20 April 2026

Helix Exploration PLC

("Helix Exploration" or "Helix" or the "Company")

Helix selected by Chimaera Fund for Strategic Partnership with US Air Force

Helix Exploration PLC (AIM: HEX, OTCQB: HEXFF), the helium exploration and development company advancing the Rudyard Helium Project ("Rudyard") in northern Montana, is pleased to announce that it has been selected by Renaissance Philanthropy's Chimaera Fund to participate in the Air Force Geologic Hydrogen Energy Resilience Initiative, a demonstration programme assessing whether geologic hydrogen can strengthen energy resilience at critical Air Force Bases ("AFB").

Highlights

•     Congressional Mandate: In support of a Congressional mandate requiring the Department of War to achieve 99.9% energy availability at critical military installations by 2030, Renaissance Philanthropy's Chimaera Fund has launched a demonstration programme to explore whether geologic hydrogen could contribute to energy resilience at AFBs.

•     Competitive Selection: Helix was selected from nearly 30 respondents to a Request for Information ("RFI") issued by the Chimaera Fund, which attracted responses from exploration companies, national laboratories, university research groups, sensing and detection firms, and engineering consultancy firms.

•     Active Partnership: Helix will work collaboratively with the Chimaera Fund, contributing subsurface data, drilling cost data, and geological expertise from its active Rudyard programme to a techno-economic assessment of geologic hydrogen potential near Malmstrom AFB and other targeted installations. Helix will receive funding from the Chimaera Fund to support its contribution.

•     Proximity: The Company's Rudyard project is located approximately 120 miles from Malmstrom AFB, home to the 341st Missile Wing and one of only three U.S. Air Force installations operating the Minuteman III intercontinental ballistic missile system.

•     Geological Indicators: As announced on 16 October 2025, the Company's deep well programme at Rudyard confirmed the presence of key geological indicators for hydrogen generation, encountered during active helium exploration. Helix is preparing additional coring and laboratory analysis to further characterise the resource.

•     Strategic Validation: The partnership validates the strategic value of the Company's geological assets beyond helium, demonstrating direct applicability to national energy security priorities.

Details of the Partnership

The Chimaera Fund at Renaissance Philanthropy issued an RFI to identify partners with existing well infrastructure, hydrogen-related subsurface data, and active exploration programmes near key AFBs. The RFI attracted nearly 30 responses from across the geologic hydrogen ecosystem. Following evaluation, a small number of commercial partners were selected to serve as primary performers for a small-scale demonstration.

Helix was selected on the basis of its active helium exploration programme in north-central Montana, during which the Company encountered a highly favourable geological hydrogen deposit at Rudyard. As a core partner, Helix will work alongside the Chimaera Fund contributing subsurface measurements, drilling cost data, mineralogical and geochemical analysis, and well infrastructure data from active field operations near Malmstrom AFB. The results of the programme will inform a techno-economic assessment of geologic hydrogen potential near targeted installations.

The official announcement can be found at https://www.renaissancephilanthropy.org/insights/chimaera-partner-selection

Strategic Significance

Malmstrom AFB, located near Great Falls, Montana, is home to the 341st Missile Wing, one of only three U.S. Air Force Global Strike Command wings operating the LGM-30G Minuteman III intercontinental ballistic missile system. Domestically sourced energy supply near such installations is a matter of national security. The proximity of the Company's Rudyard project to Malmstrom, combined with the hydrogen-generating geological indicators already confirmed, positions Helix as a uniquely relevant participant in this initiative.

Bo Sears, Chief Executive Officer, Helix Exploration PLC

"The selection of Helix in this pioneering research initiative reinforces the significance of the geological indicators we have identified at Rudyard and the potential they hold for geologic hydrogen. We are genuinely excited to be working alongside the U.S. Air Force and the Chimaera Fund as partners in this effort - not simply as data providers, but as active collaborators bringing subsurface expertise and field operations to bear on a shared objective. The convergence of national energy security priorities with our existing geological assets at Rudyard represents exactly the kind of opportunity we have been building toward, and we look forward to advancing this work together."

 Keith Spickelmier, Chairman, Helix Exploration PLC

"We are honoured to be able to announce our participation in the Geologic Hydrogen Energy Resilience Initiative alongside the Chimaera Fund & the US Airforce. I would like to commend our team for solidifying this relationship and we are optimistic about the potential of this partnership going forward."

Background: Geologic Hydrogen

Geologic hydrogen, also referred to as natural or "gold" hydrogen, is hydrogen generated through natural subsurface processes including serpentinization of iron-rich minerals, radiolysis of water by radioactive decay, and deep crustal degassing. Unlike manufactured hydrogen, it requires no energy input for production, no water consumption, and produces no carbon emissions. The U.S. Department of Energy has identified geologic hydrogen as a potentially transformative domestic energy resource.

This announcement contains inside information for the purposes of the UK Market Abuse Regulation, and the Directors of the Company are responsible for the release of this announcement.

Enquiries

Helix Exploration

Cairn - Nominated Adviser

Hannam & Partners Brokers

Camarco - Financial PR

Notes to Editors

Helix Exploration is a helium exploration company focused on the exploration and development of helium deposits within the 'Montana Helium Fairway'. Founded by industry experts with extensive experience of helium systems in the US, the Company listed in April 2024.

Helix is focused on production at its Rudyard Project in northern Montana, taking advantage of existing infrastructure and low-cost processing. The Company has four production wells targeting up to 236ft Helium / Nitrogen gas in the Souris and Red River formations, flowing up to 3,800 Mcf/day at 1.2% helium. Rudyard field can support multiple production wells and has potential to generate net revenue of $115 - $220 million over a 12.5 year life of field.

Helix is committed to open and transparent communication with investors and the wider market as the project progresses through development into production.

"Our approach is simple: build scale efficiently, develop resources strategically, and deliver near-term cash flow." CEO - Bo Sears

The Company's Admission Document, and other information required pursuant to AIM Rule 26, is available on the Company's website at https://www.helixexploration.com/.

Caution regarding forward looking statements

Certain statements in this announcement, are, or may be deemed to be, forward looking statements. Forward looking statements are identified by their use of terms and phrases such as ''believe'', ''could'', "should" ''envisage'', ''estimate'', ''intend'', ''may'', ''plan'', ''potentially'', "expect", ''will'' or the negative of those, variations or comparable expressions, including references to assumptions. These forward-looking statements are not based on historical facts but rather on the Directors' current expectations and assumptions regarding the Company's future growth, results of operations, performance, future capital and other expenditures (including the amount, nature and sources of funding thereof), competitive advantages, business prospects and opportunities. Such forward looking statements reflect the Directors' current beliefs and assumptions and are based on information currently available to the Directors.