1999 Mainship 430 Aft Cabin 3SR
Powered by twin Caterpillar 350 HP engines, she also features a Kohler 8 kW generator, oil change system, dripless shaft seals, and a Weaver tender davit system—ensuring convenience and ease of maintenance. The flybridge is expansive, protected by a bimini and isinglass enclosure, and perfect for entertaining or navigating in comfort.
Additional highlights include an AB aluminum RIB tender with a 9.9 HP Yamaha outboard and an upgraded Garmin electronics suite. A veteran of the Great Loop, THIS Is What is a proven performer—well-equipped, reliable, and ready for her next adventure.
Recent upgrades and maintenance includes:
2025
-Upper helm Isinglass replaced
-Salon bottom cushions reupholstered
-Salon, galley and lower helm hardwood floor refinished
2024
-New 4 blade propellers 24x18
-Upgraded Vacuflush generator
-New Forward MarinAire 9,000 BTU air conditioner
-Upper helm cushions reupholstered
2023
-Garmin AIS800 installed
-VHF radio installed
-New Vitrifrigo refrigerator
2022
-150' G4 5/16" anchor chain
-Garmin GPSMAP multi-purpose display installed
-Garmin Fantom 1 radar installed
-Pepwave internet router with WiFi installed
2021
-Garmin ECHOMAP plotter
-Engine Fire Suppression system
-Mast Hinged
2019
-AB Hypalon Aluminum RIB tender
-Yamaha 9.9 HP outboard
-Delta Anchor 44 lbs
Basic Boat Info
Boat Name: THIS Is What
Make: Mainship
Model: 430 Aft Cabin 3SR
Year: 1999
Condition: Used
Category: Power
Construction: Fiberglass
Boat Hull ID: MPTSM010D999
Has Hull ID: Yes
Keel Type: Other Keel
Dimensions
Length: 43 ft
Length Overall: 43 ft
Beam: 15'6 ft
Max Draft: 3'8 ft
Bridge Clearance: 18'1 ft
Cabins Count: 3
Engines / Speed
Engines: 2
Engine #1 Specs:
-Make: Caterpillar
-Model: 3116
-Fuel: Diesel
-Engine Power: 350hp
-Type: Inboard
-Drive Type: Direct
-Engine Hours: 4,073
Engine #2 Specs:
-Make: Caterpillar
-Model: 3116
-Fuel: Diesel
-Engine Power: 350hp
-Type: Inboard
-Engine Hours: 4,073
Total Engine Power: 700 hp
Cruising Speed: 15 kn
Maximum Speed: 18 kn
Tanks
Fuel Tank Capacity: 500 gal
Water Tank Capacity: 250 gal
Holding Tank Capacity: 50 gal
Other
Heads Count: 2
Drive Type: Direct
Boat Class: Trawlers, Aft Cabin, Flybridge
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- Additional information
- ***Mainship 430 Aft Cabin Vessel Walk Through***
Boarding THIS Is What from the swim platform, you enter through the transom door into the cockpit. From here, you can either proceed forward along the wide side decks or step directly down into the master stateroom via its private access door. Both side decks lead to molded-in steps that take you up to the aft deck, with convenient access to port and starboard side walkways and the foredeck.
From the aft deck, additional molded steps lead up to the spacious flybridge or into the salon through the sliding aft door.
Inside the salon, you'll find a comfortable and well-designed living space. To port is a large U-shaped settee surrounding a hardwood dinette table, while the port forward section houses the fully equipped, dual-sided galley. To starboard forward is the lower helm station, just aft of which sits a full-size refrigerator and flat-screen TV. Starboard aft features a built-in desk with two folding teak chairs and cushions, providing a versatile work or relaxation space.
Moving forward and down a few steps, you'll find the guest head with a separate enclosed shower to starboard and the midship guest stateroom to port. The forward guest stateroom is located in the bow, while the master stateroom—complete with an ensuite head—is located aft and can be accessed from either the salon or the cockpit.
The engine room is easily accessed through a hatch in the salon sole or via the lift-up steps leading to the forward berthing area.
***Mainship 430 Aft Cabin Accommodations***
THIS Is What offers a spacious, full-beam master stateroom aft, featuring a queen-size island berth and a private ensuite head with a separate enclosed shower for added comfort and convenience.
Forward, the guest stateroom in the bow includes a V-berth with a filler cushion to create a double berth. Just aft and to port is the midship guest stateroom, which offers two single berths—perfect for additional guests or crew.
The guest head is located to starboard, just aft of the forward stateroom, and also features a separate enclosed shower.
***Mainship 430 Aft Cabin Salon***
The salon aboard THIS Is What offers a warm, inviting, and highly functional layout. To port, a large U-shaped settee provides comfortable seating with ample storage beneath the cushions. On the starboard side, a built-in desk occupies the aft corner, accompanied by two folding teak chairs with cushions. A flat-screen TV is mounted on the aft side of the refrigerator cabinet, perfectly positioned for easy viewing.
Forward on the starboard side, you’ll find the large refrigerator and the lower helm station—both thoughtfully integrated for convenience and functionality.
From the salon, you have direct access to the master stateroom, aft deck, galley, engine room companionway, midship guest stateroom, guest head, and the forward guest stateroom—making this central space a true hub of the vessel.
Large opening side windows and a forward windshield flood the space with natural light and provide excellent ventilation. The teak and holly sole, complemented by rich hardwood trim, adds a classic nautical elegance to this beautifully designed interior.
***Mainship 430 Aft Cabin Galley***
The fully equipped, dual-sided galley is located forward in the main cabin to port, offering excellent functionality and storage for extended cruising. Sliding doors on both the port and starboard sides provide convenient access to the wide side decks, making provisioning, docking, and deck access easy and efficient. The galley features:
-Vitrifrigo AC/DC refrigerator with separate freezer
-Princess Ceran 3-burner electric cooktop
-Stainless steel toaster oven\air fryer\rotisserie
-Goldstar Ultra Oven convection\microwave oven
-U-Line ice maker
-Stainless steel double basin sink
-Corian style countertops
-Storage drawers and cabinets
-Teak & holly sole
***Mainship 430 Aft Cabin Dining***
Dining options include the elegant hardwood table at the U-shaped settee in the salon, as well as an additional table on the flybridge—perfect for alfresco meals with a view.
***Mainship 430 Aft Cabin Master Stateroom***
The full-beam master stateroom, located aft, offers a spacious and thoughtfully designed retreat. A walk-around queen-size berth is positioned to port, flanked by nightstands and reading lights for added comfort. The stateroom features a carpeted sole, a cedar-lined hanging locker, generous drawer and cabinet storage, as well as additional space beneath the berth.
Natural light fills the space through six curtained portlights, creating a bright and inviting atmosphere. For added convenience, stairs and a hatch provide direct access to the cockpit.
The private ensuite head includes a vanity, toilet, and a separate enclosed shower—delivering both comfort and privacy for extended stays aboard.
***Mainship 430 Aft Cabin Forward Guest Stateroom***
The forward guest stateroom, located in the bow, features a versatile V-berth with a filler cushion to create a comfortable double berth. Four portlights and an overhead hatch with a screen provide abundant natural light and ventilation. The space is thoughtfully appointed with a carpeted sole, built-in shelving, two cedar-lined hanging lockers, and ample drawer storage—offering both comfort and functionality for extended stays.
***Mainship 430 Aft Cabin Midship Guest Room***
The midship guest stateroom, located just forward of the galley, features side-by-side single berths with a shared nightstand and reading lights—perfect for accommodating guests or crew. Additional storage is available beneath the berths, complemented by a hanging locker and a small cabinet for personal belongings. A portlight and overhead hatch with a shade provide natural light and ventilation, while the carpeted sole adds a touch of comfort and warmth to the space.
***Mainship 430 Aft Cabin Guest Head***
The guest head is located to starboard, just forward of the lower helm and adjacent to the midship guest stateroom. It is well-appointed with a vanity, toilet, and a separate enclosed shower—providing both privacy and practicality for guests.
***Mainship 430 Aft Cabin Lower Helm***
The lower helm, located forward on the starboard side of the salon, is ideally positioned for short-term navigation tasks such as docking or locking. It also features a convenient side deck access door, allowing for quick and easy entry or exit. The lower helm features:
-Independent throttle and transmission controls
-Glendinning Synchronizer
-Windlass and trim tab controls
-VDO gauges
-Saturn compass
-ACR EPIRB (salon)
***Mainship 430 Aft Cabin Flybridge***
The flybridge is thoughtfully designed for both comfort and functionality. It features a canvas bimini with Isinglass panels, offering protection from the elements. To starboard, a large bench seat with storage provides ample seating, while an L-shaped bench seat to port and aft includes additional storage and a convenient table. At the center and forward, the captain's helm seat is flanked by two co-captain chairs, ensuring a comfortable and functional helm station. The flybridge helm features:
-Garmin GPSmap 943xsv multifunction display
-Garmin Echomap Ultra 106sv
-Garmin HD radar
-Garmin autopilot
-Uniden UM725G GPS VHF radio
-Independent throttle and transmission controls
-Glendinning Synchronizer
-VDO gauges
-Windlass and trim tab controls
-Richie compass
***Mainship 430 Aft Cabin Aft Deck***
The aft deck is securely enclosed by stainless steel rails and features a variety of practical amenities, including an outboard motor davit, an outboard motor storage mount, a large dock box for gear, fender storage, and space for the auxiliary anchor. Molded-in steps forward provide easy access to the flybridge, while port and starboard molded steps offer convenient access to the side decks.
***Mainship 430 Aft Cabin Cockpit***
The cockpit is well-equipped for both convenience and functionality, featuring a transom gate that leads to the swim platform. It includes a hatch for access to the master stateroom, as well as a lazarette access hatch for additional storage. A hot/cold freshwater shower is available for rinsing off after a swim, while aft power connections offer easy hookups. The non-skid deck ensures safety while moving around the space.
***Mainship 430 Aft Cabin Audio/Visual Equipment***
This yacht features the following audio and video equipment:
-ONN flat screen TV in the salon
-Pepwave WiFi
-Fusion MS-RA55 Stereo with speakers
***Mainship 430 Aft Cabin Engine/Mechanical Equipment***
This yacht features the following engine and mechanical equipment:
-Twin Caterpillar 3116 350 HP main engines with 4,073 hours
-ZF Hurth gearboxes
-Dripless shaft seals
-Racor fuel filters with vacuum gauges for each main engine
-X-Change-R oil change system
-Reverse cycle air conditioning/heating system (3 zones)
-Hydraulic steering system
-Trim tabs
-Seaward 20 Gallon water heater
-Wema water tank gauge
-Tankwatch4 holding tank level monitor system
***Mainship 430 Aft Cabin Electrical System***
This yacht features the following electrical equipment:
-Kohler 8EOZD 8 kW generator with 3,367 hours
-Charles 50 Amp battery charger
-2 - 8D main engine start\house batteries
-Generator start battery
-2 - 50 amp shore power cords
-Shore power connections fore and aft
***Mainship 430 Aft Cabin Tender and Equipment***
This yacht features the following tender and equipment:
-2019 AB Inflatables 10' aluminum RIB tender
-Yamaha 9.9 HP outboard
-Weaver tender davit system
***Mainship 430 Aft Cabin Deck Equipment***
This yacht features the following deck equipment:
-Lewmar anchor windlass with foot controls and remote control at each helm
-Delta plow anchor
-Chain anchor rode
-Kong swivel
-Bridle
-Danforth S2000 auxiliary anchor
-Stainless steel rails
-Stainless steel deck hardware
-Stainless steel fender holders
-Fender board
-Hinged mast
-Spreader lights
-Fresh water washdown forward
-Hot and cold freshwater shower aft
-Windshield covers
-Boarding gate each side
-Stainless steel boarding ladder
-Dock water connection aft
-Fiberglass swim platform
-Stainless steel swim ladder
-2 - two fender stainless steel storage racks
-Non-skid deck
***Mainship 430 Aft Cabin Safety and Fire Protection***
This yacht features the following safety and fire equipment:
-Sea-Fire R227 engine room fire suppression system
-Fireboy engine room fire suppression system discharge alarm on the flybridge
-Fire extinguishers
-Carbon monoxide detectors
-Dual horns
-Throwable life ring
-ACR EPIRB
***Mainship 430 Aft Cabin Exclusions***
-Personal effects
-Artwork
-General tools
***Additional Units Included***
-2019 AB Aluminum RIB 10 UL
***Disclaimer***
The Company offers the details of this vessel in good faith but cannot guarantee or warrant the accuracy of this information nor warrant the condition of the vessel. A buyer should instruct his agents, or his surveyors, to investigate such details as the buyer desires validated. This vessel is offered subject to prior sale, price change, or withdrawal without notice. - Condition
- Includes recent upgrades and maintenance