Skip to content

Hard-time intervals

Hard-time component status review

A hard-time component status review confirms that each component managed under a hard-time limit carries the correct overhaul or replacement interval, a supported last-accomplished reference, and a correctly calculated next-due, with shop and release evidence behind it. It is used by lessors, airlines, and acquisition teams when interval-driven removals affect cost, value, or a return condition. It reviews the hard-time status list, the maintenance program intervals, shop-visit reports, and release certificates. You receive a component-by-component status with next-due calculations and a list of interval, last-done, or evidence discrepancies.

When this review is needed

  • A hard-time status list drives near-term removal cost and is being relied on for a return, lease, or sale without a check against shop evidence.
  • An aircraft is changing maintenance programs and the hard-time intervals have to be re-mapped to the receiving program.
  • A component shows a next-due that is close and the last-overhaul reference and interval need confirming.
  • A component was overhauled at a shop visit and the release evidence and reset zero-time need verifying.

The problem

Hard-time status is delivered as a list of components, each with an interval and a next-due. The next-due is a calculation off a last-done reference and the governing interval, and both can be wrong: an interval carried over from a different program, a last-overhaul date taken from the wrong shop visit, or a hard-time item that has quietly migrated to on-condition without the records following. None of that is visible on the status list alone.

What gets reviewed

  • Each hard-time component by part number and serial number against its governing interval
  • The interval source reconciled to the applicable maintenance program
  • Last-overhaul or last-replacement reference and the shop visit that set it
  • Next-due calculation in hours, cycles, or calendar as the limit requires
  • Release evidence and zero-time reset at the last hard-time accomplishment
  • Components whose management basis changed between hard-time and on-condition
  • The hard-time status list reconciled against the shop and release records

Scope this review

Tell us the asset, the event, and the evidence in scope, and we will outline a focused first engagement.

Send a representative, redacted record set and we will scope the review.

What gets validated

  • Each component's governing interval matches the applicable maintenance program in effect
  • The last-accomplished reference ties to the shop visit and release that performed the overhaul
  • Next-due is recomputed and consistent across hours, cycles, and calendar where multiple apply
  • A zero-time reset after overhaul is supported by the release certificate for that visit
  • Serial numbers on the status list match the components actually installed
  • Any change between hard-time and on-condition management is reflected with its program basis
  • The status-list figures reconcile with the shop and release records behind them

Evidence normally required

  • Hard-time component status list with intervals and next-due figures
  • Applicable maintenance program or task-interval source
  • Shop-visit and overhaul reports for the last accomplishment of each item
  • Release certificates establishing zero-time after overhaul or replacement
  • Component installation records confirming serial numbers in service

Common discrepancies

  • An interval carried over from a prior program that does not match the current one
  • A next-due calculated from the wrong last-overhaul reference or the wrong baseline
  • A zero-time reset claimed at overhaul without a supporting release certificate
  • A component still listed as hard-time after the program moved it to on-condition
  • A serial number on the list that does not match the component installed
  • Status-list next-due figures that disagree with the shop records behind them

What is at stake

An understated next-due forces an early, unplanned removal and the cost that comes with it. An overstated next-due lets a component run past its hard-time limit, which is a compliance and airworthiness problem. Either error distorts the maintenance cost the asset is priced and leased against.

Move from findings to resolution

Move from findings to a documented resolution path.

How the work runs

01

Confirm the interval

Reconcile each component's governing interval to the applicable maintenance program and identify any carried over from a prior program.

02

Anchor the last-done

Tie the last-accomplished reference to the shop visit and release that performed it, confirming any zero-time reset.

03

Recompute next-due

Recalculate next-due in hours, cycles, and calendar as the limit requires and flag items that are overdue or wrongly based.

04

Report and route

Deliver the component-by-component status, list interval and evidence discrepancies, and identify the record needed to close each.

What the buyer receives

  • A component-by-component hard-time status with interval, last-done, and next-due
  • Recalculated next-due figures with the basis and units shown
  • A list of interval, last-done, reset, and evidence discrepancies
  • A closure path for each disputed item with the supporting record identified

Who uses the output

  • Continuing-airworthiness teams confirming removal planning and compliance
  • Asset and acquisition teams pricing near-term hard-time cost into a deal or return
  • Records teams re-mapping hard-time intervals onto a new maintenance program

How the work fits into the transaction or program

The review tests the interval-driven side of the component picture and complements the on-condition component status review, where management is by inspection rather than by fixed interval. Together they cover how each component is governed.

Jurisdiction-specific considerations

Hard-time intervals derive from the approved maintenance program, which sits under the operator's authority. When an aircraft moves between authorities, intervals are re-mapped to the receiving program, and a last accomplishment evidenced on one authority's release is checked for whether the receiving program recognizes the reset.

Regulatory limits

The review confirms that hard-time intervals, last-done references, and next-due figures are correct and supported. It does not set maintenance intervals, approve a maintenance program, make an airworthiness determination, or guarantee an authority's acceptance of the status.

What this review does not cover

  • Performing any overhaul, replacement, or inspection
  • Setting or approving a maintenance-program interval
  • Any airworthiness determination on component status

Specific to this review

  • A hard-time limit mandates removal at a fixed interval regardless of condition, so the entire status rests on the interval and the last-done reference being correct.
  • Overhaul of a hard-time component resets it to zero time, so the reset and its supporting release certificate are decisive for the next-due calculation.
  • Components can migrate between hard-time and on-condition management as the maintenance program evolves, and the records sometimes lag the change.
  • The governing interval comes from the approved maintenance program, so re-mapping is required whenever the program changes rather than treating the interval as a fixed property of the part.

Sources

Frequently asked questions

What is the difference between hard-time and on-condition management?

A hard-time component is removed at a fixed interval whatever its condition. An on-condition component stays in service while inspection shows it meets the standard. The review checks that each component is recorded under the basis the program actually assigns it.

Relevant glossary terms

Related pages

Where this fits

Talk to an engineer who has done this work

We will walk through your current state, the records or evidence involved, and a scoped first engagement.

Walk through your situation with an engineer who has done this work.