Thread by @LadyPilotSays

Nothing abt the Titan is worthy of note.

It was hastily & shoddily assembled w/untested materials & eschewed all accepted safety standards for profit.

It's not the world's first submersible. It's nowhere close to the deepest diver.

Let me tell you about the Deepsea Challenger.

Deepsea Challenger (DCV 1) is a 7.3-metre (24 ft) deep-diving Australian-built submersible designed to reach the bottom of Challenger Deep, the deepest-known point on Earth. In 2012 Canadian film director James Cameron piloted it to the bottom of the Mariana Trench, 10,935m deep.

In contrast to the Titan which took a 53cm porthole only guaranteed to withstand pressures to 1,300m down to a depth of 4,000m, every element of the design & construction of DCV1 was thoroughly tested in multiple environments before a single person could pilot it to depth.

You can tell how much engineering went into DCV1's structural integrity & communication capabilities bc despite similarities in total size & volume, the Titan boasts plenty of seating space for 5 adults while DCV1 has room for 1. In the fetal position. The cockpit is 43in wide.

Submersibles need to descend & ascend. Just like a plane, one w/out the other is useless. So finding the right combination of material density which is the most structurally sound while being weight, space, & energy efficient is pretty important. It's also pretty expensive.

The DCV1 puts the pilot in a steel personal sphere at the bottom of the submersible designed & tested to an equivalent full-ocean-depth pressure of 16,500 psi; testing indicated that it could withstand up to 140% of this (23,100psi). At the level of Titanic, pressure is 5850psi.

DCV1 has 3 sections. Roughly 70% of the "beam," the biggest section, is made of syntactic foam, the only flotation material capable of withstanding these crushing pressures. It's composed of glass spheres embedded in an epoxy resin & provides both flotation & structural support.

Being able to withstand hostile temps & pressures once is not enough. Cyclic Ts & Ps material testing is absolutely crucial to success bc at 10,000psi, EVEN STEEL SHRINKS. All materials experience fatigue. You can't have bolts shrink or expand more than what they're bolted into.

DCV1's pilot sphere was tested at Penn State University to 16,500psi where strain gauges attached to the sphere indicated that it could withstand up to 140 percent of the test pressure.

OceanGate, on the other hand, claimed testing of its carbon fibre hull was not possible?!

Contrast that w/DCV1 engineers who tested the two “full-ocean-depth-rated” foams on the market at the time which failed miserably. They cracked, warped, compressed, lost buoyancy, & didn't have nearly the tensile strength required. So lead engineer Ron Allum INVENTED HIS OWN.

I'm not even going to go into the structural details of the ballasts & mechanical operations of DCV1 in this thread (although theyre cool AF & deserve a thread of their own) & I'm going to skim past the structural calamity that is the Titan so I can compare comms & nav equipment.

DCV1 is maneuvered w/joysticks that command 12 thrusters to propel the sub along the ocean floor, 3 knots horizontally & 2.5 knots vertically. Despite its mass, thanks to its 12 thrusters, it's quite agile & can turn on a dime.

The Titan has 4 thrusters controlled by a toy.

Note the glaring lack of redundancy in the Titan's thrusters.

If one vertical thruster fails, you don't have a submersible that can rise, you get a fucking rotisserie.

At every possible safety critical decision, OceanGate chose truly impressive levels of wrong.

>180 systems are monitored & controlled on DCV1, including batteries, thrusters, life support, 3-D cameras, & LED lighting. The pilot can talk to the Mothership Mermaid Sapphire, thru several systems, one w/a 19-mi (30km) range.

The Titan relied on one which consistently failed.

Remember now, James Cameron piloted to the depths of the Mariana Trench, deeper than Everest is tall, & more than double the depth of Titanic, in 2012. ELEVEN YEARS AGO.

Communication failure on the Titan should have been a never event let alone a never again event. And yet...

going back to the thrusters.

The plane I'm learning how to fly on is a Cessna 172P.

My particular learner was built in 1981. It's got a single Lyncoming O-320 5.24L 4 cylinder naturally aspirated engine. I can manually select my magneto if one of the two fails.

Built in 1981.

So a four cylinder 150hp engine can keep humming along with only one magneto driving the sparks.

Lyncoming & Cessna both agreed that equipment failure in a metal tube at 10,000ftAGL would be catastrophic so redundancy was built into the thing that KEEPS THE SPINNY BOI SPINNING.

The level of hubris & frankly criminal, homicidal negligence that every single piece of the Titan exhudes is probably why the folks aboard it are extra dead right now.

Hopefully this will go in the textbooks as an example of what happens when you do literally everything wrong.

Looking at the basic descent & ascent: DCV1 descends because of >450kg of steel weights held to either side by electromagnets. To rise to the surface, the pilot flips a switch, the plates of steel fall to the ocean floor, & the foam pushes the sub skyward. This step is critical.

If the weights don’t drop, the pilot & DCV1 would be stuck at the bottom of the ocean. To ensure they function properly, engineers incorporated not one but SEVERAL backup systems:
1. If there’s a power failure or the magnets’ batteries run out, the weights will drop automatically

2. The support team at the surface can drop the weights via an acoustic command.

3. A special wire (galvanic timed release) helps connect the weights to the sub; it corrodes after ~11-13 hrs in seawater. Even if the pilot is KO'd & mothership can't communicate, the DCV1 rises.

4. The pilot can power up something called a “frangibolt,” which uses heat to break the bolts that keep the weight-drop mechanism in place, thus jettisoning the whole assembly.

FOUR SEPARATE mechanical mechanisms to *guarantee* the DCV1 rises.

Titan had *one* elevator button.

That's four separate mechanical mechanisms as failsafes *IFF* the main switch doesn't work.

Once you see how the Deepsea Challenger's engineers were working on "when X fails..." instead of "*IF* X fails..." you start to recognise how every single mechanism had backups for days.

It just gets worse & worse. Every single element of Titan was living on a prayer. No backups for anything structural. Multiple instances of comms failures that weren't even addressed prior to the next mission. It was guaranteed to fail & frankly a miracle it ever got this far.

Just look at the myriad of ways DCV1 could be found on surfacing:

1. The acoustic navigation system allows the mother ship to track & plot the submersible as it rises through the water column, so the support vessels & divers are in ready attendance (at a safe standoff distance)

2. If this fails, a fully redundant pair of LED beacon lights are visible at night for many miles. These lights run on a dedicated battery system, *fully* separate from the sub’s main power, & can last for up to 16 hrs after return to the surface.

3. There's also a strobe light that can flash for 30 hrs.
4. The sub has TWO separate GPS beacons in separate glass, pressure-resistant spheres. One uses a satellite system to send the sub’s coordinates to the ship’s bridge at any range from the ship. The other uses marine VHF.

Marine VHF (very high frequency) broadcasts DCV1’s coordinates at ranges limited by line of sight: 10km (6mi) for the mothership, & up to 80kms (50 mi) for aircraft.
5. Lastly there is also a Radio Direction Finder system.

The Titan doesn't even have a fucking airtag.

And even if every single component failed on DCV1's surfacing, AT LEAST IT HAD A HATCH

I'm just absolutely in awe of how terrible Titan was. The CEO & builders didn't even bother to cheat off the smart kids in class, they just YOLO'd their way to the bottom of the fucking ocean.

Guys I am not an engineer.

I'm a doctor & a pilot who used to tutor physics *a decade ago*. The extent of my engineering experience was watching my civil engineer father crush pre-stressed concrete as a kid.

And yet these are the Titan failures *I've* identified.

THAT'S MAD.

If anyone knows Ron Allum or any of the Deepsea Challenger engineers please send them my way I have so many questions & I want all their autographs.

Also, if I got anything wrong (more than likely) please let me know.

I'm gonna end here otherwise this thread'll go on forever.

@JimCameron @DeepChallenge

Alright adding to this Titan evidently had multiple different ways to drop ballasts & that the longest it would remain at the ocean floor (assuming it didn't face a catastrophic structure failure & subsequent implosion) was 24 hrs. Unless it was trapped under something else.

If OceanGate was using old scaffolding poles for the ballasts...

None of these catastrophic events occur in a vacuum. Think back to Boeing 777 Max. There are always multiple whistleblowers raising the alarm & being silenced until a very public & often deadly failure occurs.

Just want to reiterate here I'm not an engineer or materials expert. Please do not cite this thread as expertise, it's merely a series of my observations.

For reference, my quals:
• a PADI open water dive license to 18m
• a medical license
• a recreational pilot license

The pain in his voice as he lays out what a disappointment this whole thing has been.

This is not a new art. This is a mature science that was completely disregarded in favour of fame & whose captain met the same fate as the Titanic for the same reason.

That's it folks. An anticlimactic ending to a completely preventable disaster. I'm just glad it was over before anyone one board knew it was starting.

What's particularly interesting is how many libertarians were expecting socialism to save these guys.

bbc.com/news/world-us-…

Indeed at the end of the day, it was several different countries whose tax dollars mobilized regulated units of trained experts to get to the bottom (no pun intended) of this disaster created by folks who notoriously turn their noses up at expertise, regulation & paying tax.

Summary of typos & errors on the DCV1 thread:
1. Lycoming* not Lyncoming Cessna engine
2. Boeing 737 MAX* not 777 Max
3. Ok the Titan *did* have ballast release "backups" but I still wouldn't call "rocking the ship" adequate. Esp when compared to the DCV1's engineered failsafes