A quality escape is a nonconforming part that makes it past every check and lands on your dock, or worse, on your line. When one shows up, the first instinct is to blame the machine or the operator. Most of the time the problem started well before that, at a handoff where a requirement got lost, misread, or never passed along.
For buyers running aerospace, defense, or medical programs, knowing where those handoffs sit is the fastest way to stop paying for the same mistake twice.
What counts as a quality escape
An escape is different from a nonconformance caught in-house. A shop that finds a bad part during in-process or final inspection and holds it has a quality system doing its job. An escape is the part that got through: wrong revision, missed dimension, wrong finish, missing cert. It costs more because it’s found late, after the part has been received, kitted, or installed.
Escapes start at handoffs
Modern CNC equipment holds tolerance well when it’s programmed against the right data. The weak points sit between people and companies:
- Drawing to quote. An ambiguous callout or a missing revision letter gets read one way by the estimator and another way by the programmer.
- Buyer to shop. Requirements that live in a PO note, a spec sheet, or an email thread never make it onto the traveler.
- Shop to sub-tier. Plating, heat treat, and passivation often go to an outside processor. If the spec, class, and thickness don’t travel with the parts, the processor fills in the blanks.
- Revision changes mid-program. The drawing updates and the shop keeps running the old one. Configuration control fixes this, and it only works when someone owns it.
- Inspection to shipping. A sampling plan that’s fine for a stable process can miss a defect that only shows up on part 40 of 50.
Each of these is a place where nobody is clearly responsible for the requirement making it across the gap.
The drawing is where most escapes are seeded
Blanket tolerances, missing datums, finish callouts without a spec number, and notes like “break all edges” leave room for judgment, and judgment varies from shop to shop. A DFM review before the job is released catches most of this while it’s still free to fix. Our post on drawing callouts that raise your quote covers several of the same callouts, since the features that drive cost are often the ones that drive escapes.
Splitting work multiplies the handoffs
Every vendor you add to a build adds a handoff. A part machined at one shop, anodized at a second, and assembled at a third has three sets of paperwork and three chances for a requirement to drop. Splitting a BOM across several quick-turn manufacturing portals to save on line prices adds the same risk, with nobody tracking the whole build. We covered that tradeoff in the hidden cost of splitting a BOM across multiple portals and in where multi-process builds actually go wrong.
How to close the gaps
- Lock the revision. Put the drawing revision on the PO and require the shop to confirm it on the traveler.
- Flow down every requirement in writing. Finish specs, material certs, FAI, and special processes belong on the PO, not in a side conversation.
- Require first article inspection on new or changed parts. An AS9102-style FAI report catches setup errors before they repeat across a lot.
- Ask who verifies outside processing. Someone should check plating and heat treat certs against the spec before parts ship.
- Name one owner. When a requirement crosses a gap, one person should be accountable for it making it across.
When something still gets through, the response matters as much as prevention. Our post on who owns the fix when a part fails inspection walks through containment, root cause, and corrective action.
How PE closes the handoffs
PE is AS9100D Compliant and ISO 9001:2015, and our quality system reaches into every shop in the network. Before a job is released, an engineer reviews the drawing and flags ambiguous callouts. Requirements flow down in writing to the vetted shop and to any outside processors. The shops themselves are qualified through six checks before they get your part and matched to the process your part needs.
Parts come back to San Clemente for inspection before they ship to you, and one project manager owns the job from RFQ to delivery. Across more than 1M parts delivered, that’s how we keep dates without letting quality slide to make them. As Adam N., a senior mechanical engineer, put it: “Everything was dead on spec. Keep sending us beautiful, perfect parts early, and we’ll keep sending you our business.”
Frequently asked questions
A nonconforming part that passes through a supplier’s inspection and reaches the customer. It differs from a nonconformance caught in-house, which is exactly what a quality system is designed to catch.
Most start at handoffs: ambiguous drawings, requirements that don’t flow down to the shop or its sub-tier processors, revision changes that never reach the floor, and sampling plans that miss intermittent defects.
Lock the drawing revision on the PO, flow down every requirement in writing, require first article inspection on new or changed parts, verify outside processing certs, and assign one owner for the job.
It catches setup and programming errors before they repeat across a production lot. It won’t catch problems introduced later, like a revision change or tool wear, so it works alongside in-process and final inspection.
