The Republican said the missing plane could have landed somewhere as part of terror scheme.
Dianne Feinstein is citing personal experience in a call for regulation of unmanned aircraft.
The leading airport for flight trouble is Washington’s Ronald Reagan National.
"There is still investigation to be had," he said.
King said the pilot and the co-pilot “should have been the focus from the start.”
"I think this all leads toward the cockpit,” the Texas Republican said.
Twenty-five countries are now involved in the search as speculation turns to pilots.
Critics say the two-year-old deal hasn't worked, which the Obama administration disputes.
Malaysia’s prime minister said missing airplane was deliberately diverted.
"In many ways we're back where we started," said Rep. Peter King.