Checking aerodrome and defence safeguarding zones

Safeguarding zones around aerodromes, defence technical sites and military explosives storage areas are consultation triggers, not designations you will see on most constraint searches. A site can sit inside one without anything appearing on a commercial report, and the first sign is a consultation response objecting to a building you thought was uncontentious. Check at the start, because the fixes are usually about height and position, and both are expensive to change after a design is settled.

The check is quick. Ask the local planning authority whether the site falls within a safeguarded area, and ask which safeguarding authority is involved.

What safeguarding protects

Civil aerodrome safeguarding protects the surfaces aircraft need to be clear of obstacles, the operation of navigation aids and radar, and the approach and departure paths. A structure that penetrates an obstacle limitation surface, or that sits where it degrades a radar picture, is a flight safety issue rather than an amenity one.

Defence safeguarding does the same for military aerodromes and adds two further categories. Technical sites, which include radar heads, communication installations and aircraft guidance equipment, where the concern is interference. And explosives storage areas, where the concern is the consequence of an incident and the control is on new development within defined distances.

None of this is negotiable in the usual planning sense. Where the safeguarding authority objects on a flight safety or a defence basis, a council will rarely grant permission against that objection, and an inspector is unlikely to take a different view.

Where the maps are held

Officially safeguarded aerodromes and defence sites have safeguarding maps deposited with the relevant local planning authorities, and the authority is required to consult the safeguarding authority on development of the types shown on those maps. The deposited map is the authoritative record.

Ask the council's planning department directly. Some authorities show safeguarded areas on the adopted policies map, some publish the safeguarding map separately, and some hold it internally and check it during validation. A pre-application enquiry that asks the question in terms, naming the aerodrome or site if you know of one nearby, gets a usable answer.

National datasets are improving, and some safeguarding layers now appear alongside other planning data on the national planning data service, which is worth checking as a cross-reference rather than as a substitute. For defence sites, the Defence Infrastructure Organisation handles safeguarding enquiries and will confirm whether a site is affected.

Unlicensed aerodromes and private airstrips have no statutory safeguarding, but an operator may still be consulted informally and a council may still attach weight to their response. Establishing what is adopted and what is discretionary here follows the same pattern as checking whether the strategic road network is engaged.

Development types that trigger consultation

The maps define zones with height thresholds that fall as you approach the aerodrome, so the trigger is a combination of location and height rather than height alone.

Typical triggers are buildings and structures above a stated height within a defined radius, wind turbines and other tall slender structures, lighting installations, works affecting the ground profile such as significant earthworks, and development that could attract birds. Explosives storage areas trigger on the type and occupancy of the development rather than its height.

Bird attraction covers more than landfill. Attenuation ponds, balancing lakes, reedbeds, green and brown roofs, food waste processing, open-air food service and amenity grassland all appear in safeguarding responses. Waste and landfill proposals are commonly consulted over a wide radius, often measured in kilometres rather than metres, so a rural site can be caught a long way from a runway.

Solar photovoltaic installations trigger a different concern, which is glint and glare affecting pilots on approach and controllers in a tower.

Cranes and temporary structures

A tower crane is often taller than anything in the permanent scheme, and safeguarding applies to it even though it is temporary and even though it does not need planning permission in its own right.

Aerodrome operators run crane notification procedures, and the contractor has to obtain clearance before erecting a crane within a safeguarded area, usually giving the position, the maximum height above ordnance datum, the jib radius and the period of operation. Conditions requiring a crane management plan are common on sites near an aerodrome, and they are easier to satisfy if the requirement is known before the contractor is appointed.

Scaffolding, piling rigs, temporary masts and even a telehandler with a raised boom can fall within the same procedure. Put the question to the aerodrome at design stage and include the answer in the construction management information submitted with the application.

Bird strike and landscape design

Where a scheme is consulted on bird hazard grounds, the response usually asks for a bird hazard management plan and for landscape and drainage design that does not create attractive habitat.

The design consequences are specific. Open water is discouraged, and where attenuation is required the preference is for dry basins, underground storage or features designed to drain down quickly rather than permanent ponds. Planting schedules avoid species producing fruit or seed attractive to flocking birds. Green roofs may be resisted or restricted to sedum with a management regime. Refuse and food waste storage has to be enclosed.

This runs directly into drainage design, so raise it before the Flood Risk Assessment and drainage strategy are fixed. A scheme that has committed to an attenuation pond in its surface water strategy and then meets a bird hazard objection has to redesign both.

A bird hazard management plan secured by condition typically covers landscape maintenance, waste storage, the drainage regime, monitoring and a contact point for the aerodrome. Draft it with the aerodrome's safeguarding team rather than presenting it to them.

Lighting and glint

Two distinct lighting issues arise.

The first is confusion with aeronautical ground lighting. External lighting that resembles runway or approach lighting in colour, arrangement or intensity can be objected to, and the answer is usually a lighting design with controlled upward light, specified colour temperature and a layout that does not read as a linear array from the air.

The second is glint and glare from reflective surfaces, chiefly solar panels but also glazed facades and metal roofs. Where a scheme is near a flight path or within sight of a control tower, a glint and glare assessment models the times of year and day when reflected sunlight could reach a pilot's eye or the tower, and proposes mitigation through panel orientation, tilt, anti-reflective coating or screening.

Both assessments take less time and cost less if they are done before the elevations are fixed.

Engaging the safeguarding authority early

Treat safeguarding as a pre-application matter rather than a consultation response to be answered.

Ask the council whether the site is in a safeguarded area and which authority is involved. Contact that authority with the site location, the maximum height above ordnance datum of the proposal, including plant and lift overruns, and an outline of the drainage and landscape approach. Ask specifically about crane requirements and about any bird hazard concerns.

Get the response in writing and put it in the application. A safeguarding authority that has seen the scheme and raised no objection is a consultee who will not derail the determination, and a safeguarding authority that has asked for changes has told you what they are while changing them is still possible.

Confirm other route and access constraints such as public rights of way on the definitive map at the same time. Enter your postcode on PlanScope to see which reports your site is likely to need.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. This is general guidance rather than legal advice, and safeguarding status should be confirmed with the local planning authority and the safeguarding authority.