Washington(CNN) Add modern aviation technology to the list of technological advances the President of the United States distrusts.
"Airplanes are becoming far too complex to fly," President Donald Trump tweeted on Tuesday. "Pilots are no longer needed, but rather computer scientists from MIT. I see it all the time in many products. 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. All this cost for very little gain."
Trump's tweets come days after a Boeing 737 MAX 8 plane crashed, the second time in months that the new airplane model has wrecked minutes after takeoff, killing all on board. The crashes have raised questions about the role of a new software system installed on the plane, but investigators have yet to reach a conclusion about the cause.
The similar circumstances of both crashes have caused several countries and airlines to ground the 737 MAX 8 planes, but despite growing calls from US lawmakers to do the same -- and Trump's tweet on Tuesday morning -- the Federal Aviation Administration has yet to follow suit.
Trump and Boeing CEO Dennis Muilenburg spoke by phone on Tuesday after Trump's tweet, according to two sources familiar with the call, in the first known conversation between the Boeing CEO and the President since the Ethiopian Airlines plane crash on Sunday. The sources did not share details of their conversation.
Trump's tweet, though, cast aspersions on more than just the 737 MAX 8's potentially faulty new anti-stall system that may have caused the nose of both planes to erroneously and fatally dip downwards. He's calling into question the broad spectrum of sweeping technological advances that have made airplanes much safer in recent decades.
And it's not the first time the septuagenarian has cast a skeptical eye on technology.
"I think that computers have complicated lives very greatly," then-President-elect Trump said in December 2016, addressing reporters from his Mar-a-Lago retreat in Florida. "The whole age of computer has made it where nobody knows exactly what's going on. We have speed -- we have a lot of other things, but I'm not sure we have the kind the security we need."
Trump has also expressed a mistrust and dislike of email.
"I'm not an email person," Trump said during a July 2016 news conference in which he invited Russia to uncover and release Democratic rival Hillary Clinton's deleted emails. "I don't believe in it because I think it can be hacked, for one thing. But when I send an email -- if I send one -- I send one almost never. I'm just not a believer in email."
But Trump's latest tech-fueled skepticism -- about airplane technology -- comes despite the fact that he has been a consistent booster of the biggest US airplane manufacturer, which produced the 737 MAX 8: Boeing.
Boeing has been at the center of several of the commercial deals Trump has ceremonially brokered during his foreign trips, most recently during his trip to Vietnam last month where he oversaw the sale of 100 Boeing 737 MAX planes -- 20 of those MAX 8 models -- for $12.7 billion. Vietnam's Civil Aviation Authority announced on Monday that it will "not be reviewing licenses for the use of Boeing 737 MAX planes until the causes for the crashes are identified."
What's more, acting Defense Secretary Patrick Shanahan was a top Boeing executive during the development and release of the 737 MAX planes.
He described feeling a "balance of anxiety and excitement" as he watched the first flight of a 737 MAX in 2016, suggesting he was closely involved in its production.
"It's no different from the birth of a child," Shanahan told GeekWire then. "Now we want to do it about 10,000 more times."
Trump told friends and allies last month that he was leaning toward nominating Shanahan to formally take over as secretary of defense, but has yet to do so.