Home Port; on the Delaware River at Fox Grove Marina Essington PA.

Kort Inspired Nozzle-Outboard in Well of Double Ender 2016-2017-2018

Kort diagram

Trawler with kort nozzle in Iceland

10" schedule 40 PVC Tee

Nozzle insert location. CL is location of stern tube.

Nozzle insert

Nozzle insert lower edge

Cut out for kort insert, keel void sealed, stern tube cut off

Nozzle intake spreader baffle first layer

Fiberglass tape secured with PVC adhesive for fiberglass mechanical attachment to hull.
(Fiberglass resin does not adhere to PVC)

Insert installed

Rough cut for cockpit/outboard access

Metal duct tape form, expanding foam spray from interior to create base for hull patch form.

Tape removed, excess foam cut away to inside face of hull.

First layer, chopped strand on foam base

Intake port
Intake starboard

Nozzle starboard

Nozzle port

Propeller aft skeg from 10" x 3/4" PVC trim board.

Cut out aft skeg PVC glued and clamped. 

Skeg leading edge eased

Fiberglass tape adhered with PVC glue for epoxy mechanical attachment.
PVC nozzle attachment points with no tape (notches) to be glued in-situ.

Propeller aft skeg installed.

1st fairing coat

Through hull removed, marine ply (scrap) backing plate epoxy in place.
Removal with hole saw overcutting through hull flange.

Cockpit scupper redirected to kort nozzle.

2nd layer epoxy with chopped strand.

Nozzle intake enlarged, edges to be eased with rasp.
Lazzaret interior

Nozzle forward intake edge beveled, to be ground smooth

Well head tray (pvc trim board) 

Well head with receiver blocks (Schedule 40 offcut and pvc trim board)

Well head dry assembly. Tray approx 3" above water line.

Well head fitted, well head tray dry fitted.

Well head tray box dry assembly.

Plywood sealed with penetrating epoxy

Penetrating Epoxy sealer from Progressive Epoxy

Well head tray box installed

Motor mount and well head tray box extension/retainer at fuel tank shelf.

Well head tray box lateral beam double 3/4" plywood, to secure to tray box aft to lazarette floor and transom beam. Box will be secured to cockpit well with motor mount (triple 3/4" plywood block), cockpit is factory secured to aft bulkhead at scupper.

Well head tray box lazarette lock edges and motor mount with penetrating epoxy, dry assemble.

Motor mount fitted

Well head box lazarette shelf and motor mount
Cockpit-Lazarette outboard "picture frame"
Cockpit-lazarette outboard picture frame dry fit.
Cockpit-lazarette outboard picture frame install.
Outboard test fit in lazarette/cockpit picture frame

Outboard mount cut to lower prop to center of nozzle.

Outboard remote relocated to cockpit

Lazarette hatch
Lazarette and outboard well painted
Outboard in lazarette

Outboard in lazarette picture frame with remote control cable

Nozzle and rudder

Propellor in nozzle

Fuel tanks installed

Outboard installed
Flotation foam for under lazarette

Template for under lazarette bulkhead filler
Aft bulkhead and under lazarette void
Aft bulkhead/under lazarette closed and fiberglass chopped strand sealed.
Flotation foam fill hole cut

Flotation foam equal parts resin and activator in cut of milk jugs, mix in cut off bleach bottle.

Flotation foam fill
Cockpit scupper extension set in chopped strand epoxy
Later this year I may change the current Tohatsu 6 hp for the 8 hp and not use the remote.
Current outboard, critical dimension for the well design is width at cowling 13.9 inches for 8 hp, 13.5 inches for 6 hp. Close enough for minor picture frame modification.

Fall haulout early November 2017.

The kort inspired modification produced much improved directional control with outboard and minimal impact on direction and speed under sail.
Prop in Kort inspired nozzle after one season November 2017

Kort inspired nozzle after one season November 2017

Propellor in nozzle November 2017

While a larger 2 cylinder 8HP outboard would provide more thrust and be quieter, the single cylinder 6HP outboard has been sufficient.

Winter 2017-18 projects:

Flow through Kort inspired duct:
Enlarge forward cutaways for improved reverse and forward water flow and provide smoother surfaces to reduce turbulence. 
Water intake for forward has a slightly larger gross area than output but projected on the same plane has significantly less cross sectional area. The rear output opening is in line with direction of water flow, the forward input opening is on the side of the kort inspired duct providing less cross section exposed to the direction of water flow and requiring water flow to make an approx 60 deg change of direction.

Enlarge forward cutaway
Weep at lower edge to be ground open and resealed
Forward nozzle entry enlarged, still more work to do on edges.
Nozzle forward edge eased

Flow at rear sleg:
Cutaway section and smooth nozzle rear skeg insert to reduce turbulence in forward.
Grind/fill and sand transition at top of nozzle rear skeg to hull for smoother water flow.

Rear skeg sweep cut
Well from nozzle

Forward edge eased, next grind edges (grey section) and build up.
Grind thin areas

Starboard cavities

Port cavity
Starboard, epoxy with chopped strand.

Penetrating epoxy coat

Outboard skeg and prop nozzle fore

Outboard prop nozzle aft

Outboard installed
Motor running in well

Electric Outboard:
Worth looking at as battery range is increasing.

Lazarette picture frame:
Grind/fill and sand cockpit/lazarette picture frame for improved appearance.

Complete vent lid at lazarette top.

Outboard control:

Modify throttle and shift controls for the outboard to reduce cockpit clutter.
Control Tee Knob for direct cable attachment at control cable bracket
Cockpit scupper:
Add scupper flapper valve to cockpit to outboard well scupper to reduce flow back into cockpit during reverse at 3/4 throttle..

Reinstall FISKSATRA logo.


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Ulladh pronounced "ul-la" (null lad).

Uladh the gaelic spelling for the territory of the U-Nail chieftains in the ancient Irish province of Ulster (English/Norse), originally the counties of Down and Antrim, but now including Derry, Armagh, Tyrone, Fermanagh, Donegal, Cavan and Monaghan, also referred to as Ulidia (Greek/Roman),.

Uladh was the home of a pre-celtic, cruithne (crew-en-ya) pictish tribe, who may have been descendants of prehistoric tribes indigenous to the British Isles since the retreat of the last ice age.

Archeological finds date first inhabitants to about 6,000 BC and trade goods from Rathlin Island, County Antrim off the northeast coast of Ireland made from porcellanite stone appearing in Egypt and Crete by 2,500 BC.

The early tribes of Ireland where displaced by later waves of migrants from mainland Europe; about 1700 BC by bronze age tribes, celtic tribes about 500 BC, and in the past two millenia; Roman trading posts, Viking settlements, English plantations... and in the 21st century a welcome increasing diversity from the European Union and the world.

SV Ulladh (for vhf clarity I use "sailing vessel ul-la") is named for the territory of the first peoples to settle in Ireland after the retreat of the last ice age.


Since 1949 Fisksatra Varv in the coastal town of Fisksatra Sweden, built fiberglass boats from dinghies to a 300 ton minesweeper for the Swedish Navy.

The Havsfidra 20's were built between 1968 and the late 1970's to Swedish Navy and Lloyd's certification standards.

The Havsfidra 20 and a larger version the Storfidra 26 where sold in the United States by Continental Yachts and Trawler Agency of Atlantic City NJ.

Havsfidra; sea-feather?
(fidra; to touch or tickle with a feather -Icelandic-English Dictionary, Clarendon Press 1874)