BBC News - Zoie O'Brien and Peter Walker
A team of more than 200 engineers and technicians are halfway through a five-month project to resurface London Stansted Airport.
Work on the 1.9 mile-long (3km) runway - equivalent to the size of 25 football pitches - has to be timed meticulously overnight while fewer flights are scheduled.
The engineering firm Lagan began the project on 8 January and is aiming to complete by 6 June.
The to-do list includes:
- Lay approximately 65,000 tonnes of asphalt
- Replace about 1,500 runway lights with more energy-efficient LED bulbs
- Lay about 62 miles (100km) of new cabling