Plans for a wind turbine in Oxford have been put on hold because of the risk it could interfere with nearby RAF radars.
Partnerships for Renewables (PfR) said it would not pursue the Cutteslowe Park site proposal after discussions with the Ministry of Defence (MoD).
Studies are continuing at a second site at Oxford Road near Horspath.
The tip of the finished turbine would be as tall as the London Eye. The MoD said it would not object to a planning application without due reason.
Tony Duffin, from PfR, said: "It is not uncommon for a potential commercial-scale wind turbine to face some form of aviation issue during the development process.
"In this case it's the potential impact on existing radars at RAF Benson and RAF Brize Norton.
"We have always said that we will only proceed with a development if the site is found to be suitable for a wind turbine.
"If we cannot find a suitable solution then the investigation work will stop."
An MoD spokesperson said: "We will always do what is practicable to work with wind energy developers to find mutually acceptable solutions.
"Wind turbines are huge reflectors of radar signals and the effects are made many times worse when the turbines blades are rotating.
"Where they are in direct line of sight to the radar they have a number of effects regardless of the distances between the turbine and the radar.
"Turbine blades can create 'clutter' on the radar screens which can be identical to returns from real aircraft, mask radar returns from real aircraft and create 'holes' in radar detection which means that aircraft might not be detected at all as they fly over or close to the turbine."
Oxford City Council owns the land, although PfR will cover the development costs of the turbine.
Councillor John Tanner said: "It is a big disappointment that the wind turbine site at Cutteslowe is being put on hold by Partnership for Renewables, but we absolutely understand that Oxford's wind turbines must not compromise RAF radar systems.
"We wish PfR every success in finding a technical solution to the radar problem with the Horspath site as work on that wind turbine site continues."
Environmental and technical studies are continuing at the Oxford Road site.
A planning application for a temporary monitoring mast to gather wind data is expected to be submitted after further consultation with the MoD.