AD/CESSNA 207/39 - Alternate Static Air Source Valve

The AD centres on a specific component: the alternate static air source selector valve, P/N 2013142-18, which replaced earlier part numbers 2013142-9, -13 and -17. This valve is part of the aircraft’s static pressure system, which supplies ambient air pressure to flight instruments including the altimeter, airspeed indicator and vertical speed indicator. The alternate static air source is a backup system that can be selected if the primary static port becomes blocked. The valve itself contains a port, which is an opening on the forward end that serves as the inlet for static air reference into the valve.

The defect is that the part number identification placard (a label that displays the part number for identification purposes) was installed on the valve body in a position that physically covers this port. The placard is a small metal or plastic tag, typically attached by adhesive or a mechanical fastener. When it covers the port, it blocks or restricts the flow of static air into the valve, potentially causing the altimeter, airspeed and vertical speed indicators to display erroneous indications. The source states this could cause the pilot to react to incorrect flight information and possibly result in loss of control.

The AD creates a two-tiered inspection system. The first tier is a records-based determination: the operator checks maintenance records to see if a P/N 2013142-18 valve was installed after 19 November 2007. This can be done by any person holding at least a private pilot’s licence. The second tier is a physical inspection of the valve itself, which must be performed by a qualified person (likely a licensed aircraft maintenance engineer, though not explicitly stated). The physical inspection procedure is specific: adjust both pilot and copilot seats fully aft, then use a flashlight and mirror to visually check that the port is not covered. This suggests the valve is located in a position on the cockpit floor or sidewall that is difficult to see directly.

The AD also introduces a "pre-installation inspection" requirement: any P/N 2013142-18 valve installed on or after the effective date must be inspected for placard obstruction before installation. This imposes a duty on anyone installing such a valve (whether as a replacement or modification) to verify the placard is correctly positioned. The note in the AD confirms that all parts held in stock at Cessna have been corrected, but it acknowledges that Cessna could not verify how many assemblies were already in the field. This creates uncertainty: an operator who holds a spare valve from before the correction may need to inspect that spare before use. The concept of "before further flight" compliance is a standard aviation safety mechanism but carries significant economic weight because aircraft that are not in compliance must be grounded immediately.

The primary group affected is owners and operators of Cessna 207 series aeroplanes with any serial number. This includes commercial operators using the Cessna 207 for charter, freight, skydiving, or utility operations, as well as private owners. The Cessna 207 is a single-engine, high-wing aircraft commonly used in remote areas, for aerial work, and by small regional airlines. Operators who rely on these aircraft for revenue generation face immediate grounding risk if they cannot comply before the next flight after 13 May 2008. The cost of non-compliance is not just a fine but the inability to operate, which can cascade into lost revenue, stranded passengers or cargo, and breach of contract.

Maintenance providers are also directly affected. Licensed aircraft maintenance engineers (LAMEs) or authorised maintenance organisations will need to perform the physical inspections for operators who choose that route or who have an affected valve. This creates a surge in demand for inspections around the effective date, potentially causing delays and higher prices. The AD allows an operator with at least a private pilot’s licence to perform the records check under Requirement 1.b, which may reduce demand for maintenance services for that specific step. However, the physical inspection still requires a qualified person, and the removal of the placard (if needed) is a maintenance action that may require a LAME or be done under supervision.

Cessna (the manufacturer) is indirectly affected: the AD highlights a quality control failure in its production process. The company had to correct parts held in stock, but the field remains exposed. This may lead to reputational harm, potential warranty claims, or product liability exposure. The AD does not require Cessna to bear any cost for the inspections, so the financial burden falls entirely on operators.

Parts suppliers and distributors are also affected. Anyone holding a P/N 2013142-18 valve in stock that was manufactured between 20 November 2007 and 18 February 2008 may need to inspect those parts before selling or installing them. The AD imposes a strict liability: if a valve with the placard obstructing the port is installed, the installer and operator may be non-compliant. This means suppliers need to ensure their inventory is clear, or they risk passing defective parts to customers.

Finally, the Civil Aviation Safety Authority itself is affected in terms of enforcement resources. CASA must ensure compliance, which may involve audits, spot checks, and processing of AD compliance records. The CASA delegate who signed the AD is James Coyne. The background notes that CASA varied the FAA inspection requirements to allow the records-based option, showing that CASA considered compliance burden. However, the variation does not reduce the ultimate requirement if the records show the affected valve was installed. It only reduces compliance cost for operators whose records show no affected valve was ever fitted.

The core duty is to inspect the affected valve or its maintenance records before further flight after 13 May 2008. This duty rests on the operator of the aircraft. The operator must make a decision: either physically inspect the valve or check the maintenance records. If the records check reveals no installation of P/N 2013142-18 after 19 November 2007, the duty is satisfied. If the records check is inconclusive or shows the valve was installed, the duty escalates to a physical inspection.

The operator has the right to choose the records-based approach, and that choice can be executed by any person holding at least a private pilot’s licence. This is a significant concession, as it allows a pilot to review logs without needing a maintenance engineer. However, the pilot must be competent to interpret maintenance records, and the AD does not specify the required level of detail. If the records are incomplete, the operator may have to fall back on physical inspection.

Once the physical inspection is performed, the duty is to confirm that the port on the forward end of the valve is clearly visible and not covered by the placard. If the port is obstructed, the placard must be removed and discarded. The duty then becomes to ensure the port is open and unobstructed before further flight. The AD does not require installation of a new placard, which raises questions about part identification after removal. The valve will no longer have its P/N placard; the operator may need to re-identify the valve by other means (e.g., stamping or marking) to satisfy continuing airworthiness requirements, although the AD is silent on this point.

For valves installed after the effective date, the duty is on the person performing the installation to inspect the valve before fitting. This applies to new valves, replacement valves, or modifications. The installer must verify that the placard is not covering the port. This duty applies regardless of whether the valve came from Cessna corrected stock or from spares.

The AD also creates an implicit duty to maintain accurate records. The records check option only works if the operator’s maintenance documentation accurately records part replacements since November 2007. If records are missing or incomplete, the operator has no choice but to perform a physical inspection, which is more costly and time-consuming. This provides an incentive for operators to keep meticulous records, but it also penalises those with poor record-keeping.

Operators have no right to defer compliance; the directive is mandatory with immediate effect. The AD does not provide for alternative methods of compliance (AMOC) or extensions, though such requests could be made to CASA separately. The background states that CASA varied the FAA requirements to allow the records check, which was a departure from the original FAA AD. This suggests CASA was responsive to compliance burden, but the variation is already incorporated into the AD.

The source does not list specific penalties, but Australian airworthiness directives are issued under the Civil Aviation Act 1988 and the Civil Aviation Safety Regulations 1998 (CASR). Breach of an airworthiness directive is a serious regulatory offence. Under CASR, operating an aircraft that does not comply with an applicable airworthiness directive can attract civil penalties, infringement notices, or criminal prosecution depending on the circumstances. For individuals, penalties may include fines of up to several thousand dollars per offence plus demerit points that can lead to licence suspension. For operators or companies, penalties can be significantly higher, and CASA can ground the aircraft, suspend its certificate of airworthiness, or issue a show cause notice.

Enforcement is not detailed in the AD itself, but the practical consequence is clear: a Cessna 207 that has not complied with the requirements is not airworthy and must not be flown. Any flight in non-compliance exposes the pilot and operator to enforcement action. CASA can conduct ramp checks, audit maintenance records, and investigate incidents. The AD is also likely to be cross-referenced in the aircraft’s maintenance schedule, so failure to record compliance will be flagged during annual inspections or when selling the aircraft.

The AD’s immediate "before further flight" compliance leaves no grace period. Operators who are unaware of the AD or who delay compliance face immediate enforcement risk. The effective date of 13 May 2008 means that any flight after that date without the required inspection or records check is technically a violation. Given that the AD was issued on 6 May 2008, operators had only seven days to become aware and act. This short window increases the risk of inadvertent non-compliance, particularly for aircraft that are not hangared or that are in remote locations where information dissemination is slower.

The AD also has extraterritorial reach: Australian-registered aircraft operating overseas must still comply. If a Cessna 207 flies outside Australia after 13 May 2008 without compliance, it may also be subject to enforcement by foreign aviation authorities, which could detain the aircraft.

A notable enforcement feature is that the records check may be performed by a person holding only a private pilot’s licence, but that person does not have authority to certify maintenance. The AD does not require a certification release for the records check; it simply states the determination may be accomplished and certified for by the aeroplane operator holding that licence. The term "certified for" is ambiguous: it likely means the operator must sign or state in the records that the check was done. If a pilot falsely certifies a records check that was not actually performed, they could face action for falsification of records, which carries severe penalties including licence revocation.

This AD interacts with several layers of Australian aviation law. First, it is a standalone instrument made under the Civil Aviation Act 1988, but its practical effect is integrated into the continuing airworthiness regulatory framework. The AD forms part of the aircraft’s type design and must be complied with under CASR Part 42A (for small aeroplanes) or CAO 100.66, depending on the aircraft’s operation. It also interacts with regulations requiring maintenance to be performed in accordance with approved data: the AD provides mandatory instructions.

The AD adopts FAA AD 2008-10-02 with variations, reflecting the bilateral agreement between Australia and the United States on airworthiness approvals. This means that compliance with the FAA AD (as varied) is deemed acceptable by CASA. However, operators who have already complied with the FAA AD may need to check whether the CASA variation requires something different. The source states: "CASA has varied the inspection requirements to allow the aeroplane operator to determine if a P/N 2013142-18 selector valve has been installed since 19 November 2007." So the FAA AD might not have that option; operators should ensure they comply with the Australian version specifically.

The AD interacts with regulations governing maintenance record keeping. Civil Aviation Regulation 42 (and its successors) require detailed records of component changes. The records check under Requirement 1.b relies on those records being accurate. If an operator’s records are incomplete or destroyed, they cannot rely on the records check and must perform a physical inspection. This linkage creates a secondary compliance driver: the value of accurate records.

The AD also interacts with Civil Aviation Safety Regulation 21 on type certification. The defective placard installation could be considered a design or production defect, potentially engaging provisions on manufacturer responsibility, though the AD does not address that. Instead, it places the onus on operators.

Additionally, the AD may interact with aircraft insurance policies. Non-compliance with an airworthiness directive could void coverage or be treated as a breach of warranty. If an operator flies an aircraft without completing this AD and an incident occurs, the insurer may deny cover. This is a significant financial risk beyond the regulatory penalties.

For operators in commercial air transport operations (e.g., charter), the AD interacts with their approved maintenance schedule and operations manual. They must document compliance in the technical log or maintenance record system. The immediate "before further flight" compliance means the operator must halt operations until compliance is confirmed, which may trigger contractual obligations to passengers or cargo consignors.

The AD itself is AD/CESSNA 207/39, which is the 39th airworthiness directive issued for the Cessna 207 series by CASA (or its predecessor AOD, given the numbering system). The immediate source is FAA AD 2008-10-02, Amendment 39-15508, which became effective in the United States on 12 May 2008. CASA’s AD states: "Note 3: FAA AD 2008-10-02 Amdt 39-15508, which becomes effective on 12 May 2008, refers." The Australian AD becomes effective on 13 May 2008, one day later, possibly to align time zones or give a brief window.

CASA made a deliberate variation: the FAA AD likely required physical inspection for all affected aircraft, whereas CASA added the option to check maintenance records first. The source explicitly states: "CASA has varied the inspection requirements to allow the aeroplane operator to determine if a P/N 2013142-18 selector valve has been installed since 19 November 2007." This is a pro-operator variation that reduces compliance burden for those with good records.

There is no mention of superseding any prior AD for the Cessna 207. Since the AD addresses a quality control issue specific to valves manufactured in a limited period (Nov 2007 to Feb 2008), it is likely a new, standalone directive rather than an amendment to an earlier directive. The AD number AD/CESSNA 207/39 suggests that there are at least 38 previous directives for this aircraft model, but this one does not reference them.

The effective date of 13 May 2008 is the date from which compliance is mandatory. The AD was signed on 6 May 2008, allowing only one week for the aviation community to become aware and comply. This short lead time is common for safety-critical ADs but imposes practical difficulties for operators who do not subscribe to daily CASA updates. The distribution of the AD through CASA’s electronic bulletin or the Airworthiness Directive Register is essential for awareness.

There is no mention of a future review or expiry date. Airworthiness directives remain in effect indefinitely or until superseded by a later AD for the same subject. Since the defective valves were only produced for a three-month window, the practical effect of the AD will diminish over time as those valves are identified and corrected. However, the AD stays on the books and applies to any aircraft that later has a P/N 2013142-18 valve installed without prior inspection.

The AD source itself does not reference any litigation. Airworthiness directives are rarely litigated because they are mandatory and generally accepted as necessary for safety. However, there could be background legal activity in the United States relating to the defect. The source mentions that the problem was discovered during a quality control check at Cessna. If any aircraft accidents occurred due to blocked static ports with placard-covered valves, there may be tort claims, but no such accidents are mentioned in the AD.

In Australia, it is extremely unusual for an owner or operator to sue in relation to an AD itself, as the AD is a regulatory instrument. Challenges to ADs have occurred but generally on procedural grounds (e.g., failure to consult, ultra vires). Given the narrow scope of this AD, litigation is unlikely. The compliance costs are low for most operators (a simple inspection), so the incentive to challenge is minimal.

That said, if an operator were to suffer a loss due to grounding or inability to fly while complying, they might seek compensation from Cessna for the defective part. That would be a private commercial dispute, not a challenge to the AD. The AD does not create a private right of action; it merely sets the regulatory requirement.

The AD references FAA AD 2008-10-02. In the United States, there is no publicly known litigation arising from that specific AD. The defect was caught during quality control, not through an accident. This reduces the likelihood of legal action.

One potential litigation angle: if an operator flew after the effective date without compliance and an incident occurred, the operator could face civil or criminal liability. The AD would be used as evidence of the standard of care. A plaintiff could argue that the operator’s failure to comply with the AD constituted negligence per se. That is not litigation against the AD itself but using the AD in a dispute.

For this deep dive, it is sufficient to note that there appears to be no reported case law or tribunal decisions citing AD/CESSNA 207/39. The AD is a standard compliance directive with no contested history. The absence of litigation suggests the inspection requirement was straightforward and widely accepted.

The most significant "gotcha" is the immediate compliance requirement: "before further flight after the effective date". An operator who misses the 13 May 2008 effective date and flies without performing the records check or inspection is in breach. There is no phase-in period or grace. Given that the AD was issued on 6 May, operators had only one week to learn of it and act. Aircraft in storage, undergoing maintenance, or located at remote strips could easily miss the notification.

Another trap is the ambiguity about the records check. The AD states that the operator may "determine if the alternate static air source selector valve has been replaced since 19 November 2007 with P/N 2013142-18, if the valve has not been replaced no further action is necessary." This seems straightforward, but the key question is: what if the valve was replaced before 19 November 2007? The AD only cares about installations after that date. If the valve was replaced in October 2007, no further action. But many operators may misunderstand and think they need to prove the valve is not P/N 2013142-18 regardless of date. The AD is clear: the cut-off is 19 November 2007.

A third gotcha: the placard removal is irreversible. Once removed and discarded, the valve no longer has its P/N identification placard. The AD does not require installation of a new placard. Under other airworthiness requirements, a component must be properly identified with a part number. An operator who removes the placard may need to mark the valve body with the P/N by an alternative method (e.g., engraving, adhesive label) to comply with identification rules in CASR Part 21 or the manufacturer’s instructions. The AD does not address this, potentially creating a secondary non-compliance.

A fourth issue: the physical inspection requires adjusting seats as far aft as possible. In aircraft with seat tracks, this may reduce access to controls or cause seat jams. The AD does not provide caution about re-securing seats for flight after inspection. An operator who fails to secure seats properly after the inspection could create a different hazard.

A fifth gotcha: the AD applies to "aeroplanes that have an alternate static air source selector valve, part number (P/N) 2013142-18, installed after 19 November 2007." This implies that if the valve was installed before that date (even if it is P/N 2013142-18), the AD does not apply. But that is unlikely because the defective valves were only manufactured after 20 November 2007. However, an operator who installed a later-manufactured valve before 19 November 2007 would have a conflict. The AD’s wording seems to rely on installation date, not manufacture date. So if a valve manufactured in December 2007 was installed in February 2008, it is covered. If the same valve was installed in November 2006 (impossible, since it didn’t exist), but the principle is clear: both date and part number matter.

A sixth gotcha: the requirement for Requirement 5 (pre-installation inspection for valves installed on or after the effective date). This means that even if an operator buys a new valve from Cessna after the effective date, which Cessna says has been corrected, the operator must still inspect it before installation. The AD does not allow reliance on Cessna’s statement. This could catch out operators who assume "certified corrected" parts are okay.

Finally, the note that the records check may be performed by a person with a private pilot’s licence. However, if that person makes an incorrect determination (e.g., says the valve hasn’t been replaced when it actually has), the aircraft may be flown in non-compliance. The pilot-operator bears the risk of their own error. There is no protection for good faith mistakes.

Step 1: Determine if your Cessna 207 (any serial number) has an alternate static air source selector valve P/N 2013142-18 installed after 19 November 2007. The simplest way is to review the aircraft’s maintenance records from that date forward. Look for any logbook entries recording installation or replacement of the alternate static air source selector valve. If the part number is listed as 2013142-18, proceed to Step 2. If the records show that only earlier part numbers (2013142-9, -13, -17) were installed, or that the valve has never been replaced since manufacture, you can stop. Record your determination in the aircraft records, signed and dated by a person holding at least a private pilot’s licence.

Step 2: If the records indicate installation of P/N 2013142-18, or if records are incomplete and you cannot determine the part number, you must physically inspect the valve. This inspection should be performed by a qualified person, ideally a licensed aircraft maintenance engineer. Follow Requirement 3 exactly: adjust both pilot and copilot seats as far aft as possible. Using a flashlight and mirror, inspect the forward end of the valve to confirm that the port is clearly visible and not covered by the part number identification placard. If the port is visible and unobstructed, note this in the records and the AD is complied with.

Step 3: If the placard is covering the port, you must remove the placard from the valve body, discard it, and then verify that the port is open and unobstructed. No further rectification is specified. However, consider that removing the placard removes the part number identification. To avoid violating other identification requirements, apply a permanent marking of the part number on the valve body using an approved method (e.g., engraving, indelible ink). Document the placard removal and the new identification method in the records.

Step 4: For any new P/N 2013142-18 valve that you intend to install on or after 13 May 2008, inspect the valve before installation using the same flashlight-and-mirror method to ensure the placard does not obstruct the port. If it does, follow the placard removal procedure. If it does not, proceed with installation. Record the pre-installation inspection in the maintenance records.

Step 5: Ensure compliance is documented before the next flight after the effective date. For aircraft that are in maintenance or storage, the compliance date is still the first flight after 13 May 2008. For new installations, compliance is required at the time of installation.

Step 6: If you are an operator holding the affected part as a spare (not yet installed), inspect the spare part before it is installed. Even if the part came from Cessna after the stock correction, the AD requires the inspection. Do not rely solely on supplier assurances.

Step 7: Consider the practicalities: the inspection may require the removal of cockpit floor panels or seats if the valve is not easily accessible. The AD’s procedure assumes the seats can be moved fully aft; if that is not possible, you may need to remove the seats temporarily. In that case, consult the aircraft maintenance manual for proper removal and reinstallation.

Step 8: Keep a copy of this AD with the aircraft records. The AD number AD/CESSNA 207/39 should be referenced in the maintenance log as a mandatory compliance item. Mark the effective date and the date of your compliance action.

Step 9: If you are a commercial operator, brief your flight crew about the AD and the records they may need to check before dispatch. Ensure that dispatch procedures verify compliance before each flight until the inspection is complete.

Step 10: Monitor CASA’s website for any further amendments, alternative methods of compliance, or corrections to this AD. The AD as issued on 6 May 2008 is the operative version.