sentences:  On January 4, after the aircraft rendezvoused over the Imperial Valley, both nearly impacted the ground when they encountered an unexpected air pocket while refueling.Hoyt developed a system whereby Woodring tugged on a string tied to the pilot's arm if the C-1's speed was excessive.Early in the flight a window blew out of the C-2's cabin, but a replacement was eventually hauled up and installed by Hooe.