The Dutch Accident Investigation Board's preliminary report into the Turkish Airlines 737 crash at Amsterdam's Schiphol Airport has reinforced previous safety warnings issued by AEI. The engineering group has been warning for some time that completely avoidable accidents such as this will increase unless regulators start to properly enforce the regulations. Dutch investigators revealed that an altimeter on the airliner was defective on at least two occasions prior to the fatal flight without being reported by the flight crews. "We have warned the authorities and in fact supplied evidence of pilots not reporting faults with their aircraft as they occur but rather when commercially convenient, yet the issue continues to be ignored," said AEI's Secretary General Fred Bruggeman. In 2007 and 2008, AEI repeatedly warned European aviation authorities about pilots not reporting aircraft system defects but unfortunately the warnings were ignored. AEI would like to see aviation authorities increase their surveillance of airlines in order to guarantee that standards are being met.