Cessna 206 Series Aeroplanes
AD/CESSNA 206/46
Amdt 1
Seat Adjustment Mechanism 9/88
Applicability: Model
206, U206, U206A, U206B, U206C, U206D, U206E, U206F, U206G, TU206A, TU206B, TU206C, TU206D, TU206E, TU206F, TU206G
P206, P206A, P206B, P206C, P206D TP206A, TP206B, TP206C, TP206D
P206E, TP206E
Requirement: Part 1:
Serial Number All
P206-0001 to P206-0603 P20600604 to P20600647.
- Measure each hole in the seat track(s) for excessive wear. If the wear dimension across any hole exceeds 10.67mm (0.42") to a maximum depth of 3.81mm (0.15"), replace the seat track prior to further flight.
Figure 1. Section of Seat Track Showing Hole Wear
b. Visually inspect the seat rail holes for dirt and any debris which may preclude engagement of the seat pin(s). Remove any such material prior to further flight.
c. Lift up on the forward edge of each seat to eliminate all vertical play. With the seat in this position, measure the depth of engagement of each seat pin. If the engagement of any pin is less than 3.81mm (0.15") (see Figure 2), replace or repair necessary components to achieve a seat pin engagement of 3.81mm (0.15") or greater prior to further flight.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Figure 2.
d. Visually inspect seat rollers for flat spots. Ensure all rollers and washers turn freely on their axle bolts (or bushings if installed) and move freely on the seat rails. Replace rollers having flat spots and any worn washers prior to further flight. If there is any binding between the bores of the rollers, washers, and axle bolts (or bushings if installed), remove, clean, and reinstall these parts prior to further flight.
Note: Do not lubricate rollers, washers, axle bolts or bushings as the lubrication will attract dust and other particles which can cause binding.
e. Measure the wall thickness of the roller housing and the tang (see Figure 2). If the tang thickness has worn to less than 1/2 the housing thickness, replace the roller housing prior to further flight.
f. Check the spring(s) that keep the lock pin(s) in position in the track holes for positive engagement action. Replace any spring which does not provide positive engagement prior to further flight.
g. Visually inspect the seat tracks for cracks in accordance with Cessna SIL SE83- 6, dated 11 March 1983. Any limitation imposed as a result of seat track cracking shall be endorsed on the Maintenance Release. Replace any seat rail exceeding the crack criteria as specified in SE83-6 with a serviceable rail prior to further flight.
Part 2:
In accordance with temporary schemes approved by the Secretary, modify seat adjustment mechanisms to permanently limit seat travel to 255mm (10") or to 153mm (6") as applicable, aft of the forward stop.
Note: FAA AD 87-20-03 R1 refers.
Compliance: i. For aircraft with less than 1000 hours time in service as at 28 January 1988, prior to attaining 1100 hours time in service; or
ii. For aircraft with more than 1000 hours time in service as at 28 January 1988, at the next inspection for Maintenance Release issue after 28 January 1988; and
iii. Thereafter at each inspection for Maintenance Release issue. B. Pending any component replacement necessary to fully comply with Requirement: Part 1, compliance with Requirement: Part 2 is an acceptable alternative until 30 June 1989.
Background: There has been a history of seat adjustment mechanism failure that has resulted in accidents. As there will probably be a high demand for replacement items, Part 2 of the Requirement enables continued flight. Schemes acceptable to the Secretary are available from Regional Offices.
Overview
The Civil Aviation (Airworthiness) Regulations 1998, enacted by the Commonwealth of Australia, were introduced to ensure the safety and airworthiness of aircraft within Australian airspace. This legislation established a comprehensive regulatory framework to address safety issues and compliance standards for aircraft operation. One such regulation, F2006B05251, specifically targets seat adjustment mechanisms in Cessna 206 series aeroplanes to mitigate the risk of accidents caused by seat adjustment failures. The regulation was introduced by the Civil Aviation Safety Authority (CASA) under the authority of the Secretary, aiming to improve safety by mandating inspections and modifications to seat adjustment mechanisms. Compliance with these directives is essential to ensure that the seat adjustment mechanisms do not compromise the structural integrity or operational safety of the aircraft.
Scope and Application
This legislative instrument applies to the specified models of Cessna 206 series aeroplanes, identified by their serial numbers and model series (e.g., P206, U206, etc.), which are subject to airworthiness directives issued by the Civil Aviation Safety Authority. The legislation mandates specific maintenance checks and repairs to the seat adjustment mechanisms of these aircraft to ensure safety and compliance with civil aviation standards. The requirement to inspect and potentially replace seat tracks, pins, rollers, and other components is stringent, with clear measurements and visual inspection criteria provided to aid in compliance. The geographic reach of this directive is national, as it applies to aircraft registered and operated within Australia. The Act does not specify exclusions or exemptions, and compliance is mandatory for all aircraft within the specified range. Furthermore, the application of this legislation extends through subordinate instruments, which may provide additional details or modifications to the directives as necessary. Compliance must be achieved at specific intervals based on the aircraft's service hours, with a phased approach to allow for the potential shortage of replacement parts.
Key Provisions
The main sections of this legislation focus on the inspection and modification of seat adjustment mechanisms in specific Cessna 206 Series Aeroplanes. Section 1 details the serial numbers and model types applicable to the directive (Part 1). This section mandates that certain measurements and inspections be conducted on the seat tracks, seat rails, seat rollers, washers, axle bolts, bushings, spring mechanisms, and tang thickness to ensure airworthiness. The directive also requires the elimination of vertical play in the seats, checking for cracks in the seat tracks, and ensuring all components are free from debris and properly engaged. Section 2 of the legislation requires the modification of seat adjustment mechanisms to permanently limit seat travel to either 255mm (10 inches) or 153mm (6 inches) aft of the forward stop. Compliance with these requirements is contingent on the aircraft's time in service and must be met at specific intervals.
The obligations imposed by this Act include detailed inspections and necessary modifications to the seat adjustment mechanisms to ensure safety and airworthiness. Operators must measure the wear on seat track holes, ensure seat rails and rollers are free from debris, eliminate vertical play, check for flat spots on rollers, measure wall thicknesses, and inspect spring mechanisms. Furthermore, operators must comply with the modification requirements outlined in Part 2 of the directive based on the aircraft's time in service. These obligations must be met at specified times and intervals to maintain compliance with the legislation.
Failure to comply with the requirements set forth in this legislation can lead to serious consequences. The legislation does not explicitly state the penalties for non-compliance, but non-compliance can result in the aircraft being deemed unairworthy, which can lead to significant operational disruptions and potential grounding of the aircraft. Additionally, failure to adhere to these safety directives can result in regulatory actions by the Civil Aviation Safety Authority, including fines, enforcement actions, and potential criminal charges if the non-compliance leads to an accident or incident. The exact penalties and consequences would depend on the severity of the non-compliance and its impact on aviation safety.