The executive, W. James McNerney, told analysts that preliminary data “points more in that direction.”
The National Transportation Safety Board issued an interim report on Monday, saying that a laboratory examination of intact sections of the roof found that rivet holes on one layer of the plane’s skin did not line up properly with an underlying layer.
A five-foot hole suddenly ripped open in the cabin roof on April 1, forcing the Southwest jet to make an emergency landing in Arizona.
The safety board did not draw any conclusions about the cause of the rupture, which occurred at 34,000 feet. Independent experts said they were surprised that Boeing’s inspectors had not caught such a basic mistake when the plane was built in the mid-1990s.
Mr. McNerney said federal investigators were still sorting out what happened.
His comments came as Boeing announced that its first-quarter earnings rose 13 percent to $586 million, or 78 cents a share, from $519 million, or 70 cents a share, a year earlier. Revenue slipped 2 percent to $14.9 billion, from $15.2 billion, on weaker revenue in the commercial airplane