A pair of fatal crashes of Boeing 737 Max 8 jets in about four months has punished the airplane maker’s stock and drawn criticism from President Donald Trump on Tuesday.

‘OLD AND SIMPLER IS FAR BETTER’

In a multipart tweet that didn’t specifically mention Boeing Co. BA, -2.31% or a Sunday crash of 737 Max 8 jet near Addis Ababa that left 157 people dead, the president said: “Airplanes are becoming far too complex to fly. Pilots are no longer needed, but rather computer scientists from MIT. I see it all the time in many products.”

He continued: “Always seeking to go one unnecessary step further, when often old and simpler is far better. Split second decisions are needed, and the complexity creates danger.”

Trump’s tweet comes as aviation regulators across the globe have taken the unusual step of grounding the 737 Max jets on the heels of the weekend Ethiopian Airlines crash, even after the U.S. Federal Aviation Administration declared the planes airworthy.

Read:Boeing’s 737 Max jet has now been grounded by these countries

The crash in Ethiopia came after a 737 Max 8 in Indonesia, operated by Lion Air, fatally crashed in the Java Sea back in October.

Although no cause or link between the fatal plane incidents have been gleaned, the fact that the model plane is new, released in 2017, and features new flight technology, has raised questions among experts.

On Tuesday, Boeing it doesn’t have “any basis to issue new guidance to operators.”

NBC News reported that Trump had a conversation with Boeing’s CEO Dennis Muilenburg on Tuesday about the fatal Ethiopian crash.

Boeing’s shares have been under heavy pressure in the wake of the crashes, down 5.4% on Tuesday after declining by about that much a day ago.

The company holds a significant place on Wall Street and Washington; it is the maker of Air Force One, which is a highly customized model 747-200B, and it is the most influential component of the Dow Jones Industrial Average DJIA, -1.34% .

Over the past year, Boeing’s shares have gained 16.4%, outperforming the broader market, with the S&P 500 index up by about 11.4% in 2019 so far and the Dow rising 9.6%, according to FactSet data.

Boeing’s stock had been the best performer among the Dow’s 30 components, up about 24%, until the past two sessions.

CONSERVATION BILL AND GREENPEACE TWEET

Trump signed a bill named for the late Rep. John Dingell that protects millions of acres of land from future mining operations and expands Joshua Tree and Death Valley national parks. Michigan Democrat Dingell died in February at age 92.

Separately, Trump tweeted a quote by Patrick Moore — who the president claimed was co-founder of Greenpeace — that said the “climate crisis” was “Fake Science.” The environmental group says that Moore played a role in Greenpeace Canada but didn't co-found Greenpeace and doesn’t represent it.

Now read:Ocasio-Cortez dismissed as a ‘garden-variety hypocrite’ — and worse — by former Greenpeace Canada president.