Aerospace Defense Contractor Tracks Inspection Response Across 20 Production Lines

91 call buttons deployed across 20 lines. In-process inspection calls tracked from request to completion for the first time.

At a Glance

Detail	Value
Industry	Aerospace — Defense Systems Manufacturing
Facility	20 production lines, multiple inspection stages per line
Key Result	In-process inspection tracking from call to completion across every build phase
Scale	91 five-key call buttons, 10 watch pagers, button board displayed on floor TVs
System	5-key call buttons, watch pagers, wireless light, signal repeaters, SMS/email escalation, advanced software

The Challenge

This aerospace and defense manufacturer operates 20 production lines building complex assemblies that require multiple in-process inspections at different build phases. Each line doesn't just need one inspection — it needs several, at specific stages, from specific qualified inspectors. The volume of inspection requests across 20 lines created a coordination challenge that manual methods couldn't handle.

The core problem was visibility. When an operator at Line 12, Stage 3 called for an inspection, nobody knew:

Whether the request had been received. Inspectors moved between lines and stages throughout the shift. A call from one station could easily be missed while an inspector was occupied at another.
How long the operator waited. There was no timestamp on when the inspection was requested versus when the inspector arrived. Wait time was invisible.
Which stages were bottlenecks. With multiple inspection points per line across 20 lines, the total number of daily inspection calls was substantial — but without data, the plant couldn't identify which stages or lines generated the most wait time.

For an aerospace defense environment, inspection isn't optional — it's a gated quality requirement at each build phase. A missed or delayed inspection doesn't just slow production; it can halt an entire line until the required sign-off is obtained. The cost of an uninspected unit sitting idle while an inspector is occupied elsewhere was real but unmeasured.

The facility's continuous improvement leader — responsible for driving lean initiatives across multiple sites — recognized that the inspection response gap was a significant source of hidden waste.

Why They Chose an Andon System

The CI leader evaluated solutions that could address three specific needs:

Call-level granularity. Each of the 20 lines needed multiple call buttons — one per inspection stage — so the system could distinguish between a Stage 1 inspection call and a Stage 4 inspection call on the same line. Generic "help needed" alerts wouldn't provide enough information.
Real-time visual management. The team wanted active calls displayed on TV monitors mounted on the production floor, giving supervisors and inspectors a live view of where calls were open and how long they'd been waiting. The button board served as a digital visual management tool — a core lean manufacturing principle.
Off-floor escalation. When inspectors or supervisors were away from the production area, SMS and email notifications ensured critical calls still reached the right people. This was especially important for escalation — if an inspection call went unanswered past a threshold, the system needed to notify the next person in the chain automatically.

The five-key call button format was selected to support multiple call types per station — different keys mapped to different inspection stages or support categories, allowing operators to specify exactly what they needed with a single button press.

The Implementation

Scale of Deployment

The deployment was one of the largest single-site Andon installations:

91 five-key call buttons distributed across 20 production lines, covering every inspection stage and support call point
10 watch pagers for inspectors and key support personnel
4 signal repeaters to ensure radio coverage across the full production floor
1 CA transmitter connecting all hardware to the software system
1 wireless stack light for high-priority visual alerts
Advanced software license with full reporting, escalation sequences, and button board display
SMS/email subscription for off-floor notifications and escalation alerts

Button Board Configuration

A key focus during implementation was the button board display. With 91 call points generating activity throughout the shift, the team needed a way to filter and organize the information displayed on floor TVs. Configuration focused on:

Active-call filtering to show only open calls, preventing the board from being cluttered with resolved entries
Layout optimization for horizontal TV displays, ensuring line and stage identifiers were readable from a distance on the production floor
Multi-TV consideration to display different production areas on different screens, allowing supervisors to focus on their zones

Escalation and Notification

The SMS/email subscription was a critical component. Inspection calls that went unanswered past a configured timeout triggered automatic notifications to backup inspectors and supervisors — even if they were off the production floor, in meetings, or at another facility area. This closed the loop that manual paging systems left open.

The Results

Inspection Response Tracked End-to-End

For the first time, the facility had data on every inspection interaction: when the call was placed, which line and stage it originated from, when the inspector arrived, and when the inspection was completed. This end-to-end tracking transformed inspection coordination from a manual, unmonitored process into a measured workflow.

Visual Management on the Floor

The button board displayed on production floor TVs became a real-time operations dashboard. Supervisors could see at a glance which lines had open inspection calls, how long those calls had been waiting, and whether the right personnel had been dispatched. This visual management layer — a cornerstone of lean manufacturing — replaced the previous state of having no visibility into inspection queue status.

Data for Continuous Improvement

The CI leader now had the data needed to drive improvement initiatives across the facility. Pareto reports identified which lines and which inspection stages generated the most calls and the longest wait times. This data supported targeted kaizen events focused on the highest-impact bottlenecks rather than relying on anecdotal evidence about where delays occurred.

Sustained Commitment

The facility renewed its SMS/email subscription annually — a clear indicator that the notification and escalation features delivered ongoing value. For a facility processing hundreds of inspection calls weekly across 20 lines, the ability to escalate unanswered calls off-floor was not a feature to trial and drop; it was operational infrastructure.

What They Said

The continuous improvement leader approached this deployment with a multi-site perspective. The inspection tracking challenge at this facility wasn't unique — it was a pattern he'd seen across manufacturing operations where in-process quality gates created coordination bottlenecks. The Andon system gave him a standardized framework for measuring and improving that coordination.

The scale of the deployment — 91 call buttons across 20 lines — reflected the reality of aerospace manufacturing: quality inspection isn't a single event on each line, it's a series of gated checkpoints that each require timely response. Every missed or delayed inspection ripples through the production schedule.

What made this implementation distinctive was the focus on inspection tracking rather than the more common maintenance-call use case. The system proved equally effective for quality-gated workflows where the "responder" is an inspector rather than a maintenance technician — and where the cost of waiting is measured in halted production lines, not just individual machine downtime.

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