I would assume the eyewitness accounts are true for the most part. Why? Because a rash of UFO sightings were reported in the SW US during the testing phase of the first generation stealth aircraft. And also because if I were a project manager for the DoD, the activities currently being witnessed would be a direct result of the testing phase of the kind of project plan I would develop.

1. The design specifications for a second generation stealth aircraft would be to build on it's invisibility to radar by making the newer models, as practically as possible, invisible to observers. This would include being able to run as silently as possible for a given distance and the surface would be able to absorb as much light as possible giving it a "hole in the sky" appearance. In addition, the aircraft should be made of lightweight materials and large enough for bombing missions, troop deployment and have a wing span consistent with an ability to "glide" at relatively low speeds.
2. I would "accidently" leak information that the next generation aircraft we are currently working on being some mysterious "Aurora" type aircraft, very fast capable of sub-orbital flights. Meanwhile we would be producing prototypes of the aircraft mentioned above.
3. For testing purposes, the prototype aircrafts would be deployed on missions to fly over populated areas to assess the performance by determining the number and type of sightings reported and the number of sightings published or broadcasted in local media.

Methinks they see a new plane!

Bill