Until Monday’s disaster, which saw the budget airline’s brand new MAX 8 plunge into the ocean off Indonesia just 13 minutes after take off, killing all 189 on board, the fourth generation 737 was the most sought-after plane in the industry.

But with the cause of the Lion Air crash still unknown, speculation on whether the fault lies with the pilot, Indonesian maintenance crew or the manufacturer itself is mounting.

“The (737 MAX 8) itself is extremely reliable, stronger and more powerful than the earlier 737s,” Australian Aviation magazine publisher and former fighter pilot Christian Boucousis told news.com.au.

“Obviously there was some kind of catastrophic event, but it’s too early in the investigation to say whether it’s an issue with the aircraft, pilot error, a terrorist attack or bomb, or a maintenance fault.

“But it’s a very curious thing. (The crash) happened at a very benign stage of the flight, while the weather was good. It’s unusual.”

Virgin Australia has ordered 30 MAX 8 planes, the first of which are scheduled to arrive in November next year. The company has also ordered 10 Boeing MAX 10s — the fifth and largest variant of the series — which will join the Australian fleet from 2022.

Mr Boucousis said he could understand why some Australians might not want to set foot on a 737 MAX 8 until the cause of the crash is known.

Lion Air flight JT610 had only been in service since August 15 but had performed erratically on at least one occasion prior to the fatal flight, according to customers.

The company is one of Boeing’s biggest clients, forking out $22 billion in 2011 for 201 737 MAX 8 planes.

Lion Air Managing Director Daniel Putut was scheduled to meet with Boeing representatives following an inspection of the company’s 10 remaining MAX 8s earlier on Wednesday.

“Of course there are lots of things we will ask them, we all have question marks here, why? What’s the matter with this new plane?” Mr Putut told AP.

In the wake of the crash, aviators were quick to point the blame at Indonesia, which has a terrible aviation safety record.

Just 10 months ago, pilot fatigue and flight-crew errors caused a near midair collision between another Lion Air flight and a Batik Air jetliner near Surabaya.

Data from Flightradar24 shows flight JT610 struggled from the moment it left Jakarta airport at 6.20am, climbing and falling erratically before plunging 1480 metres in just 21 seconds.

It has since emerged that Lion Air flight JT610 experienced similar issues during a flight from Bali to Jakarta less than 24 hours before its fatal flight on Monday, raising the possibility of mechanical failure.

Passengers on the Sunday flight say soon after take off, the aircraft began climbing and dropping like a rollercoaster, causing several people to vomit and panic. They also took to social media to complain about issues with the airconditioning and cabin lighting.

Aviation specialist Philip Butterworth-Hayes said it was unusual for an aircraft to experience altitude difficulties during take off, which was typically controlled by the plane’s automatic systems.

“This doesn’t fit an automatic flight profile,” he told CNN.

“Unless, the aircraft was trying to correct itself at the time for a number of reasons.”

Mr Butterworth-Hayes said the Flightradar 24 data showed “an unusually unstable vertical flight profile.

“Exactly at the same time as the speed increased there was an altitude dip, which meant that at that point there was quite some loss of control.”

Former US National Transportation Safety Board air crash investigator Peter Goelz said the data clearly showed issues with both the speed and altitude of the plane.

“There is something obviously wrong in both the air speed and the altitude which would point to the flight control systems,” he said. “These are fly-by-wire systems — highly automated — and pilots may not be able to troubleshoot failures in a timely manner.”

Mr Boucousis said he had heard “many rumours and theories” about what may have caused the crash but said the truth could not be known until the plane’s black boxes — the cockpit voice recorder (CVR) and the flight data recorder (FDR) — were recovered.

“It’s unlikely to be an MH370 type situation because the plane went down in about 30m of water so hopefully the CVR and the FDR can be retrieved and we can find out what happened in those 13 minutes between taking off and crashing into the ocean.”

This afternoon Indonesian authorities announced the discovery of the plane’s fuselage in the waters of Tanjung Karawang, 15 nautical miles from the area where the plane lost contact.

Boeing acknowledged the find and said it was ready to provide technical assistance to investigators but directed all inquiries to Indonesian authorities.

“The Boeing Company is deeply saddened by the loss of Flight JT 610. We express our concern for those on board and extend heartfelt sympathies to their families and loved ones,” it said in a statement.

“Boeing stands ready to provide technical assistance to the accident investigation.”

Virgin Australia said it would monitor developments ahead of the scheduled arrival of its first 737 MAX 8s in November next year.

“We will continue to monitor the outcome of the Lion Air incident and should any recommendations come out of that investigation, Virgin Australia would be fully compliant with implementing these recommendations,” it said in a statement.

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