SYSTEMS DETECTIVE · PIPER CHEROKEE 180 · Educational · SYNTHETIC CASE

The airspeed that would not settle.

One instrument reads wrong in a climb. Four causes could explain it, and every one of them leaves a different trail across the panel. Request observations, look at the parts in the Aircraft Atlas, test a hypothesis, then commit to a diagnosis. The case shows its evidence either way, and admits when you have not gathered enough.

Open the case How the detective works

Original schematic of the Cherokee 180's arrangement as the Atlas describes it: one mast under the left wing carries the ram opening and, on its underside, the static hole; pitot pressure reaches one instrument, static pressure all three.

01 / THE CASE FILE · Synthetic symptom set

FIXED FOR THE WHOLE INVESTIGATION

The airspeed that would not settle

Briefing

What you notice, and what stays true all the way through

02 / THE INVESTIGATION

OBSERVE · INSPECT · TEST · PROPOSE

Gather the evidence, then commit.

An observation costs one step and reveals what the airplane is really doing. Inspecting a part is free and opens its entry from the Atlas. Testing a hypothesis costs one step and tells you what the evidence so far says about it. Proposing a diagnosis closes the case.

Case open0 steps0 of 5 observations requested

Observations

Components

Each entry is the Aircraft Atlas's published description of that part, with a deep link to it.

Hypotheses

04 / HOW THE DETECTIVE WORKS

A FIXED CAUSAL GRAPH, NOT AN IMPROVISED ANSWER

The answer was fixed before you arrived.

The case is a small causal graph written down in advance: a handful of causes, a handful of observations, and the value every observation takes under every cause. The engine reveals an observation's value under the case's hidden answer and never changes anything, so the symptoms cannot drift and no examiner improvises.

The evidence rules

An observation supports a cause when the cause predicts exactly that value and at least one other cause predicts something else.
It separates nothing when every cause predicts the same value.
It contradicts a cause when the cause predicts a different value.
A diagnosis is supported only when it is the single cause consistent with everything observed, contradicted when an observation rules it out, and unresolved when it fits the evidence but so does a rival, in which case the result names the observations that would have separated them.

Built to take more cases

The engine (cherokee/detective-engine.js) knows nothing about this airplane; the case file (cherokee/cases/pitot-static-climb.json) carries everything, is validated on load, and must be solvable: the answer has to be separable from every other cause by at least one observation. A future case is another file.

About the examiner

The verdicts and the debrief above are computed, not generated. The page exposes its state for a future examiner in the site's Ask layer, which could explain the evidence in more words but could not change a value, a verdict or the hidden answer. There is no such examiner on this page yet, so there is no button for one.

05 / SOURCES & PROVENANCE

THE ATLAS PACK AND ITS DOCUMENTS

Sources & provenance 4 documents · one synthetic case

Synthetic: the case's symptoms, setting, timeline and assumed configuration were authored for this exercise. Published: every behaviour the case relies on (what a blocked pitot, a blocked drain, a blocked static hole, water in the line and the alternate static source each do) is the Aircraft Atlas's Cherokee 180 pack, which cites the documents below. Nothing here is maintenance or operating guidance for any aircraft.

Spotted an error, or have a document that settles a claim? Sources / suggest a correction

Documents

ABOUT SYSTEMS DETECTIVE

Educational. A synthetic case on a published system description, with a fixed answer and computed verdicts. It teaches a habit of evidence, not a procedure for any airplane; the airplane's approved manuals and a mechanic decide what to do about a real indication.

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