By CBSBoston.com Staff

ORLEANS (CBS) — The Coast Guard has suspended its active search for a missing plane off of Cape Cod.

The pilot, who has not been identified, was alone when he left Reading, Pennsylvania Sunday afternoon and was supposed to meet a friend in Chatham Sunday night. The friend contacted authorities about two-and-a-half hours after the pilot was supposed to arrive.

READ MORE: COVID Booster Demand 'Skyrocketing' In Massachusetts

The Coast Guard said it searched for 55 hours in an area covering more than 2,076 square miles “with no sign of missing pilot or aircraft.” The National Transportation Safety Board has opened an investigation into the incident.

“It’s a needle in the haystack, is one of the analogies you can use,” Chatham Harbormaster Stuart Smith told WBZ-TV.

The pilot did not have a flight plan, which is not required for Visual Flight Rules, but recommended when traveling over water or at night.

The Coast Guard searches for a missing plane off Cape Cod (WBZ-TV)

READ MORE: 85-Year-Old Man Killed In Yarmouth Hit-And-Run Crash

Radar picked up the plane over Hyannis and approaching Chatham until it vanished just before 7 p.m., dropping 4,000 feet per minute. Hours passed before authorities could estimate a possible crash location and mount a search.

“That’s a long time,” Smith said. “Hours later in the open ocean, it’s just, it’s a lifetime.”

There were several Coast Guard boats, a helicopter and plane involved in the search. The harbormasters from Chatham, Harwich and Orleans also assisted.

Authorities released pictures of the plane on the remote chance the radar data is misleading, and the pilot landed safely somewhere else.

The Coast Guard is searching for this plane that was traveling to Chatham Sunday but never arrived. (WBZ-TV)

MORE NEWS: Suit Alleges Company Sold Bogus Hand Sanitizer To Massachusetts Schools

The ocean is 60-70 feet deep in the search area.

CBSBoston.com Staff