No, Armstrong did not invent a death ray, but I did come upon an envelope with "Death Ray" written across the front in the collection. The materials contained within it are incomplete and as a result, there are a variety of holes to this tale. Reading through the documents, let me present a synopsis:
For some years prior to 1942, a Mr. Roberts, residing in New Castle, Delaware, had been trying to sell his death ray to the United States government. He refused to make a disclosure of said invention without a definitive commitment from the government to purchase it.
In 1942, the government engaged in a tentative contract with Roberts for full disclosure of the D.R. invention. The contract called for a disclosure to be made to a board, comprising three individuals. The three would consist of an engineer, a physicist and an Army officer.
Armstrong was contacted by the government through Major Donald Lippincott, who asked if he would be willing to sit on the Board. Armstrong had also been chosen specifically by Roberts attorney, George Finch, as the engineer to fill one of the three spots. Finch acted as Roberts representative throughout the coming disclosures as Roberts was, at the time, incarcerated. He agreed to serve and signed non-disclosure documents which precluded him from discussing the death ray, at least for the next seventeen years.
Witnesses were interviewed and gave accounts as to the utility and effectiveness of Roberts creation. The death ray was said to zap ducks out of midair, some thousands of feet high (allegedly, several ducks were retrieved from the road without so much as a mark to indicate cause of death), turn green grass into yellow ribbons, and slice trees horizontally, severing the top from the bottom half.
There are a few notarized witness accounts of the ducks mysterious demise amongst the materials. The following is from William B. Davis, Magistrate at New Castle:
When I saw the ducks and I had them in my possession for a day or two they were dead, their eyes were closed, they were wet, they had not been shot, they had no sign at all as to the cause of their deaths just seemed to be stunned to death.
Major Lippincott investigated the site himself. He visited New Castle to examine any evidence that may remain from supposed death ray invention. His account of the visit is seen in the documents below.
At some point, either during the disclosure proceedings, or immediately following, Armstrong withdrew from the Board. I can not garner the reason why from the existing documents. Neither can I infer the final outcome or report that was eventually given by the Board. Judging from the last letter in 1943 from Major Lippincott to Armstrong (seen below), the final report was more than likely not in Roberts favor. But the question remains, did the United States government purchase Roberts claimed invention: the death ray?