The crash Sunday morning of a jetliner in Ethiopia bears unmistakable similarities to the Oct. 29 tragedy off the coast of Indonesia involving the same model, prompting questions about whether a design issue that arose during the earlier accident could be to blame. It is the second fatal crash of a Boeing 737 MAX aircraft in six months.

Experts urged caution about drawing conclusions too quickly, although details of the crashes – shortly after takeoff, at relatively low altitudes with erratic flight patterns – seem similar, the data are insufficient to conclude that the same systems were at fault.

The Indonesian Lion Air Plane air crash report found that a sensor measuring the plane’s “angle of attack” fed erroneous data into the plane’s flight control system, at which point an automatic feature kicked in, sending the plane into a nose dive. The problem lies with “angle of attack” sensors that measure the wind speed over an aircraft’s wings, according to the Boeing notification. Their measurements are meant to detect if a plane is moving too slowly, which can cause it to lose control. The Lion Air plane lost altitude dozens of times before it crashed as the jet’s computers, thinking it was in danger of losing control, continually tried to push down its nose. The pilots countermanded the aircraft’s software over and over, pulling it back into climbs, until they failed to do so and it crashed.

The report stopped short of assigning blame for the crash. However, multiple pilots organizations in the United States criticized Boeing after it disclosed that it had made certain changes to the MAX’s autopilot software – it added a new flight-control feature, the Maneuvering Characteristics Augmentation System (MCAS). The updated software was meant to account for design changes to the 737 MAX, and was supposed to make the plane operate as closely as possible to older 737 models despite having larger engines placed farther forward on the plane’s wings. While the MCAS system was ostensibly added to make the plane safer, pilot unions in the United States said they had been left “in the dark” about the software update and criticised Boeing for failing to cover the new system in training sessions.

If the results of an inspection turn up significant design flaws in the 737 MAX, planes could be grounded worldwide. Six Boeing 737 Maxs are in use in India —five by Jet Airways and one by SpiceJet. The two airlines have also placed orders for over 200. Following Boeing’s circular, India’s civil aviation regulator, the Directorate General of Civil Aviation (DGCA) has asked Jet Airways and SpiceJet to address any issues with their 737 Max aircraft.

After the Ethiopian crash, Only China has so far grounded similar aircrafts: China’s aviation regulator had ordered Chinese airlines, which has 96 737 MAX jets in service, to suspend the operations.

The 737 MAX 8, which was expected to significantly improve the fuel efficiency, has been a major profit driver for Boeing since it was introduced in 2017, and it is critical to Boeing’s broader international ambitions as it competes with Airbus, its European rival in the commercial airline business. Boeing has delivered 354 of the jets globally and has another 2,912 on order. The jet that crashed Sunday was one of five 737 MAX 8 planes operated by Ethiopian Airlines, which has 25 more on order. In the United States, Southwest Airlines and American Airlines have 59 between their two fleets, with 304 on order.

Why should the regulators and the designers soft pedal the Lion Air crash analysis that could have led to a ‘repeat’ incident? Whether commercial interests camouflage the passenger safety?