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Route deviation: +14% km, hidden fuel + AETR
When the driver deviates from plan, km can rise by +14%. Some deviation is forced (closed road, customer request); some is preventable (habit, old route, wrong nav).
Industry case: 100 trucks × 12,000 km/mo × €0.10/km × 14% = €16,800/mo of fuel + time loss.
Planned vs actual polyline
Lognari logs two polylines per trip:
- Planned: From OSRM/Mapbox/Google Maps API at trip assignment
- Actual: From telematics GPS points (1-minute resolution)
The delta:
| Trip | Planned km | Actual km | Δ | Traffic? | Preventable? |
|---|---|---|---|---|---|
| #5821 | 1,840 | 1,852 | +0.7% | — | No |
| #5823 | 2,140 | 2,298 | +7.4% | Fire | No |
| #5827 | 1,640 | 1,873 | +14.2% | None | 🚩 Yes |
| #5831 | 980 | 1,092 | +11.4% | Driver choice | 🚩 Yes |
Pattern analysis: same driver + same lane + recurring deviation → behaviour-change required.
Impact by fleet size
| Fleet | Monthly extra km | Annual impact |
|---|---|---|
| 100 trucks | 168,000 extra km | €200,000+ |
| 300 trucks | 504,000 extra km | €600,000+ |
| 1,000 trucks | 1.68M extra km | €2M+ + CO₂ report (560 t) |
Driver coaching loop
The Lognari pattern report lands at the ops centre monthly:
- Top 10 deviation-heavy drivers
- Which lanes
- Reason code (where given)
- Action recommendation
Pilot fleets see deviation drop from 14% → 6% after a 90-day coaching program.
What’s next
If your fleet doesn’t run automatic per-trip km comparison, 14% deviation is likely there — a pilot makes that concrete.
Reach out via the contact section — reply within one business day.
