While the world of underwater exploration is still considered a quiet one there are those who still strive to push the envelope and go further, deeper and longer than others have.

Mans fascination with going underwater in vessels is nothing new. Jules Verne books were rich in telling tales of undersea adventure. One craft - The Nautilus, being a hallmark.

Outside of the state-sponsored navies is the civilian world of underwater craft.  It's a fledgling one requiring hefty investment.

Made up of wealthy entrepreneurs and mavericks they contribute a great deal to this niche activity.
Recently though at least one company has developed a commercially-built underwater craft.

Listed below is an example of one of the craft made by an underwater pioneer using cutting-edge technology.

The Mantis Submersible

The Mantis Submersible was made famous in the James Bond film 'For your eyes only'

Equipped with two manipulator arms it made an impression on audiences.

The above craft is named 'Deep Flight I' and was built around 1995.

Over a decade later the world of underwater adventuring has moved further into developing and refining the art of underwater piloting of these craft. It is notable for being the fastest craft of it's class.

Specs:

Crew: One person, prone position
Life Support: 18 Hours
Flight Endurance: 1-4 Hours

Dimensions: 13 ft. long, 8 ft. wide, 3 ft. high
Weight: 2,860 pounds
Operational Depth: 3,300 fsw
Speed: Max: 12 knots (estimated). Cruise: 4-8 knots. Minimum: 2 knots

Construction: Glass/Epoxy composite (main structure)
Ascent Rate: 650 feet/minute
Descent Rate: 480 feet/minute
Attitude / Roll Range: Through 360 degrees

Deep Flight 2

Deep flight 2 is still in the development stage and is awaiting funding to move into the prototype stage.

Life Support: 96 Hours
Flight Endurance: 8 Hours
Dimensions: 16 ft. long, 9 ft. wide, 4 ft. high
Weight: Est. 5000 lbs. single person config.
Operational Depth: 4,000/20,000/37,000 fsw
Speed: 6 knots
Construction: Ceramics (US Navy)
Ascent Rate: 700 feet/minute
Descent Rate: 400 feet/minute
Pitch: +/- 60 degrees
Roll: +/- 60 degrees

Deep Flight Challenger

A more up-to-date underwater craft. It's slow speed inhibits it, but it's tough construction and range make up for it.

Capable of 37,000 feet its record breaking attempt is currently in limbo as it's pilot died in a plane accident.

Specs:

Life support: 24 hours
Flight endurance: full ocean depth and back in 5 hours

Dimensions: Length 17 ft 8 inches, Width 12 ft 11 inches, Height 5 ft, 7 inches
Weight: 4730 lbs

Speed: Cruise – 2.2 knots; Max – 3 knots
Ascent/Descent Rate:350 feet/second at +/- 45 degrees
Operating Depth: 37,000 fsw
Crew: 1

The latest underwater craft, still in the prototype stages, little is known about it so far.

Specs:

Unknown.

Scubacraft

  Although it requires scuba equipment to breath independently the pilot of this craft can reach 50 mph at the surface then descend to a dive site or area. Uniquely for all underwater craft reviewed so far, it requires no boat to carry it and lower it below sea level. It can independently travel for miles prior to descending. Making it a versatile craft.

It is in commercial production, making the transition from project-built to made-to-order

Max Power: 160 hp

Dimensions: Length 4.5 metres. Width 2.1 metres. Height 1.8 metres
Weight: 390 Kg

Speed: (Surface) Cruise - 18 knots Max – 45 knots
Speed: (Sub-Sea) Cruise - 1-2 knots Max - 3 knots
Surface Range: 100 miles
Sub-Sea Range: Variable. Battery life is 90 minutes. Recharged from onshore location.
On-board recharge system in development.

Ascent/Descent Rate: 350 feet/second at +/- 45 degrees
Compressed Air: 4200 litres (3 x 7l @200 bar)
Operating Depth: 100 fsw
Crew: 3

Propulsion: Prop-driven Environmentally sealed DOHC 4-stroke engine (surface).
2 x 24V Lithium Batteries (sub-surface).

Estimated cost: Undisclosed but believed to be in excess of $160,000.