"I would FIX the Boeing 737 MAX, add some additional great features, & REBRAND the plane with a new name", Trump said.
One of America's largest airlines is cancelling 115 flights a day because of fears over the safety of the Boeing 737 Max aircraft.
American explained on its website that not all flights previously scheduled on a Max would be cancelled, because the airline plans to substitute other aircraft for some flights.
He added: "No product has suffered like this one".
An Ethiopian Airlines flight crashed minutes after takeoff March 10, killing all 157 people on board. "But again, what the hell do I know?"
The grounding of Boeing Co's fuel-efficient, single-aisle workhorse after two fatal crashes is biting into USA airlines' Northern Hemisphere spring and summer schedules, threatening to disarm them in their seasonal war for profits.
To that, Boeing has responded with a video address by Muilenburg, who acknowledged investigators' findings that it faulty angle of attack sensor input activated Maneuvering Characteristics Augmentation System (MCAS), but retained that multiple reasons played a role in Flight 302 crash.
Almost 400 B737 Max aircraft have been delivered to carriers worldwide, with Southwest now the largest operator with 31 aircraft in its fleet.
The U.S. Federal Aviation Administration grounded the 737 Max on March 13, three days after the second fatal crash involving the jet in five months.
"The FAA is preparing to make an announcement very shortly regarding the new information and physical evidence that we've received from the [Ethiopia crash site] and from other locations and through a couple of other complaints", Trump said.