Trench warfare, considered a WWI phenomenon, has returned as the dominant form of line combat on the Ukrainian front between 2023 and 2026. The saturation of artillery, ISR and FPV has made covered subterranean positions the only positions that survive. This chapter describes characteristics, hazards and defensive considerations — not trench-assault procedures, which are outside the scope of the manual.
Why the trench returned
Three converging factors have brought the trench back to the centre of modern infantry tactics: continuous and widespread artillery, persistent drone surveillance, mass-produced cheap FPV. In this context any above-surface structure is detected and destroyed within hours. Protection requires vertical depth: every metre below ground drastically reduces the probability of engagement.
- Permanent drone surveillance: every external movement is observed
- Precision artillery (drone-corrected): average reaction time 5-15 minutes
- FPV with various warheads (anti-personnel, anti-vehicle, thermobaric): threat within 10-25 km of the line
- Cluster munitions and scatterable mines: contamination of the area around trenches
- Artillery on both sides: neither side has artillery 'surprise' anymore
Position typology
The modern 'trench' on the Ukrainian front is not a single structure: it is a system of coordinated positions with different protection levels. Terminology varies between units, but the functional structure is common.
| Type | Function | Characteristics |
|---|---|---|
| Fighting position (FP) | Individual or buddy firing position | Chest-deep, frontal parapet, alternate cover |
| Communication trench | Link between FP and rear | Zigzag or sinuous, partial cover, constant mud |
| Bunker / shelter | Shelter from artillery and drones | Subterranean, multiple accesses, overburden material |
| Command post (CP) | Section/platoon command | More protected, comms, map, observation system |
| Casualty Collection Point (CCP) | Casualty stabilisation | Near evacuation, heated if possible |
| Forward OP | Enemy observation | Concealed, isolated, comms to CP |
| Resupply cache | Forward ammunition and water | Distributed in covered points, never centralised |
Trench-specific hazards
The trench protects against some threats but generates others. Knowing the specific hazards is fundamental for those operating in static positions.
- FPV from above: enter directly into open parapets — overhead cover and nets are needed
- Grenades thrown from above: the vertical blind spot is the main trench danger
- Structural collapse: after heavy artillery, walls and overhead cover give way
- Trench foot and hypothermia: foot and legs in cold water cause chronic injury
- Extreme fatigue: long shifts with limited sleep erode judgement and reactivity
- Rats, parasites, contamination diseases (hep A, dysentery)
- Internal UXO: grenades, shells, sub-munitions in debris
- Toxic gases: in confined spaces fumes and combustion residue become dangerous
Non-combat losses to immersion foot are documented on the Ukrainian front in significant proportion, especially in autumn and spring. Waterproof footwear, frequent sock change (3+ per day), and foot drying at each rotation are fundamental prevention. A week of wet feet causes injury that removes the soldier from operations for weeks.
Overhead cover systems
Aerial trench cover is the single most documented defensive innovation on the Ukrainian front. Nets, rigid cover, and mixed systems reduce vulnerability to FPV and overhead grenades.
- Anti-drone netting: tight mesh blocks direct FPV trajectory but allows observation
- Rigid roofs (wood, sheet, soil overburden): protect against grenades but blind the position
- Mixed system: net over transit corridors, rigid roof over firing positions and bunkers
- Cover camouflage: no shine, no distinctive colours, integrated vegetation
- Maintenance: cover breaks under wind, snow, impact — continuous checking
Trench-life discipline
Living in a trench for days or weeks requires personal discipline different from movement combat. The trench is constantly observed; every habit becomes exploitable pattern of life.
- External movement only when necessary, never at predictable times
- Bodily waste in dedicated points, never random external — visible to thermal and drone
- Hot food only in thermal cover, avoid heating food in the open
- Sleep in rotation, never more than 50% of personnel sleeping simultaneously
- Kit always ready: helmet, plate carrier, IFAK, weapon within reach
- Phones and EM devices in faraday or away from the firing position
- No visible or IR light without cover (even small torches are visible to IR drones)
Rotations and support
Trench survival depends on rotation length and resupply capacity. On the Ukrainian front, rotations are often longer than planned due to difficulty of vehicular extraction. Units planning theoretical 24-48-hour rotations and ending up staying 5-10 days suffer losses to exhaustion and hypothermia.
- Plan for the worst case: food and water resupply for 5-7 days
- Water: 3-4 litres per person per day minimum, more in summer
- Munitions: stock for extended engagement without resupply
- Hot/cold: kit suited to season and trench microclimate
- Medical evacuation means: stretchers, sleds, pre-identified routes
- Comms with CP: PACE redundancy always, never one single comm path
Manual limits
Trench-assault procedures (trench raid, trench clearing) are out of scope for this manual. They are among the riskiest procedures in the entire infantry doctrine: they require intensive training, live rehearsals in mock-trench, and a chain of command integrated with supporting fires. Learning them from a reference manual is impossible and dangerous. This chapter only presents characteristics, hazards and defensive considerations.
Common mistakes
- Underestimating rotation length and required logistics
- Neglecting overhead cover out of laziness or lack of materials
- Living in wet boots for days and ignoring trench-foot symptoms
- Sleeping all together because 'the trench is quiet'
- Going outside at predictable times (dawn, lunch, dusk)
- Turning on torches or phone inside the trench, exposing IR signature
- Relying on a single evacuation route
- Not practising friendly fire prevention when a neighbouring unit changes
Lessons learned Ukraine
The Ukrainian trench of 2024-2026 is not the 1916 trench: it is a network of coordinated positions, overhead-covered, supported by on-call artillery, surveilled by both sides with persistent drone. Survival requires signature discipline, vertical depth, overhead cover and robust logistics. Documented losses to hypothermia, trench foot and exhaustion are comparable to losses from direct combat. The international volunteer entering a trench must drop every cinematic image: the trench is an environment of patience, maintenance and life discipline, not of heroic feats.