In aviation, every minute on the ground matters On-chain operational checklist + KPI measurement + NFT reputation badges Blockchain-based Aircraft Turnaround System | BCN | 2026
Winner — Blockchain-based Turnaround Checklist Challenge Decode Travel Barcelona 2025 Issued jointly by Chain4Travel, Camino Network, and Vueling Airlines (December 2025)
| Role | Contributor | Contribution |
|---|---|---|
| Smart Contracts | Alejandro Sáez | On-chain turnaround logic, KPI/SLA computation, cryptographic certification, NFT badge system |
| Frontend & dApp | Daniel Montaño | Frontend, wallet integrations, full decentralized application |
| Operations Design | Cátia Ribeiro | Real-world aircraft turnaround expertise, task model, actor responsibilities, SLA logic |
The TurnaroundChecklist system introduces a next-generation digital operating model for aircraft turnarounds, transforming the entire arrival-to-departure process into a cryptographically certified, on-chain operational checklist.
Each turnaround is represented by a dedicated smart contract that:
- Enforces task accountability
- Measures real-time performance
- Computes SLA/KPI outcomes
- Produces an immutable operational certificate
A complementary TurnaroundBadge NFT contract enables a reputation-based incentive layer for operational actors delivering flawless performance.
Aircraft Arrival → 27 Tasks On-Chain → Real-Time KPIs → Certified Turnaround + NFT Badge
- Bring operational transparency and accountability to aircraft turnarounds
- Provide objective, tamper-proof SLA and KPI measurement
- Eliminate post-operation disputes through cryptographic evidence
- Introduce performance-driven incentives for ground operations
- Serve as a foundational layer for automation, analytics, and compliance
The solution consists of four core components:
Manages a single aircraft turnaround end-to-end:
- Task lifecycle management
- Role-based execution
- KPI/SLA computation
- Final certification
- Event-driven audit trail
- Optional badge issuance
Initializes a standardized 27-task turnaround checklist with:
- Predefined operational actors
- Deadlines relative to scheduled arrival
- Default mandatory flags
Defines common enums, structs, and events used across contracts.
Issues performance badges linked to a specific turnaround and actor:
- Fully on-chain metadata
- IPFS-hosted imagery
- Strong traceability to operational outcomes
The system models six standard turnaround actors, each operating through a dedicated blockchain wallet:
| Actor | Responsibility |
|---|---|
| Ground Handling | Aircraft marshalling, push-back, GPU connection |
| Cleaning | Cabin cleaning and waste removal |
| Fuel | Fuelling and fuel upload confirmation |
| Catering | Catering loading and galley provisioning |
| Flight Crew | Pre-flight checks, departure readiness |
| Gate | Boarding, door management, PAX flow |
Each wallet enables:
- Clear responsibility attribution
- Verifiable action ownership
- Actor-level performance analytics
Each turnaround contains 27 predefined operational tasks, each defined by:
| Field | Description |
|---|---|
actor |
Responsible operational actor |
deadline |
Time-bound deadline (relative to scheduled arrival) |
mandatory |
Whether task is mandatory or optional |
status |
Pending / OnTime / Late |
justification |
Optional delay justification (human-readable) |
Late tasks that are formally justified do not count against SLA or KPI metrics, reflecting real-world operational exceptions.
The contract uses OpenZeppelin AccessControl, aligned with real aviation governance:
| Role | Permissions |
|---|---|
DEFAULT_ADMIN_ROLE |
Role administration, actor wallet management, badge contract configuration |
OPS_ROLE |
Turnaround certification, mandatory task overrides, operational override |
| Actor Wallets | Complete assigned tasks, justify delays for owned tasks |
Each smart contract represents one specific turnaround, initialized with:
- Off-chain turnaround ID
- Airport code
- Scheduled arrival and departure times
- Automatic 27-task generation
- Actors mark tasks as completed via their wallets
- System evaluates timeliness in real time
- KPIs update continuously on-chain
- Late tasks may be justified with human-readable reasons
- SLA impact is dynamically recalculated
Once all mandatory tasks are completed, OPS certifies the turnaround:
- On-time vs late task count
- SLA breach status
- Actual operational duration
- A cryptographic certificate hash is generated and stored immutably on-chain
The contract computes and exposes:
| Metric | Description |
|---|---|
| Total tasks | Count of all turnaround tasks |
| Tasks on time | Tasks completed within deadline |
| Unjustified late tasks | Late tasks without formal justification |
| SLA breach indicator | Boolean: whether SLA was breached |
| Actual duration | Real operational time (arrival to departure) |
These KPIs are trustless, auditable, and machine-readable, enabling seamless integration with analytics platforms (Power BI, Tableau, etc.).
The TurnaroundBadge ERC-721 contract introduces a reputation mechanism:
- One badge per (turnaround, actor) pair
- Minted only if the actor:
- Participated in the turnaround
- Had zero unjustified late tasks
- Metadata is fully on-chain
- Visual assets stored on IPFS
These badges are non-financial reputation markers, not speculative assets.
A comprehensive event log ensures full transparency:
| Event | Trigger |
|---|---|
TurnaroundCreated |
Contract deployment |
TaskCompleted |
Actor marks task done |
MandatoryTaskChanged |
Admin modifies mandatory flag |
DelayJustified |
Actor submits delay reason |
TurnaroundCertified |
OPS certifies completion |
BadgeMinted |
NFT badge issued to actor |
Supports: post-operation audits, dispute resolution, regulatory compliance, historical performance analysis.
- Administrative and OPS roles must be tightly secured (hardware wallets recommended)
- Actor wallets represent real operational authority
- Badge minting restrictions fully enforced in production
block.timestampusage appropriate for minute-level operational windows- One-contract-per-turnaround model minimizes systemic risk and simplifies audits
This architecture transforms the aircraft turnaround from a reactive, opaque process into a programmable, certifiable operational system.
- Verifiable turnaround execution
- Objective SLA enforcement
- Performance-driven accountability
- AI-driven disruption management
- Automated settlements and penalties
- B2B operational reputation systems
- Data-driven continuous improvement
It introduces a trust layer for aviation ground operations, ready for scalable, digital-first ecosystems.
| Layer | Technology |
|---|---|
| Smart Contracts | Solidity + OpenZeppelin |
| Blockchain | Camino Network (Chain4Travel) |
| NFT Standard | ERC-721 |
| Access Control | OpenZeppelin AccessControl |
| Asset Storage | IPFS |
| Frontend | dApp (wallet integration) |
| Analytics Integration | REST API / Power BI |
TurnaroundChecklist/
├── README.md # This document
├── contracts/
│ ├── TurnaroundChecklist.sol # Core turnaround contract
│ ├── TurnaroundBadge.sol # ERC-721 NFT badge contract
│ ├── TurnaroundTemplates.sol # 27-task template library
│ └── TurnaroundTypes.sol # Shared enums, structs, events
├── docs/
│ ├── architecture.md # Technical architecture detail
│ ├── task-model.md # 27-task breakdown & SLA logic
│ └── actor-model.md # Operational actor definitions
├── data-layer/
│ ├── kpi_schema.sql # KPI data schema for analytics
│ └── kpi_dashboard.py # Python ETL for Power BI
└── assets/
└── badge-metadata/ # NFT badge metadata templates
- In aviation, every minute on the ground matters — Medium, Cátia Ribeiro
Cátia Ribeiro — Operations Design & Strategy Product & CX strategist exploring the future of aviation and travel tech. Designing systems where technology meets human experience. Barcelona, 2026
"In aviation, every minute on the ground matters. This system makes every second accountable."