Aviation regulator DGCA has grounded 11 pilots of infrastructure major GMR for three months.DGCA sources said that DGCA's unprecedented move came after the regulator's team found that several flights operated by GMR Aviation in the last month, including one on Monday when an aircraft flew Congress Vice President Rahul Gandhi to Bhubaneshwar, had skipped some mandatory tests.They said, the tests included the pre-flight breath analysis of pilots and cabin crew, with the breathalyser equipment being non-functional.The regulator also decided to act against the company's doctor for issuing pre-flight medical certificates to the crew even when the breathalyser equipment was not working for almost a month.Pre-flight breathalyser tests are mandatory for all flights boarded by the VIPs protected by the Special Protection Guard, SPG.Meanwhile, GMR Aviation today strongly refuted the charges of violation of safety norms levelled by DGCA. They said that no test has been skipped. Confirming that they had received the DGCA notice, a spokesperson of the company owned by GMR said, a written response would be shortly sent to the aviation regulator. He expressed the hope that the suspended 11 pilots would be reinstated soon.