Pilgrim Nuclear Plant, 2015: A 'Drone' Nobody Could Identify

What this record is

“Pilgrim Drone Spotting” is a short chain of Nuclear Regulatory Commission emails from 29 September to 1 October 2015. The participants are Brett Klukan, the regional counsel in the NRC’s Region I office, which oversees plants in the Northeast; Raymond Lorson; and staff members Anthony Dimitriadis, John Cherubini and Dana Caron. The subject is a possible drone sighting at the Pilgrim Nuclear Power Station in Plymouth, Massachusetts. The seven-page PDF repeats the same few messages several times, as email printouts do. The exact date of the sighting is not given, only that it happened shortly before the first message.

The record appears to be one of the three NRC documents the National Archives released on 24 April 2025, the first NRC transfer to the UAP collection.

What it says

Late on 29 September 2015 Klukan asked Lorson what had happened with “that” and whether the plant had eventually filed a report. Lorson replied the next morning that, the last he had heard, the licensee “wasn’t sure if the flyover was a bird, plane, drone or superman,” and asked whether anyone had heard back from Pilgrim. Caron said the last word was that it might have been a weather balloon and that she would ask the plant’s security manager. Lorson answered that “the air force said that a lot in the 50s as you may recall.”

On 1 October Caron reported what the security manager told her. Plymouth police had come to the site and found that the object was much higher than first thought, “thousands of feet,” and could not be made out at that distance. The FAA was contacted “to no avail.” Massachusetts State Police sent a helicopter, but its crew could not identify the object either. The consensus was that it might have been a weather balloon of some kind, “but no one was definite. They are calling it a UFO.” It posed no threat to the plant because of its distance and was not “indicative of any kind of surveillance or suspicious activity” that would have met the criteria for a report to the NRC’s Suspicious Incident Database, so none was filed. “That should close this episode out,” she wrote.

Lorson had the last word: “For the record we don’t regulate UFOs so I assume no need for additional action.”

Context

In 2015 small drones were just becoming a routine worry for nuclear security, and plant guards had no reliable way to tell a small drone nearby from a larger object far away. This episode shows that uncertainty plainly. What began as a possible drone over the site ended as something thousands of feet up that a police helicopter could not identify, and so something the NRC had no rule for. The plant decided it did not meet the reporting threshold, which at that time applied to voluntary suspicious-activity reports, and the regulator agreed.

The joke in Lorson’s reply is the same gap a later NRC security specialist tried to close. In 2023, after Congress required the NRC to help count “unidentified anomalous phenomena or drones of unknown origin” at nuclear sites, Daryl Johnson argued that anything licensees could not classify was being filed as a drone or not filed at all. The documents from that debate are covered on the page about the NRC’s UAP flyover reporting policy. The Pilgrim emails are an early example of what he was describing: an unidentified object over a nuclear plant that left no trace in the regulator’s incident data.

Pilgrim, a single-reactor plant on Cape Cod Bay, shut down permanently in 2019. Other reports of lights over nuclear sites on this site include the Indian Point hover of 1984.

Status

The object was never identified. The most specific explanation offered, a weather balloon, was a guess that no one was willing to confirm, although a high-altitude balloon would fit an object too high and too small to make out, even from a helicopter. The plant judged it no threat, filed no incident report and the NRC took no action. The record shows a regulator’s routine, slightly amused handling of something it had no category for. It does not show that anything unusual was over Plymouth.

Sources

• National Archives catalog, “Pilgrim Drone Spotting”: https://catalog.archives.gov/id/488808329
• File: https://catalog.archives.gov/medialz/electronic-records/rg-615/488808322/Klukan_Oct_2015_Emails_re_Pilgrim_Drone_Spotting.pdf
• Series: Records from the Nuclear Regulatory Commission Relating to Unidentified Anomalous Phenomena: https://catalog.archives.gov/id/488808322
• National Archives press release, 24 April 2025: https://www.archives.gov/press/press-releases/2025/nr25-07
• HM05 UAP, “National Archives UAP record uploads” (the three NRC documents released in April 2025): https://hm05uap.substack.com/p/national-archives-uap-record-uploads