AD/CESSNA 207/40 - Alternate Static Air Source Selector Valve Placard

The central concept is the alternate static air source selector valve and the part number identification placard affixed to it. The valve selects between the normal static pressure port and an alternate source. If the placard obstructs the port, the static pressure system may deliver incorrect pressure to the instruments. The directive distinguishes between aeroplanes not equipped for IFR and aeroplanes equipped for IFR. IFR equipment means the aircraft is certified and fitted for flight solely by reference to instruments, typically with dual navigation and communication gear and a functioning static system. The distinction matters because an IFR aircraft can still be flown under visual flight rules (VFR) without using the alternate static source, but the placard option imposes a prohibition on IFR flight and on using the alternate source. Compliance time is defined in terms of time-in-service (TIS) and calendar months. TIS means hours flown since manufacture, overhaul or last inspection; the directive uses this to tie the inspection to existing maintenance schedules, albeit with a four-month cap. Before further flight means the action must be completed before the next flight after the effective date or after the event triggering the requirement. The directive also introduces the concept of replacement valve control: after ten days from effective date, only inspected and unobstructed P/N 2013142-18 valves may be installed. This imposes a supply-chain duty on maintenance organisations and parts distributors. A subtle but important concept is that AD/CESSNA 207/39 compliance immunises the aeroplane from this new directive if the modification or rework under that earlier directive has been done and the aeroplane remains in compliance. That creates a two-track compliance world: those that did AD 207/39 properly are not affected; those that did not, or that have a replacement valve shipped later, are captured. The directive thus operates as a safety net for aircraft that escaped the earlier directive or that received replacement parts from a certain distribution window (1 January 1993 to 31 March 2008). The background notes that the FAA has received 15 reports of aeroplanes not previously affected by FAA AD 2008-10-02 that still had obstructed ports, indicating that the prior directive did not catch all instances.

The directive primarily affects owners, operators and maintainers of Cessna 207, 207A, T207 and T207A aeroplanes that were delivered from the manufacturer between 1 January 1993 and 31 March 2008, or that have had a P/N 2013142-18 alternate static air source selector valve installed as a replacement part at any time after 1 January 1993. The critical carve-out is for aeroplanes that have had the modification or rework required in AD/CESSNA 207/39 done and remain in compliance with that directive. That carve-out affects roughly 15 aircraft identified by the FAA as still having the problem, but the exact population is unknown because CASA states it has no way to determine which aeroplanes have the remaining affected valve assemblies without inspecting every aircraft and spare stock. The directive therefore affects all Cessna 207 series aeroplanes in Australia that fall within the delivery or replacement window and that cannot prove compliance with AD 207/39. That population likely includes charter operators, aerial work operators (mustering, survey, parachute dropping), flying schools and private owners. The distinction between IFR-equipped and non-IFR-equipped aircraft creates different compliance timelines and options, so it affects aircraft engineers and maintenance facilities that must perform the inspection and, where required, fabricate and install placards. Parts distributors and maintenance organisations that hold P/N 2013142-18 valves in stock are affected by the replacement valve requirement: after 10 days from effective date, they cannot supply or install such a valve unless it has been inspected and found free of obstruction. This imposes a one-time inspection burden on inventory. The directive also indirectly affects insurance companies that may require proof of AD compliance before underwriting hull or liability coverage, and prospective buyers of affected aircraft who will need to verify compliance before purchase. For the regulator (CASA), the directive is an administrative and enforcement burden: it must monitor compliance, respond to reports, and potentially issue further directives if the inspection reveals widespread obstruction. For the aircraft owners, the direct cost is the labour time for inspecting the valve, which may range from a few minutes to an hour, plus any required placard fabrication and installation. The opportunity cost is aircraft downtime, particularly for IFR operators who choose the placard option and then have to do a second visit for inspection and placard removal. The directive imposes a compliance cost that does not improve aircraft performance or utility; it merely reduces a known risk.

The directive imposes the following specific duties, which vary by aircraft type and operator choice. For non-IFR equipped aeroplanes, the duty is to inspect the alternate static air source selector valve to assure the part number identification placard is not obstructing the port. This must be done within the earlier of 100 hours time-in-service or four months after the effective date. For IFR-equipped aeroplanes, the operator has a right to choose between two compliance paths. Path A is to inspect the valve within ten days after the effective date. Path B is, before further flight after the effective date, to fabricate and install a placard on the instrument panel within the pilot’s clear view stating “IFR OPERATION IS PROHIBITED” and “USE OF THE ALTERNATE STATIC AIR SOURCE IS PROHIBITED.” If Path B is chosen, the operator then has a subsequent duty: within 100 hours TIS or four months, inspect the valve, and after that inspection, remove the placards before further flight. For both paths, if the inspection reveals the port is obstructed by the placard, the operator must remove the placard from the valve body, discard it, and assure the port is open and unobstructed. That last step must be done before further flight after the inspection. Additionally, for all affected aeroplanes, once a replacement valve is needed at any time after ten days from the effective date, the duty is to only install a P/N 2013142-18 valve that has been inspected and found free from obstruction. This duty falls on whoever performs the replacement, typically a licenced aircraft maintenance engineer or the operator under a maintenance approval. The directive does not create any rights for the operator to seek reimbursement from Cessna, the distributor or CASA; the cost of compliance is borne entirely by the aircraft owner. The operator does have the right to delegate the physical work to an appropriately authorised person, but the ultimate responsibility for compliance rests with the registered operator. The directive also implicitly creates a right to rely on the service bulletins listed (Cessna Single Engine Service Bulletin SB08-34-02 Revision 1, Cessna Caravan Service Bulletin CAB08-04 Revision 1, etc.) as the approved method of compliance, though the directive does not mandate their purchase or use; it merely says the procedures are detailed in those bulletins. The operator has no right to ignore the directive or to substitute an alternative method of compliance without CASA approval, which is not mentioned in the directive itself.

The directive itself does not state penalties, but as a CASA-issued airworthiness directive under the Civil Aviation Act 1988 (Cth) and Civil Aviation Regulations 1988, noncompliance is a serious breach. Operating an aircraft that does not comply with an applicable airworthiness directive is likely an offence under regulation 42ZC of the Civil Aviation Safety Regulations 1998 (CASR), which prohibits operating an aircraft that does not meet its airworthiness requirements. Penalties for individuals can include fines of up to 100 penalty units (currently $31,300) or imprisonment for two years, or both, per breach. For bodies corporate, fines can be up to 500 penalty units ($156,500) or more. Additionally, CASA can suspend or cancel an aircraft’s certificate of airworthiness or a maintenance organisation’s approval. The directive carries specific deadlines that trigger immediate enforcement risk: for example, failure to inspect an IFR aircraft within ten days of the effective date, or failure to remove placards before flight after the later inspection, could result in the aircraft being unairworthy. The directive’s practical enforcement mechanism is that the aircraft’s maintenance release or logbook entry will need to show compliance; a sale or annual inspection would typically require proof of directive compliance. CASA may conduct ramp checks or audit maintenance records; an inspector finding noncompliance could issue a direction to ground the aircraft or a notice of proposed enforcement action. The directive also creates a chain of liability: if a maintenance engineer installs a replacement valve that has not been inspected (contrary to Requirement 5), both the engineer and the operator could face enforcement. The Australian Transport Safety Bureau could also investigate any incident involving instrument failure linked to the noncompliant valve, potentially leading to criminal prosecution for reckless operation. For an operator, the economic penalty of being grounded far outweighs the fine, particularly for charter or aerial work operators who lose revenue during downtime. The directive effectively uses the threat of grounding and legal sanctions to compel a low-cost inspection; any operator who delays compliance faces not only legal risk but also an uninsurable aircraft if an incident occurs.

This directive operates within a hierarchy of aviation safety regulation. It is issued under the authority delegated by CASA under the Civil Aviation Act 1988 and the Civil Aviation Regulations 1988 / Civil Aviation Safety Regulations 1998. It specifically references FAA AD 2008-26-10 Amdt 39-15776, which is the United States Federal Aviation Administration’s equivalent airworthiness directive. CASA often adopts FAA directives for type-certificated aircraft, but this directive is a standalone Australian AD, not a direct adoption; it has its own effective date and specific compliance requirements. The directive notes that it was prompted by AD/CESSNA 207/39, which itself responded to FAA AD 2008-10-02. The interaction creates a compliance chain: an aeroplane that has fully complied with AD 207/39 and remains compliant is exempt from this AD. An aeroplane that has not, or that has had a replacement valve installed later, must comply with this AD. The directive also references Cessna Single Engine Service Bulletin SB08-34-02 Revision 1, Cessna Caravan Service Bulletin CAB08-04 Revision 1, Cessna Single Engine Service Bulletin SEB08-5, and Cessna Multi-engine Service Bulletin MEB08-6 as the procedures to accomplish the required inspection and placard removal. Those service bulletins are not regulatory instruments but are manufacturer recommendations; the AD makes compliance with them mandatory. In terms of interaction with other Australian laws, the directive must be read with regulation 42ZC of CASR, which requires that an aircraft must be maintained in an airworthy condition and must comply with all applicable ADs. The directive also interacts with the operator’s maintenance program: compliance must be recorded in the aircraft logbook or maintenance release, and the inspection intervals (100 hours TIS or 4 months) align with typical periodic inspection cycles. The directive does not override any other AD; if an aircraft has multiple ADs affecting the same component, both must be complied with. The directive also has implications for import and export: an Australian-registered aircraft operating overseas must still comply with the AD, and a foreign aircraft operating in Australia may be subject to reciprocal recognition of ADs under bilateral agreements. The directive does not interact with tort law as such, but a failure to comply that causes injury could be evidence of negligence in a civil claim.

This directive, AD/CESSNA 207/40, is a single issuance. The document is dated 8 January 2009 and becomes effective on 16 January 2009. There is no indication in the source of any subsequent amendments, revisions, or supersedures. The directive itself references its predecessor, AD/CESSNA 207/39, which was issued in response to FAA AD 2008-10-02. AD 207/39 addressed the same P/N 2013142-18 valve placard issue but apparently did not capture all affected aircraft; CASA and the FAA found 15 additional aeroplanes with the obstructed port after that directive was issued. The background explains that CASA has no way to determine which aeroplanes have the remaining problem valve assemblies without inspecting all affected aircraft and spares stock. Therefore, AD 207/40 expands the applicability to include aeroplanes delivered between 1 January 1993 and 31 March 2008, and also any aeroplane that had a P/N 2013142-18 valve installed as a replacement part after 1 January 1993, regardless of whether it was covered by AD 207/39. The earlier directive remains in effect for those aircraft that complied with it; those aircraft are exempt from this directive. The amendment history is thus essentially a loop: AD 207/39 attempted to fix the problem, AD 207/40 broadens the net. There is no mention of any subsequent AD superseding AD 207/40. For an operator or maintenance engineer, the history means they must check whether the aircraft has AD 207/39 compliance recorded; if not, they must comply with AD 207/40. If the aircraft has AD 207/39 compliance, they must verify that it remains in compliance (e.g., no subsequent replacement valve has been installed without inspection). The practical effect is that a careful owner should have records of compliance with both directives, and if the aircraft was delivered after 31 March 2008, it is not affected by this directive unless a replacement valve from the suspect distribution window was installed later.

The source document contains no reference to any litigation, court cases, tribunal decisions, or administrative review proceedings related to this specific airworthiness directive. This is consistent with the nature of airworthiness directives, which are rarely litigated directly. Operators may challenge a directive in the Administrative Appeals Tribunal or federal courts under grounds of jurisdictional error, unreasonableness or improper delegation, but such challenges are uncommon and typically unsuccessful because courts give wide deference to aviation safety regulators on technical matters. There is no recorded case law in Australia on AD/CESSNA 207/40 itself. The directive’s background references the FAA’s AD 2008-10-02 and AD 2008-26-10; there may have been US litigation regarding those FAA directives, but it is not cited here. In the United States, airworthiness directives are occasionally challenged by general aviation groups or owners on cost-benefit grounds, but the outcomes are rarely publicised. For Australian operators, the litigation risk is not that they will sue CASA but that they will face enforcement action for noncompliance, which could be litigated in the Federal Circuit Court or the Administrative Appeals Tribunal. The practical litigation history for this directive is likely limited to a few informal disputes between operators and CASA inspectors over compliance time extensions or the interpretation of “equipped for flight under IFR.” The directive’s definition of IFR equipment is not spelled out, which could be a source of contention: does a aircraft with a single VOR and no autopilot count as IFR-equipped? The directive does not define it, leaving operators to rely on the aircraft’s certification and equipment list. That ambiguity may lead to disagreement but not formal litigation. In sum, the litigation history for AD/CESSNA 207/40 is effectively a blank page; the directive has operated without legal challenge, likely because the compliance cost is low and the safety rationale is clear.

Several traps in this directive can catch unwary operators and engineers. First, the exemption for aircraft that have complied with AD 207/39 is conditional: the aeroplane must remain in compliance with that AD. If, after AD 207/39 compliance, anyone installed a replacement P/N 2013142-18 valve from the suspect distribution window without inspection, the exemption is lost. An operator who thinks they are compliant may actually be required to comply with AD 207/40. Second, the compliance deadline for IFR aircraft that choose the placard route (Requirement 2b) is “before further flight after the effective date of this AD.” That means the placard must be installed before the aircraft is flown on or after 16 January 2009. If an operator does not read the directive until after 16 January, they may have already flown IFR in violation. Third, Requirement 3 creates a paradoxical sequence: for IFR aircraft that installed placards under 2b, they must inspect the valve within 100 hours or 4 months, and after that inspection, remove the placards before further flight. The removal of the placards must happen before the next flight after the inspection, but the placards stated “IFR OPERATION IS PROHIBITED” - removing them after a successful inspection implies the aircraft is now cleared for IFR, but only if the inspection was satisfactory. If the port is found obstructed, the operator must follow Requirement 4 (remove placard from valve body) before further flight, and then the aircraft cannot be flown IFR until a new valve is installed? The directive does not explicitly say the aircraft returns to IFR service after a successful inspection and placard removal; logically it does, but the directive’s wording is ambiguous. Fourth, Requirement 5 says “when a replacement valve is needed, only install a P/N 2013142-18 ... that has been inspected and the port is found free from obstruction.” This applies “as of 10 days after the effective date.” After that date, any valve in stock that has not been inspected may not be installed. An engineer who installs a valve from inventory without verifying inspection status is in breach, even if the valve was originally shipped before the suspect window. Fifth, the directive requires the placard text to be “at least 1/8-inch letters.” A placard with smaller text would be noncompliant, potentially invalidating the entire placard option. Sixth, the directive says the placard for IFR prohibition must be installed “on the instrument panel within the pilot’s clear view.” If the panel is crowded, attaching a substantial placard may be difficult, and the placard may obscure other instruments, creating a secondary hazard. Seventh, the directive does not specify what constitutes an “IFR-equipped” aeroplane. An aircraft might have a partial IFR panel but not be legally certificated for IFR; taking the inspector’s view could trigger unnecessary additional actions. Eighth, the service bulletins referenced (SB08-34-02, etc.) may contain additional procedural details not in the directive; operators who rely solely on the directive text may miss steps.

Compliance requires a methodical approach based on the aircraft’s status. Step 1: Determine applicability. Check the aircraft model (207, 207A, T207, T207A). Check the delivery date: if delivered between 1 January 1993 and 31 March 2008, the aircraft is affected unless it has complied with AD 207/39 and remains in compliance. Also check whether any P/N 2013142-18 valve has been installed as a replacement at any time after 1 January 1993; if so, the aircraft is affected unless the AD 207/39 exemption applies. Review the aircraft’s maintenance records for AD 207/39 compliance and any subsequent valve replacements. Step 2: Determine IFR equipment status. If the aircraft is not equipped for IFR, the requirement is an inspection of the alternate static air source selector valve within the earlier of 100 hours TIS or 4 months from 16 January 2009. If the aircraft is IFR-equipped, decide whether to inspect within 10 days (Path A) or install placards before further flight (Path B). Step 3: For Path A (IFR aircraft inspect within 10 days): Schedule maintenance to inspect the valve within 10 days after 16 January 2009. Use the applicable service bulletin as the procedure. If the valve port is unobstructed, record compliance and no further action needed. If obstructed, follow Step 5. Step 4: For Path B (IFR aircraft install placards): Before the next flight after 16 January 2009, fabricate a placard with text “IFR OPERATION IS PROHIBITED” and “USE OF THE ALTERNATE STATIC AIR SOURCE IS PROHIBITED” in letters at least 1/8-inch high. Install it on the instrument panel within the pilot’s clear view. Then, within 100 hours TIS or 4 months, inspect the valve. After the inspection, remove the placards before further flight. If the port is obstructed, proceed to Step 5. Step 5: If inspection finds obstruction: Remove the part number identification placard from the valve body. Discard it. Verify the port is open and unobstructed. This must be done before further flight after the inspection. Step 6: For replacement valves: After 26 January 2009 (10 days after effective date), do not install any P/N 2013142-18 valve unless it has been inspected and the port found free from obstruction. Maintain records of such inspection. Step 7: Documentation. Make entries in the aircraft’s maintenance release or logbook stating compliance with AD/CESSNA 207/40, referencing the service bulletin used, the date, and the inspection result. Retain records indefinitely. Step 8: Inventory management. If you hold spare P/N 2013142-18 valves, inspect them for obstruction and mark them as compliant, or quarantine them until inspected. Step 9: For operators with multiple aircraft: Create a compliance schedule to manage differing deadlines. Use a spreadsheet to track TIS hours and calendar dates. Ensure placards are not left installed beyond the required period. Step 10: Stay current. Monitor CASA’s website for any revisions or supersedures to this directive. If in doubt, consult a licenced aircraft maintenance engineer or CASA’s airworthiness office. The cost of compliance is low compared to the risk of enforcement, but the administrative burden can catch out those who rely solely on memory.