Tool Gate · How it works
How the ECN Propagation Tripwire gate works
How the ECN Propagation Tripwire grades every open engineering change on five propagation points against a pinned date and rolls up to the worst: a past-effectivity gate forces BUILDING TO THE OLD PRINT when a mandated change is still open past its effectivity date.
How the gate works
This tool grades every open engineering change on five propagation points against a pinned evaluation date. It reads 7 ECNs and rolls them into one verdict — the worst, never the average — and then a gate that can only make it worse.
The 7 ECNs
| ECN | Verdict |
|---|---|
| ECN-1189 · released 2026-03-30 | PROPAGATED5 of 5 points landed · 93d |
| ECN-1195 · released 2026-06-05 | IN FLIGHT1 open point · 26d, inside the 30-day SLA |
| ECN-1201 · released 2026-05-02 | PROPAGATED5 of 5 points landed · 60d |
| ECN-1204 · released 2026-05-25 | PROPAGATED5 of 5 points landed · 37d |
| ECN-1207 · released 2026-06-15 | IN FLIGHT2 open points · 16d, inside the SLA |
| ECN-1210 · released 2026-06-24, mandatedfix first | IN FLIGHTmandated · 1 open point (floor stock) · PAST EFFECTIVITY 2026-06-28 — gate fires |
| ECN-1213 · released 2026-06-29, mandated | IN FLIGHTmandated · 1 open point · effectivity 2026-08-01, not yet due |
The verdict bands
A customer- or safety-mandated ECN that is still open on or after its effectivity date forces BUILDING TO THE OLD PRINT however young it is — the effectivity date is the day the old print became the wrong print. Worsen-only: it never lifts a verdict, and it releases the moment the open points close. The SLA runs from release; the gate runs from effectivity — two clocks.
In the worked sample it reads BUILDING TO THE OLD PRINT — Seven ECNs, none stranded — the SLA read alone would be CHANGES IN FLIGHT. But ECN-1210 is mandated, past its 2026-06-28 effectivity date, and still has an open point (floor stock), so the past-effectivity gate forces BUILDING TO THE OLD PRINT. ECN-1213 is also mandated with an open point, but its effectivity is a month out — mandated alone doesn't gate. Two clocks. The one thing to fix first: ECN-1210 — mandated, past effectivity, one open point (floor stock). Land that point first to release the gate; the verdict then falls to CHANGES IN FLIGHT..
Common questions
Can every ECN look survivable on the How the ECN Propagation Tripwire works and the company still read BUILDING TO THE OLD PRINT?
Yes. The roll-up takes the worst of 7 ECNs — never the average — then a worsen-only gate, the Past-effectivity gate, escalates when trouble clusters. In the worked sample it reads BUILDING TO THE OLD PRINT because seven ECNs, none stranded — the SLA read alone would be CHANGES IN FLIGHT. But ECN-1210 is mandated, past its 2026-06-28 effectivity date, and still has an open point (floor stock), so the past-effectivity gate forces BUILDING TO THE OLD PRINT. ECN-1213 is also mandated with an open point, but its effectivity is a month out — mandated alone doesn't gate. Two clocks.
What is a worsen-only gate?
A dispositive rule that can only lower a verdict, never raise it. One fatal flaw overrides an otherwise-set of survivable lines, because a single disqualifying gap shouldn't hide behind an average of the healthy ones. The tool also names the one thing to fix first — here, "ECN-1210 — mandated, past effectivity, one open point (floor stock). Land that point first to release the gate; the verdict then falls to CHANGES IN FLIGHT.".
Grades engineering-change propagation from a log you enter — it scores changes, never people, and modifies nothing in your PLM or ERP. Not a compliance determination, not certification of any standard, and not legal advice.
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<iframe src="https://redhub.ai/visuals/tool/ecn-propagation-tripwire.html" title="How the ECN Propagation Tripwire gate works — RedHub AI" width="760" height="2050" loading="lazy" style="border:0;width:100%;max-width:760px"></iframe>
<p style="font:14px/1.5 system-ui,sans-serif"><a href="https://redhub.ai/visuals/tool/ecn-propagation-tripwire">How the ECN Propagation Tripwire gate works</a> — by <a href="https://redhub.ai">RedHub AI</a>, the AI that tells you when to doubt it.</p>Image + link — a static picture for any blog
<a href="https://redhub.ai/visuals/tool/ecn-propagation-tripwire"><img src="https://redhub.ai/visuals/tool/ecn-propagation-tripwire-share.png" alt="Diagram of the ECN Propagation Tripwire: open engineering changes rolled up worst-not-average, a past-effectivity gate, and the shop reading BUILDING TO THE OLD PRINT on one overdue mandated ECN." width="760" loading="lazy" style="max-width:100%;height:auto;border-radius:16px"></a>
<p style="font:14px/1.5 system-ui,sans-serif"><a href="https://redhub.ai">RedHub AI</a> — the AI that tells you when to doubt it.</p>
This is how ECN Propagation Tripwire works. More diagrams in the Visual Field Guide.