Visual Reverse Engineering for Legacy Aviation Maintenance Logs

The most dangerous code in your enterprise isn’t the feature you shipped this morning—it’s the aviation maintenance log system written in 1998 that no one understands, yet every flight safety audit depends on. In the aviation industry, "legacy" isn't just a technical term; it’s a liability. When your maintenance, repair, and overhaul (MRO) workflows are trapped inside a 25-year-old Delphi or PowerBuilder application, the risk of a "Big Bang" rewrite often outweighs the pain of staying put.

But staying put is costing you millions. With a global technical debt mountain reaching $3.6 trillion, aviation and aerospace firms are finding that manual reverse engineering is no longer a viable path forward.

TL;DR: Visual Reverse Engineering allows enterprises to bypass years of manual documentation by recording legacy workflows and automatically generating modern React components and API contracts, reducing modernization timelines by 70%.

The Archaeology Trap: Why Legacy Aviation Rewrites Fail#

70% of legacy rewrites fail or significantly exceed their timelines. In aviation, the failure rate is often higher due to the sheer complexity of regulatory compliance and the "Black Box" nature of the systems. Most of these systems suffer from a chronic lack of documentation—67% of legacy systems have no functional specs remaining.

When an architect is tasked with modernizing a maintenance log system, they usually start with "Software Archaeology." They spend months interviewing retired developers, sniffing network traffic, and trying to map out how a "simple" part replacement workflow triggers eighteen different database updates across three disparate systems.

This manual process takes an average of 40 hours per screen just to document and prototype. For a standard MRO suite with 200+ screens, you are looking at years of work before a single line of production-ready modern code is written.

The Cost of Tradition vs. Visual Reverse Engineering#

What is Visual Reverse Engineering?#

Visual Reverse Engineering flips the script on modernization. Instead of starting with the source code (which might be lost, obfuscated, or written in a dead language), we start with the behavior.

By using Replay, engineers record real users performing actual maintenance tasks—like logging a bird strike inspection or clearing a "Deferred Maintenance Item" (DMI). Replay captures the DOM mutations, the network calls, and the state transitions. It then uses AI to translate those observations into documented React components and TypeScript interfaces.

This isn't just a screen recording; it’s a functional extraction.

From Pixels to Production-Ready React#

When you record a session in Replay, the platform identifies patterns in the legacy UI. It recognizes that a specific grid in an old Windows-based terminal is actually a data table with sorting, filtering, and CRUD operations.

Here is an example of the type of clean, modular code Replay generates from a legacy maintenance log extraction:

typescript
// Generated via Replay Visual Extraction
// Source: Legacy MRO System - Component: PartInspectionForm
import React, { useState, useEffect } from 'react';
import { Button, TextField, Alert } from '@/components/ui';
import { useAviationLogic } from '@/hooks/useAviationLogic';

interface InspectionData {
  tailNumber: string;
  partId: string;
  inspectionDate: string;
  technicianId: string;
  status: 'PASS' | 'FAIL' | 'DEFERRED';
}

export const PartInspectionForm = ({ initialData }: { initialData?: InspectionData }) => {
  const [formData, setFormData] = useState<InspectionData>(initialData || {
    tailNumber: '',
    partId: '',
    inspectionDate: new Date().toISOString(),
    technicianId: '',
    status: 'PASS'
  });

  // Replay extracted this business logic from legacy network interceptors
  const validateTSO = (hours: number) => {
    return hours < 10000; // Time Since Overhaul threshold preserved
  };

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    // API Contract generated by Replay AI Automation Suite
    const response = await fetch('/api/v1/aviation/logs', {
      method: 'POST',
      body: JSON.stringify(formData),
    });
    if (response.ok) {
      console.log("Maintenance log synchronized successfully.");
    }
  };

  return (
    <form onSubmit={handleSubmit} className="space-y-4 p-6 bg-white rounded-lg shadow">
      <h2 className="text-xl font-bold">Log Maintenance Action</h2>
      <TextField 
        label="Tail Number" 
        value={formData.tailNumber} 
        onChange={(e) => setFormData({...formData, tailNumber: e.target.value})} 
      />
      {/* Additional fields extracted from legacy UI structure */}
      <Button type="submit">Submit Inspection</Button>
    </form>
  );
};

💰 ROI Insight: Manual modernization costs approximately $25k-$50k per screen when factoring in developer hours and BA requirements. Replay reduces this to under $5k per screen by automating the discovery and boilerplate phases.

The 3-Step Workflow for Aviation Log Modernization#

Modernizing a mission-critical aviation system requires more than just new code; it requires a guarantee of parity. You cannot afford for a "Time Since Overhaul" (TSO) calculation to be off by even a decimal point.

Step 1: Recording the Source of Truth#

Instead of reading 500 pages of outdated documentation, a subject matter expert (SME) performs the maintenance log entry while Replay records the session. This captures the "happy path" and the edge cases that are often hidden in the legacy code's conditional logic.

Step 2: Extraction and Architecture Mapping#

Replay’s AI Automation Suite analyzes the recording. It maps the legacy UI elements to your modern Design System (Library). If the legacy system used a specific COM+ object to validate a part number, Replay identifies the network request or the client-side logic and generates a corresponding API contract.

Step 3: Technical Debt Audit and Refactoring#

Once the "Blueprint" is generated, the Enterprise Architect reviews the Technical Debt Audit. Replay highlights where the legacy logic is redundant or where security vulnerabilities (like hardcoded credentials or lack of encryption) existed in the old system.

typescript
// Example: Replay-generated API Contract (OpenAPI/Swagger)
// Extracted from legacy traffic analysis
paths:
  /api/v1/aviation/logs:
    post:
      summary: "Create maintenance log entry"
      parameters:
        - name: "X-Technician-Signature"
          in: "header"
          required: true
          schema:
            type: "string"
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/MaintenanceLog'

⚠️ Warning: Never trust legacy API logic blindly. Always use Replay’s E2E test generation to verify that the new system's outputs match the legacy system's outputs bit-for-bit before decommissioning.

Solving the "Black Box" Problem in Regulated Environments#

For industries like aviation, healthcare, and government, "the cloud" isn't always an option. Many maintenance logs live on air-gapped networks or in highly regulated data centers.

Replay is built for these environments. It offers an On-Premise deployment model that ensures your sensitive maintenance data never leaves your infrastructure. Because it is SOC2 and HIPAA-ready, it meets the rigorous compliance standards required for FAA Part 145 repair stations and aerospace manufacturing.

Preserving Business Logic without the Source Code#

The biggest fear in reverse engineering is missing a hidden business rule. For example, an aviation log might have a rule that says: "If the ambient temperature was below freezing during the inspection, the hydraulic fluid check must be repeated."

If this logic is buried in a compiled binary, a manual rewrite will likely miss it. Replay captures the state change when the user interacts with the temperature field, ensuring that the logic is surfaced and documented in the modern Blueprint.

• •Library: Automatically syncs extracted components to your corporate Figma or React Design System.
• •Flows: Visualizes the entire user journey through the legacy system, identifying bottlenecks.
• •Blueprints: An interactive editor where architects can refine the generated code before it hits the repo.

The Future of Modernization is Understanding#

The 18-month average enterprise rewrite timeline is a relic of the past. By shifting the focus from "writing code" to "understanding behavior," organizations can move from black boxes to documented, modern codebases in days or weeks.

Visual reverse engineering isn't just about speed; it's about accuracy. It provides a video-based source of truth that bridges the gap between the grizzled technician who knows the legacy system's quirks and the modern developer who knows React and Node.js.

💡 Pro Tip: Use Replay to generate your E2E test suite simultaneously with your code. This ensures that your "Definition of Done" includes 100% parity with the legacy system's behavior.

Frequently Asked Questions#

How long does legacy extraction take with Replay?#

While manual documentation and prototyping take an average of 40 hours per screen, Replay reduces this to approximately 4 hours. Most enterprise teams see a 70% average time savings across the entire project lifecycle, moving from 18-month timelines to just a few months or even weeks for specific modules.

What about business logic preservation?#

Replay captures every user interaction and the resulting system response. By analyzing network payloads and UI state changes, the AI Automation Suite can reconstruct the underlying business logic, even if the original source code is unavailable or unreadable. This ensures that critical rules—like aviation safety thresholds—are preserved in the new system.

Does Replay require access to our source code?#

No. Replay uses Visual Reverse Engineering, which works by recording the application as it runs. This is particularly useful for legacy systems where the source code is lost, or for third-party software where you only have access to the user interface.

Is Replay secure for aviation and defense data?#

Yes. Replay is built for regulated environments and is available for On-Premise deployment. It is SOC2 compliant and designed to handle sensitive data in accordance with industry-specific regulations like HIPAA or FAA requirements.

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