When the Minister for Transport and Mobility, Yuriko Backes (DP), said before the summer that it might be time to "start thinking about a second airport", the reaction was immediate. Luxembourg has just one 4,000-metre runway at Findel, according to data published by Lux-Airport, and the idea of a second infrastructure seems disproportionate to the size of the country. But the comparison with Gatwick puts the issue into a broader perspective, which is less about raw capacity and more about the resilience of a national system exposed to a single point of failure.

Gatwick is a European exception. With 43.2 million passengers in 2024 according to its own annual report, the London airport is considered to be the world's most efficient single-runway airport in regular commercial operation. Its main runway, 3,316 metres long, supports a declared throughput of 55 movements per hour, a very high level made possible by a combination of optimised separation procedures, taxiways designed for rapid clearance and air traffic control calibrated for high density.

Around 261,000 movements were recorded in 2024 according to statistics published by the Civil Aviation Authority, representing an average of 165 passengers per flight thanks to a fleet dominated by single-aisle Airbus A320 and Boeing 737 aircraft, which accounted for around 74% of movements. The airport offered 51.1 million seats that same year, with a load factor of 84.7% according to CAA data, which explains the capacity achieved despite having only one runway.

Freight, a highly differentiated element

This performance is not due to a longer runway or a radically different layout to that of Findel, but to an operational ecosystem and a market on a completely different scale. The south of England has more than 10 million inhabitants within Gatwick's direct catchment area, which Luxembourg also has, not within an hour but within three hours, according to our calculations. Even high growth projections for passenger traffic would not justify aiming for extreme throughputs. Luxembourg's throughput is around a dozen movements per hour, a level compatible with the size of the market, the mix of traffic and freight management requirements.

It is precisely in this area that the comparison stops short. Gatwick handled around 112,700 tonnes of freight in a recent year, according to a sector summary, while Findel handled 830,468 tonnes of cargo in 2024, according to official figures from Lux-Airport, a level that makes it one of Europe's leading cargo airports. Luxembourg relies on cargo for an essential part of its economy, and coexists with passenger flights, sensitive night-time operations and heavy aircraft, requiring longer sequences and more complex planning than at an airport focused on passengers. The closure of the airport at the end of the day last week because a small aircraft missed its landing illustrates the limitations of the system.

However, Gatwick provides a useful lesson: how saturated infrastructure can be transformed within a strict regulatory system. The UK has just concluded one of the longest airport planning processes in recent history. After 18 months of public enquiry and more than 10 years of debate, on 21 September the UK government granted a Development Consent Order authorising the regular use of Gatwick's northern runway, which until now has been reserved for emergencies. The project, known as the Northern Runway, involves moving the runway slightly and equipping it for simultaneous use with the main runway. The investment is estimated at £2.2 billion, financed entirely by the private sector. The authorisation should enable Gatwick, which handled 43.2 million passengers in 2024, to increase its capacity to 80 million passengers a year. The plan also includes new taxiways, terminal extensions, upgraded road and rail access and environmental compensation areas.

Up to 13.700 jobs by 2047

The anticipated economic effects weighed heavily in the government's decision. According to the official assessment published by the Planning Inspectorate and validated by the UK Department for Transport, the project could create around 4,500 jobs by 2029 and up to 13,700 direct, indirect and induced jobs by 2047, including more than 3,000 on the airport site. The annual gross value added from the operation of this second runway is estimated at around £550 million for the south-east region. A £20 million fund is earmarked for training, work inclusion and social support for local communities, while the construction site, scheduled to run until 2029, will mobilise several hundred additional jobs in construction and associated services.

The regulatory process was particularly demanding. Five independent commissioners examined the dossier, producing a report of more than a thousand pages. Their initial recommendation was for a refusal, due to concerns about noise, emissions and traffic. After substantial amendments, the report finally recommended a qualified approval. The British Transport Minister, Heidi Alexander, approved the revised version on the grounds that the economic benefits and the project's consistency with the "Jet Zero 2050" strategy outweighed the negative impacts. The government imposed a Noise Operating Restriction in line with European Regulation 598/2014, ongoing noise monitoring, an annual audit of CO₂ emissions and strengthened sustainable transport obligations. Night-time operating limits and funding for environmental compensation measures have been included in the final decree. Gatwick thus becomes a textbook case: a major development approved under strict conditions in a regulatory context comparable to that of the European Union.

Faced with this British reality, the Luxembourg case raises very different questions. Findel is operating correctly and still has room for growth, but it remains vulnerable because of its single-site nature. A major incident would simultaneously immobilise passenger traffic, cargo operations, diplomatic connectivity and certain essential logistical flows. The debate opened by the Minister is not about the need to reproduce a model of density comparable to Gatwick, but about whether Luxembourg can continue to depend on a single airport. Gatwick shows how an airport can optimise a single runway, but above all the extent to which a country can equip itself with a binding regulatory and technical framework to strengthen a strategic infrastructure. Luxembourg needs to decide whether its aviation future lies in optimising Findel or in gradually diversifying its infrastructure to guarantee the continuity of its operations in the decades to come.