Both helicopters droped into the lake because they did not have enough power to stay in their hovering positions, Lt. Aaron Kakiel, spokesman for the Naval Air Forces command at North Island, where the pilots are based, told the San Diego Union-Tribune.
The helicopters were on their way back to the air station in San Diego after an air show in Sacramento. They were headed to Lemoore Naval Air Station south of Fresno for refueling when the incident occurred.
Afterward, the helicopters had to land at Lake Tahoe airport for repairs. The incident caused between $50,000 and $500,000 in damage to the choppers.
Watch the dramatic video below and read more at the San Diego Union-Tribune.
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