The operator of Scatsta Airport says it will object to initial plans for a wind farm of up to 63 turbines in the north of Yell due to concerns over the effect the proposed development could have on aircraft operations.
Serco believes the 200MW wind farm could, in its current design, have a "significant impact" on the approach to and climb out from the North Mainland airport, with potential for communication problems with planes and helicopters.
It is also concerned that the turbines, with a hub height of up to 100m, could "generate unwanted clutter on air traffic control display screens", potentially masking aircraft.
But it said it is open to the proposals being changed in mitigation to its concerns.
Serco's letter of objection, written by contract/airport director John Thorne, follows concerns it initially raised in 2016 in relation to Peel Energy's proposed Beaw wind farm, also in Yell, which ultimately received consent from the Scottish Government in December.
Thorne said the proposed windfarm – which has been devised by local consortium Energy Isles Ltd and would also need government approval – said the location of the turbines would be "directly aligned with the flight path to the Magnus offshore installation, among others".
Energy Isles Ltd said it would not comment on individual objections and would look at all responses together with the government's energy consents and development unit when appropriate.
The proposed development, which is in its primary stages, would be located around 1.5km west of Cullivoe and 1.1km south of Gloup.
The boundary of the site would be around 26km north of Scatsta Airport, which is located between Brae and the Sullom Voe oil terminal and handles between 14,000 and 20,000 plane and helicopter flights a year for the oil and gas industry.
"In its proposed location, the development may have a significant impact on the final approach track and climb out, requiring amendment to the instrument flight procedures (IFP)," Thorne said.
"Not withstanding that the development is situated beneath the main inbound and outbound route to and from Scatsta Airport, the location of the turbines is directly aligned with the flight path to the Magnus offshore installation (among others) and Serco is specifically concerned that the development may adversely affect communications with fixed wind and rotary aircraft travelling on this flight path."
Serco also noted that there is "insufficient information provided in a number of respects in order to enable proper assessments of the application to be undertaken" at this stage.
Scatsta Airport is one of a host of proposed consultees alongside the likes of Historic Environment Scotland, the RSPB, Sullom Voe Terminal and the Unst and Yell community councils.
The proposed wind farm would be reliant on a subsea interconnector cable being laid to the Scottish mainland to allow large Shetland renewable projects to export energy.