The Bow That Was Marked but Never Built

I don’t usually pay much attention to the bow shape of a vessel.
After years at sea, certain things fade into habit and you see them without noticing. But sometimes, when something is missing, your eyes catch it immediately.

It happened on one of my vessel.
While doing a normal round on the forecastle one afternoon, I leaned over the gunwale out of habit and looked down the stem. Normally, on ships of this size, you can clearly see the bulb just under the waterline. It’s always there as a distinct bulbous projection.

This time there was none. The forebody looked too fine, the line almost straight. There was no rounded projection or sign of a bulb beneath the surface.

Out of curiosity, I later checked the pilot card, and it was marked “Bulbous Bow – Yes.”
That didn’t match what I had seen. So, I decided to check the plans.

The Docking Plan and the Numbers

The docking plan gave a simple answer.
The projection ahead of the forward perpendicular was 0.115 metres ie. about 11 cms.

For a vessel almost 340 mtrs long, that’s practically nothing. To put it in perspective, the ship is nearly the length of three and a half football fields placed end to end, while that supposed “bulb” is about the thickness of a notebook or the width of your hand.

In technical terms, there was no bulbous bow at all but just a clean, fine stem designed to cut the water directly.

Still, because the pilot card said “yes,” I sent a short query to the yard. The reply came: “Yes, vessel has normal bulb.”
That’s when the question grew larger than just a checkmark in a column.

The Difference Between What’s Drawn and What’s Built

A bulbous bow isn’t an ornament. It’s a defined underwater structure, shaped to interfere with the bow wave in a way that reduces total resistance.
For that, it needs size, shape, and volume, typically projecting a metre or more forward and sitting below the waterline.

At 11 cms, there is no hydrodynamic contribution, no measurable wave interaction, and no design benefit.
The ship behaves like a straight-stem vessel.

So, if there is no bulb, why do the documents say there is one?

Over the years, bulbous bows have proved their value in reducing resistance, but with changing operational speeds and environmental rules, their effectiveness is being re-evaluated and in many cases, redesigned or removed.

Modern straight stem (left) Traditional bulbous bow (right)

Why Many New Vessels Are Built Without a Bulb

It’s not just this vessel. In recent years, many new tankers and large ships have been designed with either very small bulbs or none at all. The reason lies in how ships now operate and how design priorities have changed.

A bulbous bow is most effective only at a specific combination of speed, draft, and hull form. It works by reducing wave-making resistance, but only within a narrow speed range. When the ship moves slower or at a lighter draft, that same bulb can actually increase drag.

Since the introduction of the IMO’s EEXI and CII regulations, owners and operators have deliberately reduced speeds to save fuel and cut emissions. The industry calls it slow steaming, and it has changed everything about hull design. A large bulb that once helped at 16 knots becomes a penalty at 12 or 13.

To adapt, naval architects have started designing hulls with plumb or straight stems or very small faired-in bulbs tuned for lower speeds. These shapes give better performance over a wider range of conditions, especially when vessels spend long periods in ballast or in varying drafts.

Retrofits and newbuilds now follow the same logic, either resize the bulb for slow steaming or remove it altogether if operations vary too much. Class societies and research institutes have confirmed measurable fuel savings, sometimes up to 5–10% by simplifying the forebody.

So, while older designs carried prominent bulbs as a mark of efficiency, today’s ships are being optimised for a different era. The absence of a bulb is no longer a design omission, it’s often a deliberate choice for efficiency under modern operating realities.

A modern VLCC with a fine, straight stem, a design optimised for slow-steaming and variable draft operations.

How Errors Like This Happen

In shipbuilding, a lot of data moves forward automatically through templates and standard formats. A pilot card or stability form might have been copied from a sister vessel that had a bulb, or from a general specification where “Bulbous Bow – Yes” was already pre-filled. Once approved, that same entry passes through class, flag, and manuals without much rechecking. Unless someone notices, it quietly becomes fact by repetition.

To be fair, the yard may not be entirely wrong either. In shipyard terminology, “normal bow” often means not ice-strengthened, not axe-type, not special form. If that’s what they meant, they could be right from their point of view.

But by IMO pilot card standards, the field “Bulbous Bow – Yes/No” refers to an actual protruding underwater bulb, a measurable structure that affects hydrodynamics. A forward projection of only 0.115 mtrs doesn’t qualify. It’s too small to function as a bulb, and the correct entry should have been “No.”

So maybe everyone was right in their own context. The yard, by definition; and the ship’s record, by habit. But what went missing was the alignment between language and steel.

The pilot card that said “Yes” and the drawing that proved otherwise.

Why It Matters

For those at sea, the bow shape is not an academic detail, it quietly influences how a ship behaves.

Trim: A real bulbous bow adds underwater volume forward, giving slightly more buoyancy at the fore end. This can affect trim, especially when light or in ballast.
Maneuvering: Bow form changes how water flows along the hull. Ships with pronounced bulbs may handle a bit differently in shallow or confined waters.
Squat: In narrow channels, the flow around a bulb can alter how the vessel settles, while a fine straight stem behaves more predictably.
Docking: Docking plans depend on actual bow geometry. A bulb requires extra clearance and adjusted block positions below the forefoot.

If a vessel is recorded as having a bulb when it doesn’t, pilots and docking masters may expect handling or trim behaviour that isn’t there. Keeping the documentation aligned with the actual hull prevents that confusion.

What Research Shows

To check whether my understanding matched modern data, I referred to a study published in Maritime Technology and Society (Vol. 2, Issue 1, February 2023). The paper compared two common bow shapes, the faired-in bulb, which blends smoothly into the hull, and the ram-type bulb, which projects more distinctly forward. Using computational fluid dynamics (CFD) simulations, the researchers found that:

The faired-in bulb performs better at lower speeds (lower Froude numbers), reducing total resistance more effectively within its tuned range. The Froude number is simply a way of relating a ship’s speed to her length , in other words, how fast the vessel moves compared with the natural wave it creates.
The ram-type bulb performs better at higher speeds, offering a measurable power advantage when operated near its design point.

However, both designs are highly speed- and draft-dependent. When a ship operates off-design, for example, during slow steaming or in ballast a conventional bulb can lose its effectiveness and may even become a penalty, adding frictional resistance through its extra surface area and producing wave interference at the wrong point.

In contrast, a vessel with no bulb or a very small faired-in forebody avoids those off-design penalties. While it may forgo the small fuel savings that a tuned bulb can provide at one ideal speed, it delivers more consistent efficiency across today’s slower, variable operating profiles.

That observation aligns with what we see at sea. A straight-stem or plumb-bow vessel can run efficiently and predictably, even if it doesn’t gain the slight calm-water advantage that a well-tuned bulb offers at its design speed.

A Matter of Verification

This case was never about finding fault. It’s about how information quietly travels through the system, from design to approval to operation and how a single unchecked entry can stay unchallenged for years.

In shipping, small assumptions often turn into long-standing facts.
If a pilot believes the vessel carries a bulb, he may plan approach distances or turning rates differently.
If a drydock team prepares keel blocks expecting a bulb, the clearances may not match the actual forebody.
That’s why even a single line in the pilot card deserves to be correct.

In this case, the response confirming “Yes, normal bulb” came through the normal communication chain, and the instruction was to retain it as such. There was no disagreement recorded, and the matter was considered closed.

However, based on the as-built drawing and actual hull observation, it was clear that the projection was only 0.115 mtrs, effectively a faired-in type with no distinct bulb volume.

As a good practice, we now record it as “Bulbous Bow – Yes (faired-in type, 0.115 m projection).”
This keeps the documentation aligned with reality and satisfies the reporting format without contradicting official communication.

It’s a small adjustment, but it ensures the paperwork reflects the ship as she truly is,quietly setting the record straight.

The Lesson

This incident reminded me that we often take documentation at face value. But the ship itself remains the best record of truth.
It takes only a few minutes to cross-check the drawing with what we actually see at sea.
That simple habit can prevent years of wrong information being circulated.

It’s a bit like the old story of the “dead horse on the table” where a rule or practice continues long after its purpose has disappeared, simply because nobody remembers to ask why. In shipping too, forms get copied, data gets carried forward, and habits remain unquestioned until someone finally looks back at the source.

For a Master or Chief Officer, it’s worth remembering that what’s written in a file may have been copied from a previous ship, and what the yard calls “normal” may not match how we define it operationally.
So, when something doesn’t look right, even something as ordinary as a bow, it’s worth asking the question.

Sometimes, all it takes is one quiet look over the side to see what’s missing.

Perhaps the yard’s definition of “normal” is correct in its own context, but in practical seamanship it’s not what we would recognise as a bulbous bow.
It’s a quiet reminder that even in well-built ships and well-documented systems, small details can drift away from accuracy until someone looks a little closer and asks the simple question.

References

Ba Naga, M. H. (2023). Comparative Analysis of Faired-In Bulb and Bulbous Bow Ram Bow’s Shape on Total Ship Resistance. Maritime Technology and Society, 2 (1).
DNV (2022). Hull Form Optimisation for Slow-Steaming Operations.
MARIN (2020). Bulbous Bow Design in a Slow-Steaming World.
ABS (2020). Hydrodynamic Optimisation for Energy Efficiency.
Fujii H. & Takahashi T. (2018). Added Resistance in Waves of Modern Hull Forms. J. Marine Science & Technology, 23 (6).
Lloyd’s Register (2022). Ship Design for EEXI and CII Compliance.