Eyrix — Blog

Blog

Constraint-based planning — asset-constrained scheduling and manufacturing & supply.

• Aircraft utilisation for regional & ACMI operators: 5 gaps that quietly erode it

  Five concrete gaps that drag down aircraft utilisation at small operators, and how to spot them before they show up in the block-hour numbers.

• Block-hour charter agreements: how ACMI billing actually works

  A block-hour charter agreement bills for flight hours, not flights — and that changes what actually needs to be planned for. What block-hour billing means in practice.

• Charter and ACMI flight scheduling: why it's harder than a fixed timetable

  Charter and ACMI operators re-plan constantly against a fleet that never sits still. Why ad-hoc scheduling is harder than a scheduled airline's timetable, and what a solver changes.

• Crew scheduling software: what a spreadsheet roster really costs

  Why a manual crew roster in a spreadsheet quietly erodes utilisation and compliance at small airlines — and what crew scheduling software changes.

• Crew type-ratings and rostering: matching the right crew to the right tail

  Type-ratings, recency and currency decide who may operate which aircraft. Why qualification is the constraint that quietly shrinks a roster, and what crew rostering software checks.

• EASA FTL in practice: the rest and duty limits your roster has to respect

  A plain-language map of the EASA flight time limitations a crew roster has to respect — flight duty period, minimum rest, WOCL and cumulative limits — and why a spreadsheet can't check them.

• FEFO and batch traceability: build it into the plan, not after the fact

  In regulated production, traceability is a condition of being allowed to produce. Why FEFO and lot origin belong in the planning model itself — not reconstructed when the auditor asks.

• Finite capacity scheduling: why your ERP plans against capacity you don't have

  Classic MRP backschedules as if your lines have infinite capacity. What finite capacity scheduling checks instead — and why the overload only shows up on the floor if you don't.

• The make-or-buy decision in production planning: stop deciding by gut feel

  The make-or-buy decision is usually made on experience, not a worked comparison. Why the real question is which split is feasible and cheapest — and how to answer it.

• Tail assignment planning: building aircraft rotations that actually close

  Tail assignment is more than picking an available aircraft — the rotation has to close in space and time. Where manual tail assignment breaks, and what an engine checks.