Two commercial planes had a near miss in the skies above Houston's George Bush Intercontinental Airport Thursday night, the Federal Aviation Administration said. A Singapore Airlines flight took off shortly before 7 p.m. and the pilot did not level off when he reached 4,000 feet as required. This resulted in the outbound plane being less than 2,000 feet away from a Delta Air Lines flight which was preparing to head into Houston for landing. The incident happened about 10 miles northeast of the airport.

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"The Federal Aviation Administration (FAA) is investigating a loss of required separation that occurred Thursday evening between two jetliners while in airspace controlled by the Houston Terminal Radar Approach Control," a statement said. "An air traffic controller noticed the deviation and issued traffic alerts and instructions to the pilots of both aircraft." The FAA said it did not yet know exactly how close the two planes came. "The FAA has taken steps to ensure that all flight crews are aware of the top altitudes for standard departure routes."

- Christina Boyle