Draft Sectoral Marine Plans for Offshore Renewable Energy in Scottish Waters: Socio - Economic Assesment

The study reported here provides a high level socio-economic appraisal of the potential costs and benefits to activities that may arise as a result of offshore wind, wave or tidal development within the Draft Plan Options as part of possible future Scotti

B2. Aviation

B2.1 Overview

This sector relates to civil aviation, which comprises scheduled air transport (including all passenger and cargo flights operating on regularly scheduled routes) and general aviation (including all other civil flights, private or commercial). Military aviation is covered separately in the Military Interests baseline. Figure B2 shows an overview of aviation activity in relation to the Draft Plan Option areas. Information sources used in the assessment are listed in Table B2.1.

Table B2.1 Information Sources


Information Available




UK Air Passenger Demand Forecasts


Department for Transport (2009)


Scottish Transport Statistics


Scottish Government

B2.2 Future Trends

The number of air passengers using UK airports is forecast to recover from the recent downturn. In a 'constrained' forecast, in which it is assumed that there will be no new runways and only incremental developments to airport terminals to make maximum use of existing runways, numbers of passengers are forecast to rise from 211 million passengers per annum (mppa) in 2010 to 335mppa in 2030 (range 300 - 380 mppa), and to 470mppa in 2050 (range 380 - 515 mppa). These forecasts imply average annual growth in passenger numbers to 2050 of 2.0% (within the range 1.5-2.3%) significantly lower than the 3.7% average seen over the past twenty years (DfT, 2011). Unconstrained forecasts (in which it is assumed there are no airport capacity constraints) show that UK air travel would rise from 211mppa in 2010 to 345mppa in 2030 (central forecast, range 305-400mppa) and 520mppa (central forecast, range 400-700mppa) (DfT, 2011).

Constrained (maximum use) passenger capacity and ATM forecasts for major Scottish airports are shown in Table B2.2.

Table B2.2 Constrained Terminal Passenger and ATM 'Central' Forecasts for Major Scottish Airports

Numbers/ Movements Airport 2010 2020 2030 2040 2050
Terminal passengers (mppa) Glasgow 7 7 10 12 20
Edinburgh 9 13 15 20 20
Aberdeen 3 3 4 5 6
Prestwick 2 2 2 3 4
Inverness <1 1 <1 <1 <1
Air Transport Movements (000's) Glasgow 70 55 75 90 140
Edinburgh 100 170 190 230 180
Aberdeen 90 90 100 110 120
Prestwick 15 20 25 25 30
Inverness 15 30 15 15 15

B2.3 Potential for Interaction

Table B2.3 shows potential interaction pathways between aviation activities and wind, wave and/or tidal arrays.

Explanation of column content:

Column 1: Describes the potential interaction between the activity and any renewable technology;

Column 2: Identifies the types of offshore renewable development (wind, wave or tidal) for which the interaction may arise;

Column 3: Identifies the potential socio-economic consequence associated with the interaction identified in Column 1;

Column 4: Indicates whether detailed assessment will or will not be required if activity is scoped in;

Column 5: Identifies how the socio-economic impact will be assessed.

Table B2.3 Potential for Interaction






Potential Interaction

Technology Relevance
(Wind, Wave, Tidal)

Socio-Economic Consequence

Scoped in (√)
or Out (X) of Assessment

How the Economic Impact Will be Assessed

Height obstruction of commercial navigation routes (helicopters)

Wind arrays only

Additional track miles for helicopters owing to height obstruction in inclement weather

- where Draft Plan Option areas overlap with existing helicopter routes

Information on main helicopter routes ( MHRs) is available from the Aeronautical Information Publication ( NATS website).

Consultation with specific helicopter operators to discuss any particular issues for individual Draft Plan Option areas and estimate additional track miles where any issue highlighted. See Section B2.4 for detailed methodology.

Interference with radar systems

Wind arrays only

The need to provide radar mitigation for strategic en-route and low level radar interference.

X - radar mitigation will be required as a condition of consent if there is a potentially significant effect. And the costs will be borne by the developer rather than the airline industry or regulator. This essentially involves a transfer of the cost to the developer and therefore does not require assessment here.

Economic assessment not required.

To inform the Sustainability Appraisal, consultation will be undertaken with ( NATS) to identify any issues or objections to developments in each Draft Plan Option areas due to potential interference with radar systems and the scale of any issues associated with individual Draft Plan Option areas will be highlighted.

Height obstruction of commercial navigation routes (commercial aircraft)

Wind arrays only

Loss of trade at airports

X - developments that compromised air safety on approaches to and from commercial airports would not be granted consent

Economic assessment not required.

B2.4 Scoping Methodology

B2.4.1 Height Obstruction of Commercial Helicopter Navigation Routes

Helicopter Main Routes ( HMRs) represent the routes typically flown by helicopters operating to and from offshore destinations and are 'signposts' to aid flight safety ( i.e. signposting concentrations of helicopter traffic to other air space users). Whilst HMRs have no airspace status and assume the background airspace classification within which they lie, they are used by the Air Navigation Service Provider ( ANSP) ( i.e. NATS Aberdeen) and helicopter operators for flight planning and management purposes. While compliance with the HMR structure is not compulsory, in the interests of flight safety, civil helicopter pilots are strongly encouraged to plan their flights using HMRs wherever possible. The HMRs do not predict the flow of helicopter traffic ( UK Aeronautical Information Package; NATS website).

The Civil Aviation Authority ( CAA) has noted that, as a result of needing to lower their operating altitude in inclement meteorological conditions, helicopters may not be able to overfly wind farm developments, and thus would be forced to alter their track to go laterally around the sites, resulting in additional track miles, costs and emissions (Civil Aviation Authority, 2010; cited in ABPmer et al. 2011).

For the purpose of this assessment, this potential negative effect was only considered to be likely where main helicopter routes ( MHRs) intersected with a wind Draft Plan Option areas. Using this assumption:

  • Draft Plan Option areas which were not intersected by HMRs were scoped out of the assessment; and
  • Draft Plan Option areas which were intersected by HMRs were considered to require a quantitative impact assessment.

The results of the scoping exercise are presented in Appendix C2.

For the purposes of this assessment it was assumed that there was no potential for wave and tidal developments to cause any potential negative interaction with civil aviation or helicopter operations. Consultation with relevant civil aviation stakeholders confirmed that, in general, this was a reasonable assumption. However, the following information was provided by the CAA (Kelly Lightowler, CAA, pers. comm. 12 March 2013):

"Wave and tidal developments will have minimal impact on aviation as they often will not extend vertically above the surface of the water. However, during construction and maintenance there may be a requirement for tall structures such as cranes to be temporarily at the site. The CAA would ask that these temporary structures are notified through the means of a Notice to Airmen ( NOTAM). To arrange an associated NOTAM, the developer or those responsible for the site at the time should contact the CAA's Airspace Utilisation Section; they will need an accurate location, an accurate maximum height and a completion date".

B2.5 Assessment Methodology

B2.5.1 Height Obstruction to Commercial Helicopter Navigation Routes

Where wind Draft Plan Option areas were identified as potentially obstructing HMRs using the scoping methodology, it was anticipated that the potential cost impact to the aviation industry of this interaction could calculated by estimating the additional track miles required for helicopters to navigate around Draft Plan Option areas of concern during inclement weather for both inbound and outbound routes. This assessment would require generic information on helicopter flight speed (assumed cruising speed; km/h), fuel consumption (kg/hr) and fuel cost (obtained from internet searches or industry consultation). An indicative economic cost of the additional track miles could then be calculated as follows:

additional track miles (km) x cost of fuel used

Given the high number of HMRs in the Northern North Sea the additional track miles would be estimated to represent the largest deviation that would be required around a given Draft Plan Option areas of concern ( i.e. a 'worst case' scenario).

To assess the significance of this cost to the sector, the frequency of usage of the HMRs which intersect with wind Draft Plan Option areas, and the frequency of low level flying due to inclement weather would be required and this information was sought through industry consultation.

B2.5.2 Interference With Radar Systems

Mitigation for radar interference will be required as a condition of consent if there is a potentially significant effect. This cost would be transferred to the developer and hence no quantitative assessment of this cost has been undertaken. However, relevant stakeholders were consulted to ascertain whether there were any issues or concerns about any of the wind Draft Plan Option areas, and the scale of any potential issues.

Prior to undertaking this consultation with aviation stakeholders the NATS self assessment maps ( NATS, 2013) and the DECC Aviation Safeguarding Data ( DECC website), were used to identify Draft Plan Option areas which were likely to cause interference with radar systems and the outputs of this scoping exercise was discussed further with stakeholders.

The outcome of this scoping exercise and stakeholder consultation is provided in Appendix C2.


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