Two unique aircraft now ready to start flight tests are waiting on the ground as crews deal with various glitches. Doc, the B-29 that has been under restoration for years, finally flew last month, but the flight lasted just 15 minutes, shorter than was planned. The flight was cut short after a chip detector device, which monitors the presence of metal debris in the engine, lit up. Also, the Airlander, the huge lighter-than-air vehicle under development in the UK by Hybrid Air Vehicles, exited its hangar last week, but the first flight, expected on Sunday, was delayed at the last minute.
Source: avwebFlights Delayed For Airlander And Doc