How do you check FAR 117 crew duty and rest legality automatically?

AviationAlley checks FAR 117 and 121.467 crew duty-rest legality with a deterministic engine that runs line-by-line against the regulation — the same inputs always produce the same answer, and every result is defensible to an FAA inspector. The legality call is made by auditable rules, never by AI; any AI in the platform only drafts briefs and narrates scores, it never decides compliance.

FAR 117 flight, duty, and rest limits are unforgiving, and "we think it's legal" is not an answer you want to give an inspector. AviationAlley builds duty-rest legality checking directly into the crew duty board, pilot bidding, reserve, and trip-trading workflows your dispatchers and crew schedulers already use. The legality engine is deterministic and rule-based by design — not a probabilistic model — so the answer it gives is the answer you can defend. AviationAlley is pre-launch and opening to a founding cohort of operators, so the description below is what the founding-cohort build is built to do.

Why the answer is what it is

Deterministic rules, not an AI guess

FAR 117 and FAR 121.467 legality run on deterministic, line-by-line rules — the same inputs produce the same answer every time, with no black box and no probabilities. That is the opposite of asking an AI model whether a pairing is legal. The legality determination is made by code that maps directly to the regulation, so you are never trusting a statistical estimate on a compliance call.

Defensible to an FAA inspector

Because the engine evaluates the rule line by line, every legality result is one you can put in front of an inspector defending a finding. There is no 'the model said so' — there is the rule, the inputs, and the deterministic outcome. The same FAR-rule approach covers FAR 117, 121.467, FRAT, and fatigue-risk scoring, so your compliance story is consistent across the board.

Built into the crew duty board and bidding workflows

Legality checking isn't a separate audit step — it lives inside the crew duty boards, LINE and PBS bidding, reserve, and trip-trading where schedule decisions actually happen. When a bid, swap, or reserve assignment is constructed, FAR 117 / 121.467 duty-rest legality is checked by the rules engine rather than guessed at, so problems surface where they're created instead of after the fact.

AI assists never make the legality call

AviationAlley does use a few Claude-powered assists, but they are scoped tightly. A pairing optimizer can suggest up to five ways to rebalance credit-hour spread and tighten layovers — but it is advisory only and never auto-awards; the deterministic bidding engine still runs the awards. A plain-English risk explainer narrates what's driving a fatigue-risk score, but the score itself is computed by the deterministic engine. The AI drafts and explains; the rules decide.

Dispatch watch surfaces crews nearing a cap

For situational awareness, the Dispatch watch brief folds grounded tails, open MELs, weather, and crews nearing a FAR 117 cap into one plain-English 'what needs attention now' read for the dispatcher. This is a drafted brief for a human to act on — nothing is scheduled, sent, or approved on its own — so it complements the deterministic legality engine without ever substituting for it.

No half-working features in demos or offline ops

Every AI surface in the platform hides itself when no API key is set, so test centers, demos, and offline operations never meet a half-working feature. The deterministic FAR engines do not depend on that key — the legality and scoring rules run regardless — so the compliance core works the same with or without the optional AI assists turned on.

What to look for

  • Legality engine is deterministic: same inputs, same answer every time
  • Covers FAR 117 and FAR 121.467 duty-rest limits line by line
  • Results are defensible to an FAA inspector — no black box
  • Checks run inside crew duty boards, LINE/PBS bidding, reserve, and trip-trading
  • Pairing optimizer is advisory only — it never auto-awards
  • AI narrates risk scores but never makes the legality determination
  • Dispatch watch flags crews nearing a FAR 117 cap for a human to act on
  • AI surfaces hide when no API key is set; the rules engine still runs

Related questions

Does AviationAlley use AI to decide whether a pairing is FAR 117 legal?

No. The legality determination is made by a deterministic, line-by-line rules engine for FAR 117 and 121.467 — same inputs, same answer, every time. AI in the platform only drafts briefs and narrates risk scores; it never decides compliance.

Can I show the legality results to an FAA inspector?

Yes — that's the design goal. Because the engine evaluates each rule deterministically rather than estimating, every result is one you can put in front of an inspector defending a finding. There are no probabilities or black-box outputs in the compliance path.

Where do the FAR 117 checks happen in the workflow?

Inside the crew duty boards, LINE and PBS bidding, reserve, and trip-trading. Duty-rest legality is checked by the rules engine as schedules are built, and a Dispatch watch brief separately flags crews nearing a FAR 117 cap for the dispatcher to act on.

How Roffik addresses this

The platform for FAA-approved Part 142 training centers — simulator scheduling, FAA compliance records, client-account billing, and SWIFT wire reconciliation. Learn more about AviationAlley.

Keep exploring