Air quality - developing more efficient operating procedures

Take-off procedures

By using the minimum thrust allowed for take-off for all of our operations, we are able to minimise the amount of NOx emissions from our aircraft.

The technique we use (called the 'Assumed temperature' technique) is safe and widely practised and is the most effective way of reducing NOx emissions during take-off.

Landing procedures

Reducing the aircraft flap angle on approach allows a small reduction in thrust levels and results in lower NOx emissions. Using reverse idle thrust only, on the landing roll, also helps to reduce Nox emissions.

Surveys carried out by British Airways and BAA suggest that about 60% of all aircraft landing at Heathrow, only use idle power for reverse thrust. For our aircraft, this figure rose to above 90% of landings using only idle power.

Auxiliary Power Units (APU)

The Auxiliary Power Unit's (APU) and Ground Power Unit's (GPU) for aircraft - the source that powers aircraft whilst on the ground - can contribute up to about 20% of all ground level NOx emissions. Reducing the time the APUs and GPUs operate is of great importance to us.

To be able to reduce their operating times further requires electrical power and conditioned air from terminal sources. Although many of the airports we operate to have fixed ground power, only a few also provide conditioned air supplies. Our new home at Terminal 5 is able to supply both enabling us to reduce our NOx emissions at Heathrow significantly.