Birmingham International Airport has been accused of "naked commercialism" in its attempts to halt development of a rival hub.
The claim was made by Coventry Airport during the opening day of a public inquiry into its proposed permanent terminal - capable of handling two million passengers a year.
BIA opposes planning permission being granted to the terminal because of fears increased operations at the nearby Baginton airport will hinder its own plans for a second runway.
In its opening submission, Coventry said the BIA objections were "misconceived and threadbare, exposing the naked commercialism beneath".
Lawyers representing Coventry were heckled at the inquiry, due to run for more than two months.
Shouts of "Mills and Boon" - relating to claims that the plans were 'fiction' - were heard as Peter Village QC made the opening statement.
The inquiry centres on permission for the construction of a passenger terminal, car park, aircraft parking and improved access to the airport.
The remarks were made at the meeting at Leamington Town Hall as Mr Village said the plans would not have a material impact on ecology, nature conservation or bird strike risk, but would improve the unemployment situation in the region.
John Steel, QC, for BIA, said: "Coventry Airport is located approximately 11 miles south-east of BIA and lies beneath, but within the lateral limit of the Birmingham-controlled airspace area.
"Such close proximity combined with the conflicting alignment of the runways approximately at right angles, creates an interface between traffic patterns of the two airports...
"This currently results in delays to some air traffic at Birmingham International Airport and Coventry Airport at peak periods."
He said the airspace conflict between the two airports had been recognised by the Civil Aviation Authority (CAA) but stressed the importance of making BIA's expansion plans a priority over Coventry's, in line with a Government's Aviation White Paper.
He claimed The Future of Air Transport identified BIA as the site for a new runway to meet long term demand for air transport in the Midlands. It stated that passenger fore-cast figures are expected to increase to in excess of 32 million per annum by the year 2030, with a new runway needed by 2016.
Representatives for the CAA are to give evidence regarding the impact of airspace conflict in the coming weeks.
Members of The Community Group, featuring organisations from Warwickshire and Coventry, said many people were concerned for their quality of life. Roger Fawcett, representing the group, said there would be an increase in noise, pollution and adverse effects on the ecology if the airport received planning permission.
The hearing continues.