NEW DELHI: By the end of this year, air travel time in certain sectors may become shorter with commercial flights no longer needing to skirt restricted airspace zones. The civil aviation and defence ministries are working on the concept of Flexible Use of Airspace ( FUA ), which would allow both military and commercial flights to use such designated airspace with prior permission.At present, more than 35% of the Indian airspace is earmarked for defence use, and so restricted for civilian flights. In such a scenario, many navigational routes are not aligned along the shortest flight passage between airports, and require commercial flights to take circuitous paths that require additional fuel and time. Government officials say the implementation of FUA will also help bring down carbon emissions by cutting down on fuel use.The first airspace management cell (AMC), which will coordinate pre-tactical and tactical allocation of temporary restricted airspace between civil and military aviation authorities, is likely to become operational by December at Delhi Air Traffic Control. “The AMC would constitute of officers from the Indian Air Force, Indian Navy, airline representatives, airport operator and the Directorate General of Civil Aviation,” informed a senior civil aviation ministry official. “The first unit at Delhi will work on trial for a few months, and depending on results, similar units will be set up in Chennai, Mumbai and Kolkata.”Officials say that apart from bringing down fuel cost and flight time, FUA will also allow optimum utilisation of airspace. “Under FUA, the airspace designated to one authority will be allowed for use to the other for a temporary period,” explained an official. “Twenty-five Temporary Segregated Areas and Temporary Reserved Areas, as these zones will be known, have been established along with 10 conditional air routes passing through them. Civil and military personnel are currently undergoing training to understand the concept in depth.”In countries like the US, UK and Belgium, the shared use of airspace has been successfully implemented. Before starting with FUA in India, a high level delegation comprising officials of the defence and civil aviation ministries, the Indian Air force, DGCA and Airports Authority of India visited these nations to study the global best practices of such arrangements.In 2008, the delegation submitted a report that recommended the setting up of the National High Level Airspace Policy Body (NHLAPB) that would oversee a three-tier airspace management model. Officials said the report also mentioned that NHLAPB should decide on the harmonisation and standardisation of civil and military ATC systems and airport infrastructure, the sharing of data and the provision of common inputs.