Aviation: Heathrow consults on airspace changes
Heathrow Airport has launched a public consultation over changes needed to support the proposed third runway. The airport is considering options for both its current and future configurations, and is seeking input from residents and stakeholders on which methods of providing extra capacity they prefer.
The proposals on which Heathrow is seeking feedback fall into six main areas:
Airspace changes - for the existing two runways, and for expansion.
Managing noise at the expanded airport.
Respite through runway and airspace alternation.
Directional preferences for runway use.
Night flights - early morning restrictions.
Night flights - other restrictions.
The airport is also making proposals to increase capacity beyond the current movements cap in the interim period before the third runway is built.
Performance Based Navigation (PBN) will be implemented, moving from outdated and conventional aircraft navigation using ground-based beacons to modern satellite navigation. PBN flight paths are narrower and more concentrated than current routes, which could increase noise in some areas. However, PBN will also increase the accuracy of the inbound tracks that are flown and allow more flexible positioning of routes. It will also help improve operational performance and reduce delays, and offers opportunities for avoidance of noise sensitive areas.
Performance Based Navigation will improve compliance with established flight routes and ensure aircraft pass over noise-sensitive areas whenever possible. (Heathrow Airport)
Changes will have to meet five critical objectives which include: maintaining safety; compliance with government requirements on airport capacity and noise; and conformance to local air quality requirements and the national Airspace Modernisation Strategy. Heathrow will also aim to meet five further goals which include: limiting and where possible reducing local noise effects; minimising fuel / CO2 / greenhouse gases; ensuring operational efficiency and resilience: designing the airspace to use the latest navigation technology; and minimising its impact on other airspace users.
Heathrow is committing to "limit and, where possible, reduce the effects of noise on health and quality of life and deliver regular breaks from scheduled flights for our communities during the day and night."
Heathrow is committing to maintain 2013 noise levels, or reduce them, despite increasing traffic. (Heathrow Airport)
It claims this means that even an expanded, three runway Heathrow, will meet goals already committed to that will ensure the overall noise impact will not exceed 2013 levels - as set out by the government's Airports National Policy Statement (NPS). This objective also dictates that as aircraft and navigational technology improves, efforts will be made to further reduce noise effects.
The consultation goes on to say that the airport "will provide predictable and regular scheduled breaks or reductions in aircraft noise while considering the effects of night flights and managing the impact of noise between 23:00 and 07:00."
During daytime hours when aircraft are landing at taking off to the west, Heathrow typically alternates the use of its two runways to provide local communities with respite for part of each day, with a switch-over taking place at 15:00. Currently one runway is used for departures while the other handles arrivals.
Heathrow is surrounded by residential communities. Frequent alternation of runway use will limit the impact on each community. (Heathrow Airport)
When the third runway is completed one runway will be used for arrivals, another will be use for departures, and the third will operate in ‘mixed mode’ (used for both departures and arrivals). Operating all three in mixed mode would deliver the most capacity but would not provide any respite to local communities. Therefore only one runway will operate in mixed mode to ensure a balance of arrivals and departures, and the middle runway will never be in mixed mode for safety reasons. Proposals point to four runway potential operating patterns:
North - mixed; Centre - arrivals; South - departures.
North - mixed; Centre - departures; South - arrivals.
North - arrivals; Centre - departures; South - mixed.
North - departures; Centre - arrivals; South - mixed.
The operating patterns will be cycled so that each community gets a share of respite. Each pattern provides respite for two local areas and 'airspace alternation' will also be introduced - depending on which runway is in use, arriving and departing aircraft will use alternating flight paths to ensure so that communities further away from the airport also get respite.
During the day a ‘westerly preference’ is currently operated at Heathrow. This means that even during periods of light easterly winds, aircraft land in a westerly direction and make a final approach over London. The wind is predominantly from the south west, so westerly operations are place for approximately 70% a year.
Landing direction may be varied to provide respite under inbound and outbound flight paths. (Heathrow Airport)
The airport is proposing to move to a ‘managed’ preference which would involve changing the direction of arriving and departing aircraft to limit noise effects on communities. Options being considered include:
Operate in a westerly direction during the day and in an easterly direction at night when the wind allows.
Breaking up periods of operating in one direction after (for example) five or seven days if the wind is low enough to permit a change.
Night flights - early mornings
The first arrivals at Heathrow are currently scheduled for 04:45 but touch down on the runways often takes place from 04:30 onward. The airport is proposing to land early morning arrivals later by either:
Scheduling flights from 05:30 (runway time 05:15) using one runway.
Scheduling flights from 05:45 (runway time 05:30) using two runways.
The night flying period may be restricted. (Heathrow Airport)
If option 1 is chosen communities would benefit from the later start on two out of every three days. Option 2 means local residents would benefit from the later start on one out of every three days, but aircraft flying over each area would be less frequent.
Night flights - other restrictions
Restrictions may limit night flights to only the quietest aircraft. (Heathrow Airport)
Heathrow already operates an over-night quota system. This allows a limited number of departures and arrivals that are delayed to operated. The periods between 23:00 and 01:00, and between 04:30 and 06:00, currently support schedule recovery. Proposals to change how these recovery periods could be used include:
Limiting the aircraft that are allowed to operate to the quietest types.
Limiting the time they can operate during the scheduled night ban.
Restricting the quota count of aircraft that can operate in the recovery period.
Conducting regular reviews of the quota count.
Pre-third runway, interim capacity increase
The airport is considering options for early growth that could be implemented once it receives formal go-ahead for the third runway. These involve increasing capacity by up to 25,000 air transport movements (ATMs - arrivals and departures) from the current annual limit of 480,000 ATMs. These developments will be subject to the airport remaining within its noise targets, will require changes to the airspace to enable parallel approaches, and confirmation of arrangements for a night flights ban.
Text © The Aviation Oracle; all photographs ©Heathrow Airport.