Project Tip Tow
October 20th, 1950, the United States Air Force continues long term and creative innovations to extend the force projection of piston engine bombers. Perhaps one way to increase the range of strikes on enemies in battle would be for a bomber like a B-29 to tow into theatre two F-84 fighter aircraft. One of these experiments produced mixed results: one crew died when starboard 84 crashed into the bomber. But several successful flights of these wing tip configurations were launched and several attachment and detachments were performed. This was called Project Tip-Tow.
F-84s maintained manual control of their flight surfaces but engines were shut down to conserve fuel.
Source: Dark Roast Blend, Wikipedia.