Now that this is the second Boeing 737 Max 8 jetliner crash shortly after take off in five months, is there a design flaw or no?

And should all Boeing 737 Max 8 jetliners be grounded?
The Ethiopian Airlines jet that crashed shortly after takeoff on Sunday, killing all 157 people aboard, is the same make and model as the plane that crashed off Indonesia last year with 189 deaths
Officials lost contact with Flight 302, a Boeing 737 Max 8 jetliner flying from Addis Ababa, the Ethiopian capital, to Nairobi, the Kenyan capital, at 8:44 a.m. (1:44 a.m. ET), authorities said.
That was about six minutes after the plane took off from Bole International Airport, they said. Tewolde GebreMariam, the airline's chief executive, said that the captain reported "difficulties" and asked to return to the airport but that then the plane "was lost from the radar - it disappeared."

The Ethiopian Airlines jet had been in service for only four months and had no known technical issues, GebreMariam said.

In late October, Lion Air Flight JT610 - also a Boeing 737 Max 8, which had been in service for only 2½ months - crashed into the sea shortly after takeoff from Jakarta, the Indonesian capital.

Indonesian authorities said that contact with Flight JT610 was lost after 13 minutes and that the captain reported a "flight control problem." Pilots flying the same plane a day earlier had experienced a similar problem, authorities said.

Seems like they may be related as the Lion Air flight was supposedly due to a faulty AoA sensors and MCAS system which was supposed to have been updated, replace faulty sensors and retraining pilots may not have taken place. Some say it is a design flaw but recovery training would help. We've seen other similar crashes in various types where pilots were getting false data from sensors and the automatic systems put planes into a stall or dive. In one case on another style aircraft I recall, the flight controls were able to be operated by both pilots at the same time… No dominance… And both were fighting each other over how to regain control on a dark night over an ocean where no visual references could be used.

As modern planes /controls rely more heavily on sensor data and automatic FBW controls, it seems that pilots need better specific training on what to do to recover from such issues and the 737 Max fleet should be grounded until AoA sensors are tested/fixed, correct any issues with the MCAS and any updated training is performed.

"The report stated based on preliminary findings; it is believed a malfunction in the AoA sensors could lead the on-board computer to believe that the aircraft is stalling, causing it to automatically initiate a dive. The Federal Aviation Administration urged all airlines operating Boeing 737 MAX 8s to heed the warnings.[130] In response to the news of the faulty AoA sensor and the operation of the Maneuvering Characteristics Augmentation System (MCAS), a stall protection system, the FAA issued an emergency Airworthiness Directive (AD) requiring that amended operating limitations and procedures relating to erroneous data from an AoA sensor be inserted into the aircraft flight manual of each 737 MAX aircraft.[131][132]

During difference training, pilots of American Airlines and Southwest Airlines converting from earlier Boeing 737 Next Generation models to the 737 MAX were not informed of the MCAS linked to the fatal crash, leaving them concerned that they were possibly untrained with respect to other differences.[133] In November 2018, Aviation Week reviewed the 737 MAX flight crew operations manual and found that it did not mention the MCAS.[134] American Airlines' Allied Pilots Association and Southwest Airlines Pilots' Association were also caught unaware.[135] The Wall Street Journal reported that Boeing had "decided against disclosing more details to cockpit crews due to concerns about inundating average pilots with too much information".[136]

The CFM International LEAP engines of the 737 MAX have a higher bypass ratio and have a larger nacelle than the engines of previous Boeing 737 models, so the engines are placed higher and further forward in relation to the wing than on previous models. This destabilises the aircraft in pitch at higher angles of attack; to deal with this the MCAS flight control augmentation system is fitted to the 737 MAX.[137] Former Boeing engineers expressed the opinion that a nose down command triggered by a sensor single point of failure is a design flaw if the crew is not prepared, and the FAA was evaluating a fix of the possible flaw and investigating whether the pilots' transition training is adequate.[138]"