WASHINGTON – President Donald Trump weighed in Tuesday on the crashes of a new Boeing jet model by claiming that "airplanes are becoming far too complex to fly" and may be too susceptible to crashes.

In a tweet two days after the crash of an Ethiopian Airlines jet made by Boeing, the second such accident in five months, Trump tweeted that "pilots are no longer needed, but rather computer scientists from MIT," and manufacturers are "always seeking to go one unnecessary step further, when often old and simpler is far better."

While not proposing any alternatives, Trump claimed that "complexity creates danger," and added: "I don’t know about you, but I don’t want Albert Einstein to be my pilot. I want great flying professionals that are allowed to easily and quickly take control of a plane!"

Boeing 737:UK becomes latest to ground Boeing 737 Max 8 jets after Ethiopian Airlines crash

The cause of the Ethiopian Airlines crash that killed all 157 passengers on Sunday has yet to be determined.

More than two dozen airlines around the world have grounded planes.

Sara Nelson, president of the Association of Flight Attendants, tweeted Tuesday that technology has made aviation safer through collaboration between manufacturers and crews. Nelson added that "mindless blurbs" from "someone who should know better don't help."

Crash investigators in Ethiopia and Indonesia are studying two fatal crashes in five months involving a new version of Boeing’s 737 called the Max 8.

The design of the engines prompted Boeing to change software for how the plane behaves, which risks exacerbating a dive if pilots aren’t familiar with the change.

Boeing issued additional instructions for dealing with the change after the Indonesia crash and repeated the warning after the Ethiopia crash Sunday.

Will the US ground Boeing 737 Max 8 jets:Questions following Ethiopian Airlines crash left unanswered

While the causes of both crashes remain under investigation, several countries have grounded the 737 Max 8, although not the United States.

Sens. Mitt Romney, R-Utah, and Elizabeth Warren, D-Mass., called on the FAA to ground the Max 8 on Tuesday.

"Out of an abundance of caution for the flying public, the @FAANews should ground the 737 MAX 8 until we investigate the causes of recent crashes," tweeted Romney.

Warren, in a statement, said while the causes of the crashes are unknown, "serious questions have been raised about whether these planes were pressed into service without additional pilot training in order to save money."

Trump's comments came shortly after the United Kingdom became the latest country to ground Boeing 737 MAX 8 planes, the U.S. company's hottest-selling model.

Trump's analysis of airplane problems drew ridicule from his critics.

"Hard to believe this guy bankrupted an airline," tweeted Cody Keenan, a speechwriter for President Barack Obama.