Planning

Project CALLISTO (PROPULSION)

MINISTRY OF DEFENCE

This public procurement record has 1 release in its history.

Planning

04 Jun 2025 at 14:50

Planning Notice
Summary of the contracting process

The Ministry of Defence (MOD) is currently in the planning stage of a procurement process for Project CALLISTO (PROPULSION), which focuses on military research and technology within the United Kingdom. The project seeks to develop a low-cost, 1.2-2kN propulsion system for the UK MOD's development programme, Proj BRAKESTOP. This initiative is significant due to its potential applications in heavy One Way Effectors and possibly other areas such as cruise missiles. A Project CALLISTO Challenge Session is scheduled for 18th June 2025 in London, with responses due by 10th June 2025. The MOD aims to commence full rate production of 20 engine units per month by Q2/Q3 2026, and is open to purchasing proven, off-the-shelf systems that promise security of supply.

This tender represents a substantial opportunity for businesses proficient in designing or manufacturing propulsion systems, particularly those with experience in creating cost-effective and scalable solutions. The MOD is targeting a unit price of £75K per propulsion system and is willing to support the development of new solutions if existing products fail to meet specifications. The project's broad technical requirements at this stage make it accessible to a range of companies, creating an environment ripe for innovation and collaboration. Firms established within the UK or planning to do so could gain a significant advantage in capturing a share of this lucrative defence sector opportunity.

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Notice Information

Notice Title

Project CALLISTO (PROPULSION)

Notice Description

The UK MOD will be holding a Project CALLISTO Challenge Session on the afternoon of the 18th June 2025 in London, UK. Industry partners, particularly those currently established or planning to be established in the UK, are invited to attend to provide feedback on Project CALLISTO's proposed scope, timescales and feasibility. Additional information: The User requires a low-cost, 1.2-2kN propulsion system to power a UK MOD development programme (Proj BRAKESTOP) for a heavy One Way Effector (OWE). The propulsion system could be used for other applications e.g. cruise missiles, other OWEs. Project BRAKESTOP has highlighted limited availability of the class of propulsion systems needed. Therefore, MOD wishes to increase the availability of this class of propulsion system. Technical Propulsion Engine Requirements The engine shall: * Be a 1.2 - 2kN single engine propulsion system (Sea Level Static Maximum Thrust) o Low end for least amount of ancillary cost (facilities, fuel, equipment, build material, machine size, test cell etc) o Could then be iterated for enhanced capability. * Be designed to be easily manufactured at scale using widely available manufacturing methods/machinery. * Manage at least 5 hours component life; this provides confidence in managing the expected application life, but also pushes the materials technologies to low cost. * Be able to reliably start rapidly (ideally < 30 seconds) and accelerate to high power (ideally <10 seconds). o Reduced warfighter exposure is important. * Demonstration within 9 months ready for Q1 2026. o Demonstrate to then iterate pushing the competitor's ability to learn and adapt to risks arising given engine testing. * Within 12 months, be prepared for full rate production of 20 engines a month. It should: * Be resilient to -15 to +40 degrees. * Be resilient to fuel type. * Be readily adaptable for spiral development towards enhanced capability. * Be cost effective against equivalent market competitors in this thrust class. * Be resilient to typical transport vibration. Procurement Approach and Timeline MOD's preferred approach is to purchase a proven, off-the-shelf propulsion system of the desired technical and cost characteristics from a supply chain which can guarantee security of supply of the quantities required Q2-Q3 2026. Currently, there are several different consortiums building a range of solutions against the BRAKESTOP requirement. The technical requirements are therefore deliberately broad at this stage but will be refined as BRAKESTOP solutions are eliminated from the competition over late 2025 and into 2026. Pricing Information Target (Propulsion System) Unit Price: PS75K Target (Propulsion System) Volume: 20 units per month from Q2/Q3 2026 to support Project BRAKESTOP If there is no off-the-shelf solution that meets this requirement, MOD is willing to consider additional funding for development of a new propulsion system(s). Challenge Day Information The Authority will be holding a Project CALLISTO Challenge Day on the afternoon of the Wednesday 18th June 2025 in the STADIUM room at Scalespace in London, UK. Please use the following link to submit a request form to attend the Challenge Day. MOD will consider the track record of companies of designing and/or manufacturing propulsion systems will be allowed to attend the event - it is therefore key that you provide examples of your expertise. Please note that responses must be submitted by 10th June 2025. Due to capacity limitations, this Challenge Day will be limited to 4 personnel from each company. In the event of the location's capacity being exceeded, the MOD will restrict down to 1 person from each company. https://forms.office.com/Pages/ResponsePage.aspx?id=7WB3vlNZS0iuldChbfoJ5a5yEC87bndDi9PKmMmNOy9UN1ZYRkhMSkczNjBTOTlaUlBKTzREQ0w4VS4u

Notice Details

Publication & Lifecycle

Open Contracting ID
ocds-h6vhtk-0542f8
Publication Source
Find A Tender Service
Latest Notice
https://www.find-tender.service.gov.uk/Notice/029983-2025
Current Stage
Planning
All Stages
Planning

Procurement Classification

Notice Type
Planning Notice
Procurement Type
Standard
Procurement Category
Services
Procurement Method
Not Specified
Procurement Method Details
Not specified
Tender Suitability
Not specified
Awardee Scale
Not specified

Common Procurement Vocabulary (CPV)

CPV Divisions

35 - Security, fire-fighting, police and defence equipment

73 - Research and development services and related consultancy services

CPV Codes

35613100 - Unmanned combat aerial vehicles

73410000 - Military research and technology

Notice Value(s)

Tender Value
Not specified
Lots Value
Not specified
Awards Value
Not specified
Contracts Value
Not specified

Notice Dates

Publication Date
4 Jun 20258 months ago
Submission Deadline
Not specified
Future Notice Date
Not specified
Award Date
Not specified
Contract Period
Not specified - Not specified
Recurrence
Not specified

Notice Status

Tender Status
Planned
Lots Status
Not Specified
Awards Status
Not Specified
Contracts Status
Not Specified

Buyer & Supplier

Contracting Authority (Buyer)

Main Buyer
MINISTRY OF DEFENCE
Contact Name
FCI Commercial, attn: FCI Commercial
Contact Email
desgtwy-fci-ercoe-comrcl@mod.gov.uk
Contact Phone
Not specified

Buyer Location

Locality
BRISTOL
Postcode
BS34 8JH
Post Town
Bristol
Country
England
Major Region (ITL 1)
TLK South West (England)
Basic Region (ITL 2)
TLK5 West of England
Small Region (ITL 3)
TLK52 Bath & North East Somerset and South Gloucestershire
Delivery Location
Not specified
Local Authority
South Gloucestershire
Electoral Ward
Stoke Park & Cheswick
Westminster Constituency
Filton and Bradley Stoke

Further Information

Open Contracting Data Standard (OCDS)

View full OCDS Record for this contracting process

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The Open Contracting Data Standard (OCDS) is a framework designed to increase transparency and access to public procurement data in the public sector. It is widely used by governments and organisations worldwide to report on procurement processes and contracts. 

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