THEY’VE lost out on the MH370 finder’s fee of more than $90 million, but underwater exploration company Ocean Infinity is showing no sign of giving up on the lost plane.

Since the official search ended last Tuesday, Norwegian research vessel Seabed Constructor has continued the hunt on its own steam — now looking in previously uncharted areas.

Over the past few days, the ship has been searching an area of the southern Indian Ocean where Chinese navy ship Haixun 01 detected a suspected black box “ping” less than a month after the plane vanished on March 8, 2014.

Seabed Constructor headed north to that spot after the search had already ended on May 29, and their contract with Malaysia was over, after MH370 watchers, including Ireland-based engineer Viv McMahon, suggested they check it out.

On April 5, 2014, the Haixun 01 picked up two separate pulse signals at a latitude of 25 degrees South and 101 degrees East.

There is no definitive proof that the signals came from the missing Boeing 777 but they had the same frequency — 37.5 kilohertz — as those emitted by an aircraft black box.

Around that time, several white objects were also sighted on the ocean surface about 90km away from Haixun 01. Australian authorities were never able to confirm that the signals or the white objects were from MH370.

“What we are trying to do is to use the last two days that we have in the north

area, at the time they thought it (the ping) was a black box,” Ocean Infinity spokesman Mark Antelme told reporters on Friday.

“If we find something, there will be an announcement. I imagine the protocol is to alert the Malaysian authorities, and families will be notified in a sensitive way.”

But those “last two days” have passed and Seabed Constructor has shown no sign of preparing to leave the area.

Last few hours activities in the MH370 search. Two AUV missions started today, after a 29h gap in launches. The end of the search still at least two days away, the length of an AUV mission. pic.twitter.com/Cnr9zZWJQr — Richard Cole (@richard_e_cole) June 3, 2018

Seabed Constructor activities for 24h to 07GMT. 3 AUVs launched in the north (shown in purple) and another launched further north at 10.30GMT. If area of acoustic pings reported by Chinese ship Haixun in 2014 was the target, AUVs launched to date would seem to cover it. pic.twitter.com/7ahXhiH9M9 — Richard Cole (@richard_e_cole) June 1, 2018

Two sources close to the search have told news.com.au that there is talk of Ocean Infinity resuming the search after the treacherous winter months were over.

It is understood that the company will head to Dampier in Western Australia for a commercial job but may return to the southern Indian Ocean to search for the plane towards the end of this year or the beginning 2019.

“I don’t think Ocean Infinity is done here,” one source told news.com.au.

“They really want to put their name on it (finding MH370).”

Despite not receiving a single cent in payment, the whole operation had been a “big PR win for them”, the source said.

Scientists and aviation specialists from around the world have been tracking Seabed Constructor’s progress via satellite since it started scouring the 7th arc on January 21.

The 7th arc is the imaginary line that plots possible locations of the plane at the moment it sent a seventh and last signal to the Inmarsat satellite on the day it disappeared and is located about 2500km from Perth.

And they continue to monitor the ship, a week after Ocean Infinity’s 90-day contract with the Malaysian Government ended with no plane and no multimillion-dollar reward for the company.

#MH370 My morning update. Seabed Constructor moved further north and deployed a couple AUVs meaning they are not going anywhere anytime soon. The northernmost AUV was deployed about 42 NM up arc from the Haixon site. Current position is 25° 27' 37" S 102° 03' 27" E pic.twitter.com/zUeQznkRiY — Kevin Rupp (@LabratSR) June 3, 2018

#MH370 My afternoon update. Seabed Constructor has been chasing AUVs and updating them. They continue to make great progress moving up the arc. The weather is crappy out there with 3.3 meter wave heights and 9.3 KM visibility. Current position is 25° 41' 58" S 101° 50' 59" E pic.twitter.com/piaTtakDqt — Kevin Rupp (@LabratSR) June 3, 2018

#MH370 My night time update. After my last update Seabed Constructor continued up arc and deployed again, about 20 NM north of the Haixon area and then headed south. Perhaps the press will finally figure out that Ocean Infinity isn't ready to stop yet. pic.twitter.com/qr97uKRELw — Kevin Rupp (@LabratSR) June 1, 2018

Observers such as US-based precision machinist Kevin Rupp, London University space scientist Richard Cole and Frankfurt-based British aerospace engineer Richard Godfrey have been faithfully tweeting satellite maps of the vessel’s movements and underwater drone deployments.

Mr Rupp told news.com.au that he believed the ship would stay in the area until at least Friday.

“They’re still actively scanning and covering a lot of area,” he said. “They may not find the wreck but they are going to eliminate an awful lot of theories and sea floor.”

Mr Cole also said it was likely the vessel would remain in the area for several more days, tweeting that autonomous underwater vehicles (AUVs) had been deployed as recently as yesterday.

“Two AUV missions started today, after a 29h gap in launches,” he tweeted overnight. “The end of the search still at least two days away, the length of an AUV mission”.

Ocean Infinity has searched more than 125,000sq km of ocean between about 35 degrees South and 26 degrees South, without finding any sign of the plane’s fuselage or debris.

It stood to earn between $A25 million and $A93 million if it had found the missing plane, but without such a discovery it receives nothing.

The Malaysian Government confirmed it would not extend the search again unless there was credible new evidence of the plane’s location.

Malaysian Transport Minister Anthony Loke Siew Fook said a final report on MH370 would “hopefully” be published in July.

An Ocean Infinity spokesman confirmed to news.com.au the search would likely wrap up on Friday.

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