One video recording don reveal di moment wey Oceangate Titan submersible bin loss inside di ocean before e implode.

Na di support ship for di submersible bin record di video and di communication wey happun before e implode.

Di Titan bin implode about 90 minutes afta e enta to see di wreck of di Titanic for June 2023, and e kill all di five pipo on board.

Di passengers bin pay Oceangate to see di ship, wey dey 3,800m down.

Di pipo wey bin dey on board na Oceangate CEO Stockton Rush, British explorer Hamish Harding, veteran French diver Paul Henri Nargeolet, di British-Pakistani businessman Shahzada Dawood and im 19-year-old son Suleman.

Di BBC don get a path breaking access to di US Coast Guard (USCG) investigation for a documentary, Implosion: The Titanic Sub Disaster.

Di USCG recently obtain di video recording USCG and e show Wendy Rush, di wife of Mr Rush, dey hear di sound of di implosion wen she bin dey watch am from di submersible support ship. She ask: "Wetin be dat bang?"

Dem don present di video as evidence to di USCG Marine Board of Investigation, wey don spend di last two years to chook eye into di catastrophic failure of di submersible.

Di documentary also reveal di carbon fibre wey dem bin use build di submersible as e start to break apart a year before di fatal dive.

Titan support ship bin dey wit di submersible wen e bin dey dive into di Atlantic Ocean.

Di video show as Mrs Rush, wey be di director of Oceangate wit her husband, sidon in front of computer wey bin dey send and receive text messages from Titan.

Wen di sub reach a depth of about 3,300m, dem hear noise wey sound like say door bin dey bang.

For di video dem see as Mrs Rush pause and den look up and ask oda Oceangate crew members wetin di noise be.

Within moments she den receive a text message from di sub wey say e don drop two weights, wey be like say e bin lead her to mistakenly tink say di dive bin dey proceed as expected.

Di USCG say di noise na infact di sound of di Titan wen e bin dey implode. However, di text message, wey be like say dem send am just before di sub fail, bin take longer to reach di ship dan di sound of di implosion.

All five pipo wey bin dey on board di Titan die instantly.

Before di fatal dive, deep sea experts and some former Oceangate employees bin don raise warnings about di Titan design.

One of dem bin describe am as an "abomination" and say dem no go fit avoid di disaster wey dey wait to happun.

Titan bin neva undergo any independent safety assessment, known as certification, and one key concern na say e dey hull - di main body of di sub wia di passengers bin siddon - dem bin make am of layers of carbon fibre mixed with resin.

Di USCG say dem don identify di moment wey di hull bin start to fail.

Carbon fibre na highly unusual material for a deep sea submersible sake of say e dey unreliable under pressure.

One problem wey dem sabi about am na di layers of carbon fibre wey fit separate, a process called delamination.

Di USCG beliv say di carbon fibre layers of di hull bin started to break apart during one dive to di Titanic, wey bin happun a year before di disaster - di 80th dive wey di Titan don make.

Passengers on board bin report say dem hear a loud bang as di submersible bin dey try to go back to di surface.

Dem say at dat time Mr Rush bin say dis noise na di submersible wey dey shift e frame.

But di USCG says di data wey dem bin collect from sensors wey dem put for di Titan show say na di separation (delamination) of di layers of di submersible bin cause di bang.

"Delamination at dive 80 was di beginning of di end," na wetin Lieutenant Commander Katie Williams from USCG tok.

"And evribody wey enta or dey onboard di Titan afta dive 80 bin dey risk dia life."

Titan bin carry passengers on three more dives for di summer of 2022 - two to di Titanic and one to a nearby reef, before e fail on di next deep dive, for June 2023.

Businessman Oisin Fanning bin dey onboard di Titan for di last two dives before di disaster.

"If you dey ask a simple question: 'Weda I go again afta I don sabi wetin I know now?' - di answer na no," im bin tell di BBC News.

"A lot of pipo no go want go. Very intelligent pipo wey lose dia lives, wey, like say dem bin get all di facts, dem for no male dat journey."

Deep sea explorer Victor Vescovo say im bin get serious negatives about Titan and say im bin don tell pipo say diving wit di submersible be like playing Russian roulette.

"I bin don warn pipo to stay away from getting into dat submersible. I bin specifically tell dem say na a mata of time before e go fail catastrophically. I bin tell Stockton Rush imsef say na wetin I beliv."

Afta di sub imploded, dem discover di destroyed wreckage wey scata across di sea floor of di Atlantic.

Di USCG bin describe di process of searching through di recovered debris - im bin tok say dem find clothing from Mr Rush, as well as business cards and stickers of di Titanic.

Later dis year, di US Coast Guard go publish di final report of di findings from di investigation, wey aim to establish wetin bin go wrong to prevent a disaster like dis make e no happun again.

Speaking to di BBC documentary team, Christine Dawood, wey lose her husband Shahzada and son Suleman for di disaster, tok say e don change her forever.

"I no tink say anybody wey go through loss and dis kain trauma fit ever be di same," she tok.

Di ripples from di Oceangate disaster dey likely to kontinu for years - dem don already file some private lawsuits and criminal prosecutions fit follow.

Oceangate bin tell di BBC: "We again offer our deepest condolences to di families of di pipo wey die on June 18, 2023, and to all di impacted by di tragic accident.

"Since di tragedy happun, Oceangate permanently close down dia operations and focuse dia resources on fully cooperating wit di investigations.

E go dey inappropriate to respond further while we dey wait for di report from di agencies'."