Honeywell (NASDAQ: HON) is collaborating with Boeing and the University of Reading on a project funded by the Aerospace Technology Institute (ATI) Programme to develop an aircraft-based prototype sensor designed to improve the understanding and mitigation of climate impacts from aircraft creating contrails. This research and development project, named Project MIST, will focus on advancing in-flight atmospheric sensing capabilities to increase the accuracy of contrail forecasting and enhanced weather modelling. Contrails are clouds of ice crystals formed when hot, humid jet engine exhaust mixes with extremely cold, high-altitude air.
Honeywell will lead on sensor hardware integration and systems engineering, drawing on its proven track record of maturing sensing technologies for aircraft deployment. The work will leverage Honeywell’s UK engineering and manufacturing capabilities, including its Yeovil site, alongside global support across its Aerospace business.
Boeing will contribute aircraft integration, test and operational expertise, supporting the evaluation of sensor performance in representative aviation environments and applying its deep knowledge of contrail formation and mitigation strategies. This work will be undertaken by a team at Boeing’s Bristol site, with support from a team in Seattle, US.
The University of Reading, through its Department of Meteorology, will provide contrail modelling and climate analysis expertise. The department has led research into the climate impacts of aviation for more than three decades and plays an active role in national and European non-CO2 research initiatives, including participation in the European Union Aviation Safety Agency’s Aviation Non-CO2 Expert Network, ANCEN.
"There is a clear need across the aviation ecosystem for more accurate, high-frequency atmospheric data collected in flight. By advancing aircraft-based sensing technologies, this project aims to help close critical data gaps that affect contrail forecasting, weather modelling and climate analysis."
— Anthony Florian, President, Honeywell Aerospace Europe, Middle East, Africa & India
As the aviation industry increasingly addresses the non-CO2 effects of flight, airlines, meteorological agencies and researchers are seeking more accurate, high-frequency in-flight data to inform decision-making. This project will develop a prototype humidity sensing capability that can be integrated onto aircraft platforms to help validate and enhance numerical weather prediction models and support emerging contrail-avoidance strategies.
Contrail formation is influenced by humidity and temperature values that are not consistently captured by today’s in-service instrumentation. Existing humidity sensors have limited measurement capabilities and adoption across commercial fleets, while alternative technologies often require significant redesign to enable widespread airline deployment. Addressing these challenges is critical to improving forecasting accuracy and reducing uncertainty around aviation’s non-CO2 climate impacts.
“Our aircraft already serve as meteorological platforms to provide data on winds, temperature, icing and turbulence in support of our customers and industry global operations,” said Dr. Tia Benson Tolle, Boeing Commercial Airplanes Product Development Sustainability director. “We are excited to work with ATI, Honeywell and the University of Reading on a new water vapor sensor capability, as humidity observations are essential to improve weather and contrail forecasting.”
"Frequent, high-quality measurements of humidity are crucial for calculating the climate impact of flights and one day reduce that impact,” said Nicolas Bellouin, Professor of Climate Processes, University of Reading. “In Project MIST, the University of Reading will study how better sensors and an optimised use of aircraft equipped with those sensors allow better contrail predictions, which will be a critical component of future contrail mitigation actions."
“When developing the world’s first Non-CO2 Technologies Roadmap in 2024, the ATI identified a pressing need to better predict where contrails will form and how persistent they will be,” said Adam Morton, Head of Technology for Sustainability and Strategy at the Aerospace Technology Institute. “A key requirement for achieving this is advanced humidity sensor technologies that are able to be deployed routinely in commercial aircraft. We are therefore delighted to add this project to the pre-existing projects already underway in the ATI Non-CO2 Programme.’’
“Better humidity and atmospheric data collected in-flight is essential if we’re going to cut aviation’s non CO2 impacts — including jet exhaust trails — and keep the UK leading the world on greener air travel,” said Chris McDonald, Industry Minister. “Through the ATI Programme and our Modern Industrial Strategy, we’re backing this collaboration between Honeywell, Boeing and the University of Reading to turn world class science into real world technology that supports skilled jobs and helps deliver Jet Zero.”
The collaboration aligns with the ATI Programme’s Non-CO2 Technologies Roadmap and supports the UK aerospace sector’s contribution to Destination Zero, the shared commitment between industry and government to achieve Net Zero aviation. By advancing sensing technologies today, the project is intended to help the aviation ecosystem prepare for evolving environmental expectations and future regulatory frameworks.
Honeywell will lead the project from its Yeovil, United Kingdom facility. The location provides extensive engineering, development and test capabilities, including altitude chambers and specialised facilities used to validate air and thermal systems across civil and defence platforms. Honeywell has a long history of supporting aviation innovation in the UK, with operations dating back 100 years.
The ATI Programme co-funds industrial R&D projects to develop new cutting-edge aircraft technology. The programme is coordinated and managed by the Aerospace Technology Institute, the Department for Business and Trade and Innovate UK (part of UK Research and Innovation).
