The mysterious case of the inverted bow

Trudging down the canal path on my seemingly daily pilgrimage to Screwfix, my attention was grabbed by an imposing steel form projecting from the water. I was looking at what appeared to be the ‘inverted’ bow profile of an impressive, period-esque, working-style narrowboat, branded “GJCCo Pilot”. Rather than your conventional bulbous bow that hangs cheerfully over the water, this one spiked strangely downwards, loosely resembling the profile of a cowcatcher (interestingly also called a ‘pilot’) on an old steam locomotive.

The unusual and impressive inverted bow on this replica Blisworth Pilot ‘tunnel tug’

I was lucky enough to bump into the owner, who informed me that she is a "modern" (1970s) replica of the much older (1908) wood-made, stream-powered Blisworth "Tunnel Tug" Pilot. Along with its sister boat, the "Spider", the Pilot formed part of a small fleet tasked with pulling engineless (e.g. horse-drawn) canal boats through the cavernous 2.8km Blisworth Tunnel on what's now known as the Grand Union canal. As a side note, before the advent of steam-powered tugs, narrowboaters would have to lie perpendicular to their boat and use their legs to push along the inside of the tunnel walls in a practice known as "legging".

Boaters propelling their boat through the Blisworth tunnel using just their legs

But back to that inverted bow. Also known as an ‘x-bow’, the design - whist almost futuristic in appearance - is far from a recent innovation. The inverted bow was often seen on late 19th and early 20th century battleships, like the pre-dreadnought battleship USS New Hampshire (see below), although likely dates back to Viking times. After falling out of fashion, inverted bows began to make a comeback due to their perceived superior hydrodynamic performance (length-to-beam ratio and reduced buoyancy etc.) and enhanced handling (e.g., lateral stability). These designs are typically found on high performance naval vessels and super yachts.

Inverted bows seen on battleships (old & new) and high-performance yachts

So, why did the designer of the Blisworth Pilot ‘tunnel tug’ opt for this unusual design? The owner speculated that it might be to help clear any debris from the boat’s path to protect the propeller. The design also reminded me of some of the ice-breaker narrowboats on the cut, and I wondered whether the inverted design had additional structural strength element factored in, given the tough and cold working conditions of the tunnel tugs. The design would almost certainly also help the boat navigate a straight line, experiencing less drift than one with a regular bow shape - certainly something that could be useful in a long narrow tunnel setting. Any other ideas??

Regardless of the reason, I thought that this unusual design deserved a call out - both for it’s historical interest, and simply its badass looks!!