FAA Airworthiness Directive on Mooney M20C to M20G
Posted by BAS | Aircraft Salvage Experts on Feb 6th 2023
FAA Issues a new Airworthiness Directive on Elevator Balance Weights for Certain Mooney variants
The FAA has issued a new Airworthiness Directive for specific Mooney aircraft variants effective Feb 13. According to official reports published by the FAA, this Airworthiness Directive was sparked by increased cases of the elevator balance weight cracking and corroding on some Mooney variants. The FAA issued the directive due to the increased risk related to the faulty component.
The AD emphasized that if the corrosion and cracking conditions are not corrected early enough, the result could be a catastrophic failure due to the partial separation of the elevator balance weight in flight. The consequence would be a severe elevator flutter condition and total or partial loss of voluntary control over the aircraft.
In the directive, the FAA instructed new maintenance procedures for the elevator balance weight to prevent the cracks and corrosion from getting to severe levels, improving the safety of the Mooney variants affected. Among the variants on the directive are Models M20C, M20D, M20E, M20F, and M20G, which have smooth skin elevators, part number (P/N) 430000-503, and P/N 430000-504 as well as a hybrid elevator balance.
The FAA dictated in the AD that maintenance personnel should conduct additional investigations to identify corrosion or cracking in the installed elevator balance weights. Afterward, depending on the analysis and diagnosis of the components, the maintenance personnel may exchange each elevator balance weight for an undamaged non-hybrid or lead elevator balance weight.
Public Review and Comments
The FAA also gave further directives to objections or recommendations that the general public may have on the Airworthiness Directive before its effective date on Feb 13. According to the formal publication, the US aviation watchdog will carefully analyze the comments and recommendations from the public, which may change the course of the directive if sufficient information or evidence is provided.
According to Section 553(b)(3)(B) of the Administrative Procedure Act (APA), the authority has the mandate to issue a final rule on a particular matter that expresses high-risk levels and needs to be effective immediately. In this case, the listed Mooney variants possess the risk of elevator balance weight cracking and corrosion that may cause flight control problems. Therefore, the nature of the fault on the variants dictates that the Airworthiness Directive is final and effective on the day it was issued.
The FAA advised that corrosion on the specified elevator section develops quickly over time and is difficult to isolate without close inspection. For this reason, all models M20C, M20D, M20E, M20F, and M20G should have their elevator balance weight inspected before further flight.
Compliance
Like all maintenance operations, inspecting and maintaining the overall good condition of the elevator balance weights will require additional time and costs. The FAA estimates that the airworthiness directive applies to 3,098 aircraft registered in the United States and the initial inspection of P/N 430018-1 will take 1 hour. The elevator balance weight must be replaced before flight. The complete crack and corrosion maintenance is estimated to require 6 hours.
[Federal Register, Volume 88 Number 18 (Friday, January 27, 2023)]
[Rules and Regulations] [Pages 5246-5249]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-01730]