discuss opportunities” said Green. 

In practical deployment, the system’s simplicity enables a single engineer to complete the entire process in under an hour. Data acquisition begins immediately once the fibre enters the well, ensuring real-time insights into well performance. Depending on the depth and conditions of the well, most surveys are completed within a single shift. According to the firm, the streamlined approach enhances efficiency, reduces downtime, and delivers high-quality data faster, making Fli Technology an ideal solution for operators seeking safe, reliable and cost-effective well monitoring and diagnostic capabilities across various environments. The pioneering FliCS conveyance system from WellSense uses lightweight battery powered jet propulsion which is triggered by a magnetic switch at launch. Jet-drive technology accelerates well fluids through an impellor sub to generate thrust while the probe de-spools optical fibre along the well to enable highly sensitive distributed fibre optic sensing data to be acquired. The prototype model deploys 25,000 feet of fibre in little over an hour, travelling around 350 ft/ min. versus ~35 ft./ min. for a conventional tractor conveyance. The risk to future operations is negligible as the lightweight components can be left in the toe of the well or pushed to the bottom.