SM300-3 Plinio Seniore

Working lease · monthly preferred

Plinio Seniore

SM300-3 · DNV +1A1 Sub III · 300 msw · South Florida

Dry lease · month

$24,500

$8,500 / week · hull, papers, kit

Working wet · month

$92,000

$34,000 / week · plus pilot & surface officer

SubSurface Submersibles

SM300-3 Plinio Seniore

John Antaramian, President & Chief Engineer. The SM300-3 Plinio Seniore is available for hire as a working boat — film, research, tourism, expedition. DNV +1A1 Sub III, 300 msw, South Florida. Triple brand-new oil-packed spare kit travels with the hull.

Monthly is the working term. Dry lease $24,500 a month. Working wet, with a qualified pilot and surface officer, $92,000 a month. Week rates if a short window is required. No purchase price on this sheet — this is a hire programme.

01 — Vessel

Pilot plus two observers. 300 msw.

Yellow work hull. Forward acrylic viewport, low conning position, main and vertical thrusters, keel battery pods. One-atmosphere cabin. Built for film, research, tourism, or expedition.

Plinio Seniore in the water, SM 300/3' and Nuovo Turismo markings

Plinio Seniore in the water, starboard view

Designation: SM300-3
Name: Plinio Seniore
Builder: Global Submarines Oy Ltd
Class: DNV +1A1 Sub III
Depth: 300 msw
Occupancy: 1 pilot + 2 observers
Location: South Florida
Spares: Triple kit, oil-packed

02 — Certification and logs

DNV +1A1 Sub III

Classification file, dive logs, and maintenance history go with the hull. Dates, depths, crew, defects, close-out.

DNV stamp on pressure hull, viewports, and life-support loop.
Operational logs with the boat.
Maintenance history keyed to the triple spare inventory.

Acrylic dome, manifold gauges, battery bank, control panel, and thruster

Looking through the acrylic viewport dome

03 — Triple spare kit

Three of every critical part. Brand new. Oil-packed.

Three complete sets of critical system spares — brand new, oil-packed, drummed, sealed, wax paper. Built for work away from a support shop. The boat ships with the kit.

Pressure hull & hatch
Viewport O-rings, hatch seats, penetrator glands, hull fasteners, anode sets
× 3 SETS · OIL · DRUM · WAX
Ballast & trim
Sea valves, blow circuits, trim-pump rebuilds, strainers, actuator seals
× 3 SETS · OIL · DRUM · WAX
Propulsion
Main and vertical thruster rebuild kits, bearings, props, controllers, glands
× 3 SETS · OIL · DRUM · WAX
Life support
O₂ fittings, CO₂ scrubber charges, sensors, emergency bottles, cabin filters
× 3 SETS · OIL · DRUM · WAX
Electrical
Connector sets, fuses, lighting, battery interconnects, telemetry spares
× 3 SETS · OIL · DRUM · WAX
Hydraulics / pneumatics
Hoses, fittings, accumulators, regulators, preserved in oil
× 3 SETS · OIL · DRUM · WAX

Also here

Deep Ranger · 2-passenger

Yellow project submersible, co-located. Available with the SM300-3 or on its own. Same shop, same readiness.

04 — Working lease

Monthly is the working term. Weekly if you need a short window.

Film, research, tourism, expedition. South Florida handover. The triple kit travels with the boat so a programme is not waiting on a parts order from Europe.

Dry lease

Hull, papers, triple kit

Week: $8,500
Month: $24,500
3 months: $21,000 / mo
6 months: $18,500 / mo

· Hull, DNV papers, and dive logs
· Triple brand-new oil-packed spare kit
· South Florida handover

Not included

· Pilot and surface officer
· Launch and recovery gear
· Fuel, oxygen, Sofnolime
· Mothership P&I and local permits

Working wet

Hull plus pilot and surface officer

Week: $34,000
Month: $92,000
3 months: $78,000 / mo

· Everything in the dry lease
· Qualified pilot
· Surface officer
· Daily ops in South Florida waters

Mobilisation, transport, fuel, oxygen, CO₂ absorbent, and permits billed at cost. P&I stays on the mothership.

05 — Hire comps

What the same class of boat actually charters for

New 3-passenger 300-metre yacht subs charter €60,000–€75,000 per week, crew extra. A U-Boat Worx crewed wet lease starts at €50,000 per month on multi-year 7-pax contracts. The SM300-3 is a used DNV work hull with a complete parts locker. Monthly dry at $24,500 is hull hire. Monthly wet at $92,000 is a working programme with a pilot — still under one week of a new C-Explorer 3.

SM300-3 dry / month

$24,500

Preferred term

SM300-3 wet / month

$92,000

Pilot + surface officer

C-Explorer 3 / week

€75,000

New 3-pax 300 m. Crew extra.

SM300-3 dry leaseMonth
This boat. Hull, DNV papers, triple kit. Lessee supplies launch, recovery, and pilot.
Owner rate card, September 2026
$24,500 / mo
SM300-3 working wetMonth
This boat plus pilot and surface officer. South Florida. Mobilisation extra.
Owner rate card, September 2026
$92,000 / mo
U-Boat Worx wet leaseMonth, multi-year
Crewed package, minimum three months. First public contract is a 7-pax Cruise Sub 7, not a 3-pax work hull.
Marine Industry News, October 2025
from €50,000 / mo
C-Explorer 31 week
New 3-pax / 300 m — same class as the SM300. Crew extra €12,000 / wk.
Pelorus Yachting rate card
€75,000 / wk
C-Explorer 34 weeks
Duration discount on the same new 3-pax 300 m hull. Crew still extra.
Pelorus Yachting rate card
€60,000 / wk
C-Explorer 51 week
5-pax, 200 m. Shallower than the SM300. Crew extra €15,400 / wk.
U-Boat Worx Charter-A-Sub brochure, May 2023
€80,000 / wk
C-Explorer 54 weeks
Duration discount. 5-pax / 200 m.
U-Boat Worx Charter-A-Sub brochure, May 2023
€65,000 / wk
Super Yacht Sub 3 + M/V AlkWeek
New 3-pax / 300 m plus support vessel. Not hull-only.
SUB71 charter listing
from €85,000 / wk
U-Boat Worx charter (Monte Carlo)Week
Published yacht-sub charter band. Prep fee €25,000. Mobilisation extra.
Entropia Monte Carlo
€75,000–90,000 / wk

Contact

John Antaramian

President & Chief Engineer, SubSurface Submersibles · Atlantic Submarines. South Florida. Viewing by arrangement.