An initial federal investigation has revealed the home-built plane that crashed in Long Island Sound last week went down last Sunday night, roughly 14 hours before it was first discovered floating off Mattituck.
The cause of the fatal crash that killed 41-year-old pilot Zubair Khan has not yet been determined, investigators said.
The preliminary report issued by the National Transportation Safety Board Tuesday found that Mr. Khan took off in his experimental single-engine aircraft from Brookhaven Calabro Airport about 6:55 p.m. last Sunday.
The plane turned north from the airport and climbed to about 8,500 feet as it flew over the shoreline, according to the report. About 7:04 p.m., radar spotted the plane making a hard left turn and descending to about 5,800 feet.
About a minute later, according to the report, the plane was picked up on radar just 1,100 feet above sea level. That was the last sign of the craft on radar, the report found.
Investigators found that the plane left in good conditions for visual flying and did not file a flight plan.
Mr. Khan’s family said last week that it was concerned the crash was not reported until Monday even though Mr. Khan had departed the airport the day before. His brother-in-law, Umar Niazi, questioned why a search and rescue effort wasn’t conducted Sunday evening.
“This all seems very strange,” Mr. Niazi wrote in an email.
A spokesman for the Federal Aviation Administration said Brookhaven’s airport is “non-towered,” meaning there is no control tower coordinating flights.
It’s common for smaller planes to take off and land at these airports without notifying authorities, the spokesman said.
“As long as you can fly and see what’s ahead of you … those flights take place all the time,” he said. “There’s really no way of knowing how many of those aircraft are flying at any one time.”
NTSB investigators said Mr. Khan was fatally injured in the crash and was found inside the plane Monday morning, with a personal parachute pack deployed and still attached.
The plane suffered “substantial damage” to its fuselage and nose, the report states. Edges of the plane’s left wingtip and right canard were also damaged. The canopy was missing from the craft, and investigators found no sign of “tearing or shearing” of the bolts; however, the report notes that the bolts were missing from the craft.
NTSB investigator Shawn Etcher said the canopy was found three days after the crash floating about 39 miles northeast near Westerly, R.I.
Mr. Etcher said a mount for a video camera was found on the recovered canopy, but there was no sign of a camera on the recovered hatch.
On Monday, a boater discovered a video camera which may be related to the crash, he said.
“It is currently being prepared to be sent to our laboratory for examination and possible download to determine if it was part of the airplane,” Mr. Etcher said.
The victim’s brother-in-law had said Mr. Khan recorded “every moment of his flying” with a camera installed in the cockpit of his plane. Mr. Khan had posted videos of some of his initial flights on YouTube.
The full investigation into the cause of the accident is expected to take between three and 12 months to complete, Mr. Etcher said.
Correction: An earlier version of this story misspelled Brookhaven Calabro Airport.