Direct Answer
The FAA does not inspect Part 135 operators on a fixed public schedule — there is no “every six months” or “once a year” rule. Oversight runs through the FAA Safety Assurance System (SAS), a risk-based, data-supported model described in FAA Order 8900.1. Your assigned Certificate Management Team builds a surveillance plan on an annual planning cycle for Part 135, but the depth and timing of actual surveillance is weighted toward higher-risk operators and the specific areas the data flags.
That means frequency varies by operator: a newly certificated or fast-changing operator draws more attention than an established one with a clean record. And some surveillance — ramp inspections, en route checks, event-driven reviews after an accident or complaint — can happen with little or no notice. Because you cannot predict the exact timing, the only reliable strategy is continuous audit-readiness: every certificate, pilot-currency, and aircraft-airworthiness record current and retrievable on any given day.
Why There Is No Fixed FAA Inspection Interval
Operators search for a number — “how often does the FAA inspect planes,” “how often does the FAA audit a charter operator” — and expect an interval like an annual inspection on an aircraft. That number does not exist for operator surveillance, and it is important to understand why, because the absence of a schedule is itself the answer.
The FAA moved deliberately away from a one-size-fits-all surveillance schedule toward the Safety Assurance System (SAS) — a standardized, risk-based, data-supported oversight system used across Flight Standards. SAS is the FAA’s tool for certification, surveillance, and continued operational safety, and it is designed so inspectors can focus their work on the highest areas of risk rather than spreading the same effort evenly across every certificate holder regardless of risk. The procedures live in FAA Order 8900.1, Volume 10 (SAS policy and procedures) — guidance, not a regulation, and notably SAS does not impose additional requirements on certificate holders beyond what the CFR already requires.
For Part 135, SAS surveillance is planned on an annual planning cycle — your Certificate Management Team sets priorities for the year and allocates oversight resources using a data-supported, risk-based methodology. But an annual planning cycle is not the same as “one inspection per year.” The plan can include multiple assessments across operations, airworthiness, and training, it can be revised when new data arrives, and it sits alongside unannounced ramp checks and event-driven surveillance. So the real shape of FAA oversight is: a planning rhythm that is roughly annual, executed at a depth and frequency that scales with your risk profile, plus the ever-present possibility of a no-notice encounter.
A note on accuracy
Be skeptical of any source that gives you a confident “the FAA audits Part 135 operators every X months” figure. The FAA’s public materials describe oversight as risk-based and continuous and do not publish a universal surveillance interval. The annual figure that is real is the SAS planning cycle — not a promise of a single annual visit, and not a ceiling on how often an inspector can show up.
What Actually Drives Your Surveillance Frequency
Under the risk-based SAS model, these are the factors that pull surveillance toward — or, when absent, away from — your certificate. The list is qualitative on purpose: the FAA weights risk from many data sources and does not publish a fixed scoring formula.
New certificate / recent certification
Raises frequencyThe period right after a certificate is issued draws concentrated oversight — the FAA is confirming the operator runs the way its approved manuals and OpSpecs say it does.
Accident, incident, or occurrence
Raises frequencyAn accident or incident commonly triggers event-driven surveillance that is structurally identical to a planned visit — the same record domains are pulled, often on short notice.
Complaint or hotline report
Raises frequencyA complaint — including a suspected illegal-charter or grey-charter report — can prompt the FAA to look closer at operational control, authorizations, and records.
Rapid change (fleet, ops type, personnel)
Raises frequencyA new aircraft type, a new authorization or OpSpec amendment, or turnover in required management personnel changes the operator’s risk picture and can pull surveillance forward.
Prior findings / missed corrective action
Raises frequencyOpen findings or a blown corrective-action deadline keep an operator higher on the priority list until the issue is closed and the trend reverses.
Clean history, stable operations
Lowers (not eliminates) frequencyAn established operator with a clean surveillance record and steady operations tends to see oversight calibrated to a lower risk profile — but a single event can reset that quickly. Lower is not none.
The trigger does not change what the inspector asks for
Whether surveillance arrives on the annual plan, after an incident, or off a complaint, the inspector pulls the same record domains — certificate documents, per-pilot currency, and per-aircraft airworthiness. That is the strategic insight: you cannot control the trigger or the timing, but you can make the records always ready, which neutralizes every trigger at once. See the document-by-document breakdown in how to prepare for a Part 135 FAA surveillance audit and the exact list in the records an FAA inspector asks for.
You can’t schedule the FAA — so check your readiness now
The free FAA Readiness Score walks the same document domains an inspector covers and shows you which gaps would surface as findings if surveillance arrived today. No signup required; takes under 3 minutes.
Run the Free FAA Readiness ScoreThe Three Ways the FAA Shows Up — and How Much Notice You Get
“Inspection,” “audit,” and “ramp check” get used interchangeably, but they are not the same event, they carry different amounts of notice, and they have different scopes. Understanding the differences is part of understanding frequency — because each type has its own trigger and rhythm.
Planned surveillance (records & programs)
The in-depth review of your manuals, per-pilot training and check files, maintenance program, and airworthiness records. Built on the annual SAS planning cycle for Part 135 and usually arranged with the certificate holder so files and people are available.
Ramp inspection (ramp check)
A shorter check, typically at the aircraft: airman and medical certificates, the aircraft’s required documents and airworthiness, and basic operational compliance. Per FAA guidance, a Part 135 ramp inspection is more involved than a Part 91 one, and the inspector may request an en route ride-along.
Event-driven surveillance
Surveillance prompted by an accident, incident, service-difficulty trend, complaint, or significant change. It starts focused on the trigger but pulls the same underlying records as a planned audit — which is why one posture covers all of them.
For a deeper look at the spot-check format, see what to expect in a Part 135 ramp inspection and the Part 135 ramp inspection checklist. For the full records review, the Part 135 records audit-preparation checklist walks the company, pilot, and aircraft domains end to end.
Why “Always Audit-Ready” Is the Only Reliable Answer
If you cannot predict the timing, the depth, or even whether you will get notice, then any strategy built on “we’ll get ready when we hear from the FSDO” is structurally unsound. The operators who pass surveillance cleanly — planned or surprise — are the ones for whom an inspector’s arrival changes nothing, because the records were already current and retrievable. That is a documentation discipline, and it maps to three domains the inspector always covers.
Company & certificate documents — always current
Air Carrier Certificate, current Operations Specifications, and a current General Operations Manual and General Maintenance Manual. Under 14 CFR 135.21 the manual must be kept current and accessible to personnel and furnished to FAA representatives. Verify revisions match the approved content and that distribution to required personnel is documented.
Per-pilot currency — tracked with expiration alerts
Airman and medical certificates, recurring competency and proficiency checks, line checks, and recurrent training. Under 14 CFR 135.63 the operator must keep individual pilot records and make them available for inspection. Put dated-record alerts well ahead of every expiry so nothing lapses unnoticed.
Per-aircraft airworthiness — complete and retrievable
Airworthiness and registration documents, the governing inspection program and its signoffs, airworthiness-directive compliance records, and maintenance return-to-service entries. For high-utilization fleets these accumulate continuously and must be retrievable per tail on demand.
The 60-minute test — can you produce it cold?
The honest measure of readiness: if an inspector arrived unannounced this afternoon, could you produce a complete, current file for every pilot and every aircraft within the hour? If assembling that file is a scramble, surveillance frequency is irrelevant — the next visit, whenever it comes, will find the gap.
FileFlo: the proof layer that keeps you audit-ready every day
FileFlo is a compliance document intelligence platform — a proof layer that sits alongside your existing stack (flight scheduling, maintenance tracking, training software) and keeps the documents those systems produce current, complete, and instantly retrievable. It classifies over 600 document types against the governing CFR, tracks expiration windows on every medical, competency and proficiency check, recurrent-training record, and equipment inspection, and produces an inspector-format binder across all three document domains on demand. Because surveillance frequency is unpredictable, that “on demand” is the whole point.
To be clear about scope: FileFlo does not conduct the audit, represent you to the FAA, or give legal advice, and it does not replace your safety management system, dispatch/FOS, or maintenance-tracking platform. It is the records-and-proof layer that makes any required document producible the moment an inspector asks. For Part 135 on-demand charter operators specifically, it tracks the per-pilot training matrix across the whole roster and surfaces any record approaching its window — so the answer to “when is the FAA coming?” stops mattering.
Related Part 135 audit-prep reading
Frequently Asked Questions
How often does the FAA inspect a Part 135 operator?
There is no fixed public interval — the FAA does not publish a schedule that says it inspects every Part 135 operator every N months. Under the FAA Safety Assurance System (SAS), the framework described in FAA Order 8900.1, oversight is risk-based and data-supported: your assigned Certificate Management Team builds a surveillance plan on an annual planning cycle for Part 135, and the actual depth and frequency of surveillance is targeted toward the operators and the specific risk areas the data flags. A clean, established single-pilot operator and a fast-growing fleet that just added a turbojet and a new chief pilot do not receive the same amount of attention. The practical takeaway: because the trigger can be the annual plan, an event, a complaint, or a ramp encounter, the only reliable strategy is continuous readiness — every record current and retrievable on any given day.
Does the FAA inspect charter operators on a set schedule?
Not a rigid one. The FAA frames its oversight as continuous and risk-based rather than calendar-driven. For Part 135, SAS planning runs on an annual cycle, so most certificate holders see some planned surveillance activity across a year — but that is a planning rhythm, not a guarantee of a single annual visit, and it is supplemented by event-driven surveillance and unannounced ramp inspections. Newly certificated operators typically receive heavier early surveillance. Operators with recent findings, an accident or incident, rapid fleet or personnel change, or a complaint on file generally move up the priority list. So the honest answer to 'is it on a set schedule' is: the planning is annual, the execution is risk-weighted, and parts of it (ramp checks, en route checks) can happen with no notice at all.
What triggers an FAA audit or increased surveillance of a Part 135 operator?
Common triggers include: initial certification and the first period after it; an accident or incident; a service difficulty, mechanical-irregularity, or self-disclosure trend; a complaint or hotline report (including suspected illegal charter); rapid change — new aircraft type, new authorizations or OpSpec amendments, or turnover in required management personnel; prior findings or a missed corrective-action deadline; and data signals the FAA's analysts surface from the operator's own reporting. Under the risk-based SAS model, each of these raises the operator's risk profile and can pull surveillance forward or deepen it. None of these triggers changes what the inspector ultimately asks for — the same certificate, pilot-currency, and aircraft-airworthiness records — so the defense is identical regardless of what set off the visit: have every document current and produce it on demand.
Is an FAA ramp inspection the same as a Part 135 audit?
No. A ramp inspection (sometimes called a ramp check) is a short, often unannounced spot-check that typically happens at the aircraft — an inspector verifies airman and medical certificates, the aircraft's required documents and airworthiness, and basic operational compliance, using the FAA's ramp inspection job aid as a guide. A full surveillance audit under SAS is broader and more structured: it reaches into your manuals, your per-pilot training and check records, your maintenance program and airworthiness records, and your management structure. Per FAA guidance, a ramp inspection of a Part 135 flight is more involved than a Part 91 one, and an inspector may even request to ride along for an en route inspection. Both pull from the same underlying records, which is why an operator that is genuinely audit-ready passes a surprise ramp check without breaking stride.
Does the FAA give advance notice before an audit?
Sometimes yes, sometimes no — it depends on the type of surveillance. Planned, in-depth assessments of records and programs are often coordinated in advance with the certificate holder, because the inspector needs files pulled and people available. Ramp inspections and en route inspections, by design, can occur with no notice. Event-driven surveillance after an accident, incident, or complaint may also arrive quickly. Because you cannot count on a warning, the only durable posture is one where advance notice would not change anything: the binder is already complete. Operators who treat audit prep as a fire drill triggered by a phone call are the ones who get caught with an expired check or a manual revision that was never distributed.
How often does the FAA inspect newly certificated Part 135 operators versus established ones?
New certificate holders generally receive more concentrated early oversight. The certification process itself is intensive, and the period immediately after a certificate is issued is when the FAA is confirming the operator actually runs the way its approved manuals and OpSpecs say it does. Established operators with a clean surveillance history and stable operations tend to see oversight calibrated to their lower risk profile under the SAS model — but 'lower' is not 'none,' and a single event (an incident, a complaint, a key-personnel change, a new aircraft type) can reset that calculus quickly. The risk-based model is dynamic, not a fixed tier you graduate into permanently.
What does the FAA actually look at when it audits a Part 135 operator?
Across surveillance events, FAA inspectors work through three document domains. Company/certificate level: the Air Carrier Certificate, current Operations Specifications, and a current General Operations Manual and General Maintenance Manual kept current and available to FAA representatives under 14 CFR 135.21. Per-pilot level: airman and medical certificates, recurring competency and proficiency check records, line checks, and recurrent training — the operator must keep individual pilot records and make them available for inspection under 14 CFR 135.63. Per-aircraft level: airworthiness and registration documents, the inspection program and signoffs, airworthiness directive compliance records, and maintenance/return-to-service records. The recurring theme in surveillance findings is documentation: a record that is missing, expired, or not retrievable, even when the underlying flying and maintenance were done correctly.
How can a Part 135 operator stay ready for an FAA audit at any time?
Treat readiness as a continuous state, not a pre-audit project. Practically: maintain a single organized system covering the three document domains (company, per-pilot, per-aircraft); put expiration tracking on every dated record — medicals, competency and proficiency checks, line checks, recurrent training, and equipment inspections — with alerts well before anything lapses; verify manual revisions are current and that distribution to required personnel is documented; and keep maintenance return-to-service and airworthiness-directive records complete and instantly retrievable. The test is simple: if an inspector arrived unannounced this afternoon, could you produce a complete, current file for every pilot and every aircraft within the hour? FileFlo is built to make that answer 'yes' — it is the compliance document layer that keeps every record current and retrievable. It does not conduct the audit, represent you to the FAA, or replace your safety, dispatch, or maintenance-tracking systems.
Stop guessing when the FAA will show up — be ready every day
FileFlo keeps every document across the three inspector domains — company certificate, per-pilot currency, and per-aircraft airworthiness — current and retrievable, and generates a complete audit binder on demand. Starter plan at $89/month. Professional at $299/month (unlimited pilots + aircraft). Five-day free trial, no credit card required.
5-day free trial · No credit card required · Cancel anytime · FileFlo is the proof layer that keeps records audit-ready — it does not conduct the audit, represent you to the FAA, or replace your SMS, dispatch, or maintenance-tracking system.