Drone Inspection Services for Shipyards and Ship Construction

Geocartis carries out aerial survey, inspection and progress monitoring at shipyards and shipbuilding facilities in India. We cover yard construction and expansion works, block storage and movement, berth and dock occupancy, vessel build progress from erection through outfitting, external condition survey, and a dated record for milestone documentation. Capture is at 5 cm ground sample distance or better with survey control, or at close range where the deliverable is visual condition. We are based in Ahmedabad and work nationally.

We are a survey and geospatial services company. We do not build drones and we do not sell software.

Read this first: airspace at Indian shipyards

We are putting this before the sales content because it decides whether there is a job at all, and finding out afterwards is expensive for everybody.

Most shipyards in India of any scale fall into one or more of three categories that restrict or prohibit drone operation. They are defence establishments or defence public sector undertakings. They sit inside or adjacent to a port perimeter. Or they are close enough to an airfield to fall in a yellow zone with a reduced ceiling.

Under the Drone Rules 2021, red zone areas cannot be flown by a commercial operator at all. Yellow zones need permission from the relevant authority and carry a lower ceiling. Green zones allow operation to 120 metres above ground level without prior flight permission. A shipyard building naval vessels is a different proposition from a private yard building barges on a river, and the answer is site-specific.

So our first step on any shipyard enquiry is the airspace check, before a quotation exists. We map the site against the Digital Sky airspace map and tell you the position. On a meaningful number of yards the answer will be that the work cannot be done from the air, and we would rather say that in the first week than after a mobilisation.

Separately from airspace, the yard’s own security regime governs. Defence yards, yards with naval orders, and yards inside a port will have their own restrictions on photography that no DGCA clearance overrides. Where a yard has a naval order on the berth, the practical answer is often that aerial imagery of that berth is not permitted regardless of everything else.

We work within that. On mixed yards it is frequently possible to survey the infrastructure, the stockyard, the fabrication areas and the commercial berths while excluding a restricted berth entirely, with the exclusion agreed in writing before the flight and enforced by the flight plan rather than by editing afterwards.

Why this market is growing

Worth setting out, because it explains where the accessible work actually is.

India has committed a substantial programme to shipbuilding. A package of around ₹69,725 crore was approved in September 2025, structured around the Shipbuilding Financial Assistance Scheme with an outlay of ₹24,736 crore, a Maritime Development Fund with a corpus of ₹25,000 crore, and the Shipbuilding Development Scheme at ₹19,989 crore. Operational guidelines for the two shipbuilding schemes were notified in December 2025, and both run to 31 March 2036, with vessel assistance graded between 15 and 25 percent by category. A National Shipbuilding Mission has been set up as the inter-ministerial nodal body. Infrastructure status was notified in September 2025 for Indian-flagged vessels of 10,000 GT and above and India-built vessels of 1,500 GT and above.

The Shipbuilding Development Scheme targets annual output capacity of 4.5 million gross tonnage, through greenfield shipbuilding clusters of 1.0 to 1.2 million GT each and brownfield expansion of existing yards. In-principle approvals have been granted for three greenfield clusters, in Andhra Pradesh, Gujarat and Tamil Nadu.

Here is the practical point for a survey company, and it is not the obvious one. The largest accessible opportunity in this sector over the next several years is not flying inside a defence shipyard. It is surveying and monitoring the construction of the new yards themselves, and the brownfield expansion of existing ones.

A greenfield shipbuilding cluster is a very large civil construction project: land development, dredging and breakwaters, dry docks and slipways, quay walls, fabrication halls, gantry rails, stockyards, roads, services and utilities. That is earthwork, structures and progress monitoring, which is exactly what a survey company does, and during the construction phase the site is a construction site rather than a secured operational shipyard. The Gujarat cluster in particular sits in our home state.

What we actually do at a shipyard

Three tiers, in increasing order of restriction.

Yard construction and expansion

The most accessible work and the largest by value. Greenfield cluster development and brownfield expansion, surveyed as a construction project.

Pre-construction baseline and original ground level. Earthwork and dredging spoil quantities. Quay wall, dock and slipway construction progress. Fabrication hall and workshop structures. Gantry rail alignment and crane foundation works. Stockyard and laydown area formation and levels. Roads, drainage and services. As-built comparison against design on the civil works. Monthly progress capture with quantities and a dated record.

Our construction survey page covers the method in detail, and everything on it applies here.

Yard operations and logistics

Once a yard is operating, the aerial view answers questions the yard’s own systems answer poorly.

Block storage and laydown occupancy, with block positions and counts. Block movement between fabrication, assembly and erection areas across a series of captures. Berth, slipway and dry dock occupancy over time. Steel plate and section stockyard inventory and measurement. Yard congestion and material flow, which on a busy yard is a real productivity constraint that nobody has a picture of. Layout planning for reconfiguration or expansion.

This is the tier most yards underestimate. A monthly aerial series of a working yard produces a utilisation record that a planning department can use directly, and it costs a fraction of what a yard loses to a congested laydown area.

Vessel construction progress

The tier most affected by restriction, and where the honest scope is narrower than clients expect.

What we can record, subject to permission: block erection sequence and hull assembly progress from above and oblique, superstructure erection, deck-level outfitting visible from outside, scaffolding extent, external coating and painting extent by area, launch and float-out condition, and general external condition.

What this produces is a dated, georeferenced visual and measured record of the external build state at each capture. On a shipbuilding contract with milestone-linked payments, keel laying, launch, float-out and delivery, a dated independent record of physical state at each milestone has obvious value to both the yard and the owner, and to a financier funding against milestones.

For an owner’s representative or a project management consultant monitoring a build remotely, a monthly capture is a considerably better basis than a set of photographs taken from the quay.

What drone inspection is not

Shipbuilding is a heavily regulated technical industry with established inspection regimes, and a drone does not displace any of them. Being clear about this is not modesty, it is the difference between a credible provider and one that will be dismissed by any yard’s quality department in the first meeting.

Not classification survey. Survey during construction is carried out by the classification society, Indian Register of Shipping or another IACS member, and by statutory surveyors. Our output is not a class survey, not a substitute for one, and carries no class status.

Not non-destructive testing. Visual capture from a drone does not measure plate thickness, does not assess weld integrity, and does not replace ultrasonic, radiographic, magnetic particle or dye penetrant testing. A weld that looks acceptable in a photograph has not been tested.

Not coating verification. We can measure the area coated. Dry film thickness, surface preparation standard, adhesion and holiday detection all require instruments in contact with the surface.

Not dimensional control. Hull block dimensional accuracy is managed to millimetre tolerances using total stations, laser trackers and photogrammetric targets in a controlled process. Aerial photogrammetry at 5 cm GSD resolves to centimetres. It is two orders of magnitude away from block alignment tolerance and should never be presented as capable of it.

Not confined space inspection. Tanks, double bottoms, ballast spaces, cofferdams and voids are inspected with caged indoor drones designed for GNSS-denied collision-tolerant flight, which is a different aircraft, a different pilot skillset and a different service. We do not offer it, and we will tell you so rather than attempting it with an outdoor survey platform.

Not certification of anything. We record and measure. Sign-off belongs to the yard’s quality department, the class surveyor and the owner’s representative.

How we do it

Step 1: Permissions, in the right order

Airspace first, as set out above. Then the yard’s security clearance, which on a defence or port-located yard is the longer lead item and frequently requires crew details in advance. Then the agreed exclusion areas, written down. Then the yard’s safety induction and permit to work.

On a recurring monitoring programme, this setup happens once and the subsequent visits are straightforward. That is a good argument for buying it as a programme rather than as one-off visits, because the administrative cost of a single visit is disproportionate.

Our aircraft carry active Unique Identification Numbers and our pilots hold DGCA Remote Pilot Certificates, and we can supply crew and aircraft details for security clearance in advance.

Step 2: Data handling, agreed before the flight

Shipyard imagery is commercially sensitive at minimum and can be considerably more than that. We treat it accordingly.

Imagery goes to the commissioning party and nowhere else. We do not publish samples of shipyard work without written consent, and on defence-linked yards we do not publish at all. Where the yard requires it, raw imagery can be handed over in full and deleted from our systems at handover, with only the agreed derived outputs retained. Where a berth or area is excluded, the exclusion is enforced in the flight plan so the imagery is never captured, rather than captured and then cropped.

Rule 17 of the UAS Rules 2021 already prohibits sharing operational data with third parties without permission. On this sector we treat that as the floor and expect the yard’s own agreement to sit above it.

Step 3: Control, and the steel problem

A shipyard is the most hostile GNSS environment we work in, and the reason is that it is made almost entirely of steel.

Large steel structures, hull blocks, gantry and goliath cranes reflect satellite signals, so a receiver standing between two blocks can report a confident position that is well out through multipath. The same steel, plus welding current and heavy electrical plant, disturbs a drone’s magnetometer. A compass calibrated next to a block can be wrong, and the resulting heading error shows up as a flight that does not follow its planned lines.

We site control in open areas with clear sky view, away from structures, occupy for longer than we would elsewhere, and check the observation residuals rather than accepting the first fix. Compass calibration happens away from steel, and unexpected heading behaviour in flight is a reason to land rather than continue.

On a recurring programme, permanent control is established in positions that survive yard operations, which on a working yard means the perimeter, building corners and areas outside the laydown and traffic routes.

Step 4: Coordinate frames

Two different questions need two different answers, and conflating them causes confusion.

Yard-level work sits in UTM WGS84 or the yard’s own site grid, tied to their existing survey control where it exists. Civil construction, layout, stockyard, dock and quay work all belong here.

Vessel-level work is more useful in a frame relative to the vessel or the berth, because a hull under construction is not usefully described by its geographic coordinates and may in any case move. For block counting, occupancy and progress recording, position within the yard layout matters more than absolute coordinates.

We agree which frame each deliverable sits in at scoping, and where both are needed we deliver both with the relationship stated.

Step 5: Flight planning

Ground sample distance is pixel pitch multiplied by flying height divided by focal length. A 20 megapixel one-inch sensor with 5472 pixels across 13.2 millimetres has a pixel pitch of about 2.41 micrometres. With an 8.8 millimetre lens at the 120 metre ceiling that gives roughly 3.3 centimetres GSD, which suits yard-level survey.

Vessel and structure work needs closer flying and heavier oblique coverage. A ship under construction is a tall, vertical-sided object surrounded by scaffolding, and a nadir block reconstructs the deck and essentially nothing of the sides. Oblique passes at several headings and altitudes are the standard approach, and where external condition detail is the deliverable, flying is much closer and covers far less per sortie.

Gantry and goliath cranes are the dominant flight hazard. They span the building dock, move on rails, and carry lifting gear at height. Crane positions and operating envelopes are marked as exclusion volumes, crane operators are notified, and on an active dock the flying window is agreed with the yard rather than assumed.

Step 6: Capture on an operating yard

Hot work is everywhere. Welding, grinding and cutting produce smoke, flash and sparks, and an area with active hot work is both a poor imaging environment and one where an aircraft should not be. We plan around it and reschedule affected areas.

Wind at a coastal yard is more of a constraint than at inland sites, and it is often worse in the afternoon. Salt air is hard on equipment and the crew plans maintenance accordingly.

Overhead services, temporary power, welding cables run at height, and scaffolding all clutter the airspace close to a vessel. Close-range work near a hull is flown conservatively with a spotter, and we would rather abort a pass than take a marginal one.

People are present in numbers, at height, and often not looking up. Take-off, landing and transit routes avoid occupied areas entirely.

Step 7: Processing and reporting

Aerial triangulation, dense matching and classification for measured work. For the yard, that produces surfaces, quantities and layout layers in the normal way.

For vessel and block work the output is usually a combination of a reality mesh, oblique imagery organised by area and date, and counted or measured layers. Block counting and laydown occupancy are digitised against the yard layout rather than extracted automatically, because a stack of steel plate and a stored block look similar to an algorithm and quite different to a planner.

Reporting on a monitoring programme uses the same structure each epoch, referenced to the yard’s own area naming and, where relevant, to the vessel’s build strategy blocks. A report in our own terminology creates work for the yard’s planning team.

Accuracy and tolerance

Ground sample distance and accuracy are different quantities. GSD is the ground area one pixel covers. Accuracy is how close a coordinate is to the truth.

For a well-controlled photogrammetric block, horizontal RMSE typically lands between one and two times the GSD and vertical between two and three times. At 5 cm GSD that suggests roughly 5 to 10 centimetres horizontal and 10 to 15 centimetres vertical. Every deliverable carries the measured figures.

That is appropriate for yard civil works, earthwork quantities, dock and quay construction, stockyard measurement, layout and progress recording. It is appropriate for measuring the area of a coated surface or the extent of scaffolding.

It is not appropriate for anything to do with hull dimensional control, and we will not accept a scope that implies otherwise. Shipbuilding accuracy control operates in millimetres over block dimensions and erection tolerances. Aerial photogrammetry is not that instrument and no amount of flying lower closes a two-order-of-magnitude gap in a meaningful way.

The steel and multipath issues discussed above degrade results if not managed, which is why control siting on a shipyard takes longer than the flying.

Deliverables and output file formats

Raw imagery is handed over or deleted at handover, per the data handling terms agreed at the outset.

Ship recycling yards

A related and quite separate market, and one that matters particularly in Gujarat.

Alang in Bhavnagar district is the largest ship recycling location in the world, operating under the Recycling of Ships Act 2019 and the Gujarat Maritime Board, with the sector working towards Hong Kong Convention compliance.

Aerial survey supports this differently from shipbuilding. Plot boundary and occupancy across the yard, beached vessel position and dimensions, cutting progress on a vessel over time, material stockyard and secondary yard measurement, impervious floor extent, drainage and containment infrastructure, waste storage areas, and dated compliance documentation for the plot.

Airspace and permission apply as elsewhere and the coastal location introduces its own constraints. The compliance documentation angle is the one plot holders undervalue: a dated aerial record of plot condition and infrastructure is straightforward evidence for an audit that would otherwise rest on assertion.

Where we work

We are based in Ahmedabad and work nationally.

Gujarat. The Gujarat greenfield shipbuilding cluster area, Pipavav, Dahej, Hazira, Bharuch, Mundra, Kandla and the Alang ship recycling belt in Bhavnagar district. Being in Gujarat while a greenfield cluster is developed here is the most direct opportunity in this sector for us and, on the construction side, the least restricted.

Western India. Mumbai, Navi Mumbai and the Konkan coast, and Goa.

Southern India. Chennai and the Tamil Nadu cluster area, Kattupalli, Tuticorin, Kochi, Mangaluru and the Andhra Pradesh coast including Visakhapatnam and the Andhra cluster area.

Eastern India. Kolkata, Haldia and the Hooghly yards, plus Paradip and Dhamra.

On any of these, the airspace and security position is site-specific and we check it before quoting.

What we do not do

We do not carry out classification or statutory survey, and our output has no class status.

We do not carry out non-destructive testing of any kind.

We do not verify coating thickness, surface preparation or adhesion.

We do not perform dimensional control or accuracy control on hull blocks or erection.

We do not inspect confined spaces, tanks, double bottoms or internal compartments.

We do not certify quality, workmanship, compliance or completion.

We do not fly in red zones, over restricted berths, or against a yard’s security regime.

We do not retain or publish shipyard imagery outside the terms agreed with the yard.

Frequently asked questions

Can you fly at our shipyard? Possibly, and the honest answer requires a check. Many Indian yards are defence establishments, sit inside a port perimeter, or fall near an airfield, and some are in airspace where no commercial operator can fly. Send us the location and we will tell you the position before quoting.

We build naval vessels. Is this feasible at all? Sometimes, in part. On mixed yards it is often possible to survey infrastructure, stockyards, fabrication areas and commercial berths while excluding restricted areas entirely, with the exclusion built into the flight plan rather than applied by editing afterwards. Whether that is permitted is your security authority’s decision, not ours.

Does this replace class survey? No. Survey during construction is carried out by the classification society and statutory surveyors. Our output is a record and a measurement. It carries no class status.

Can you inspect welds? No. We can produce high-resolution imagery of an external surface. Weld integrity requires non-destructive testing, and a weld that looks acceptable in a photograph has not been tested.

Can you inspect inside tanks and ballast spaces? No. Confined space inspection uses caged collision-tolerant indoor drones designed for GNSS-denied flight. That is a different aircraft and a different service, and we do not offer it.

Can you check block dimensional accuracy? No. Block dimensional control runs to millimetre tolerances using total stations and laser trackers. Aerial photogrammetry resolves to centimetres and is the wrong instrument by two orders of magnitude.

What is the most useful thing you can do for a working yard? In our view, a monthly capture of yard utilisation: block storage and movement, laydown occupancy, berth and dock use, and stockyard inventory. Most yards have no objective picture of their own congestion, and it is a direct productivity cost.

We are building a new yard. Can you monitor the construction? Yes, and this is the strongest application. A greenfield shipbuilding cluster is a large civil project: dredging, breakwaters, docks, quay walls, fabrication halls, gantry rails and stockyards. Baseline survey, earthwork quantities, monthly progress and as-built comparison all apply, and during construction the site is a construction site rather than a secured operational yard.

How do you handle confidentiality? Imagery goes to the commissioning party only. Excluded areas are enforced in the flight plan so the imagery is never captured. Where required, raw data is handed over in full and deleted from our systems at handover. Nothing from a defence-linked yard is published.

What file formats do you deliver? Orthomosaic as GeoTIFF and JPEG. Surface models as GeoTIFF. Point cloud as LAS, LAZ and E57. Mesh as OBJ or FBX. Layout and asset layers as SHP, DXF and DWG. Occupancy and measurement tables as XLSX. Reports and milestone packs as PDF.

Get a quote

Send us the yard location and tell us what you need: civil construction monitoring, yard utilisation, vessel progress recording, or milestone documentation. Tell us whether the yard is defence-linked, inside a port perimeter, or has restricted berths.

We will check the airspace position and come back with what is feasible, what is not, the permissions you will need to arrange, and a price for the programme.

If the answer is that your yard cannot be flown, we will tell you in the first conversation.