AIR770-2009-08-S-5700-ACS

Airworthiness FAA Concern Sheet Date: August 14, 2009 Full Name: Roger Caldwell Title: Aerospace Engineer Organization: Denver Aircraft Cert. Office Department: ANM-100D Address : 26805 East 68"h Ave., Room 214 City: Denver State: CO ZIP: 80249 Telephone Number: 303-342-1086 E-mail roger.caldwell(@)faa.gov FAA Description of Airworthiness Concern :

Make, Model, Series, Serial No.: Ercoupe 415C, 415CD, 415D, 415E, 415G, Forney F1 and FIA, Alon A-2 and A-2A, and Mooney M10 aircraft.

Reason for Airworthiness Concern: The in-flight breakup of an Ercoupe Model 415D resulting in two fatalities.

On December 13, 2008, an Ercoupe model 415D aircraft crashed after a complete in-flight breakup resulting in (2) fatalities.

The aircraft was being operated at other than cruise flight and was maneuvering. The inspection of the wreckage revealed that improper maintenance was performed on the wing spar. Specifically, holes had been drilled into wing spar to facilitate remounting of a seat pan and other unauthorized components. The drill holes were in the exact location where the wings separated from the aircraft during the in-flight break up. It was concluded from metallurgy analysis that both wings separated at the points of unauthorized maintenance actions and the drill holes significantly contributed to the overall weakness of the wing spar. Three (3) aircraft of the same type design were recently inspected by the FAA for maintenance abnormalities to wing spars. One of the three aircraft had the same modification to the seat pan as the accident aircraft.

At this time, the FAA has not made a final determination on what type of corrective action should be taken. There is a FAA safety recommendation 09.087 to revise the AD 2003-21-01, requiring a complete wing spar inspection for corrosion, damage, and any unauthorized maintenance actions performed on the wings of all Univair Aircraft Models. The FAA's final determination will depend in part on the information received in response to this Airworthiness Concern Sheet (ACS).

Request for Information (Proposed Alternate Inspection/Repair Procedures, Cost Impact, Etc.)

Note: Any comments or replies to the FAA need to be as specific as possible. Please provide specific examples to illustrate your comments/concerns) :

The ACS is intended as a means for Federal Aviation Administration (FAA) Aviation Safety Engineers to coordinate airworthiness (A/W) concerns with aircraft through Associations and Type Clubs. Please forward any comments you have to Roger Caldwell via e-mail using the address above.

The FAA encourages comments on this topic, including, but not limited to the following areas:

Technical comments on improper maintenance and unauthorized alterations performed on the wing spar as noted above for FAA safety recommendation 09.087.

Are the correct models identified in this ACS (Airworthiness Concern Sheet)?

Are there alternate methods to address this situation?

Have you ever discovered improper or unauthorized maintenance actions or damage as described in this ACS, to be present on any area of the wing spar?

Have you ever discovered other related damage or corrosion on the wing spar, not described in this ACS? If so, what actions did you take to correct the situation?

Response Date Requested: 10/07/09

Attachments: *SDR(s) *A/IDS *SL(s)L | *SAIB| | *FAASR/*NTSBSRL _ *AD_ *AMOC| *RAL Notification: FAA _ *AOPA *EAA Type Club *TC Holder Other:

Response Requested 10/07/09: Emergency (10 days) Alert (30 days) Information (90 days) (Space Bar Adds "X" to Check Boxes) *Service Difficulty Reports (SDRS); Accident/Incident Data System (A/IDS); Service Letter (SL); Special Airworthiness Information Bulletin (SAIB);

Federal Aviation Administration (FAA)/National Transportation Safety Board (NTSB) Safety Recommendation (FAASR/NTSBSR); Airworthiness Directive (AD); Alternate Method of Compliance (AMOC); Risk Assessment (RA); Aircraft Owners & Pilots Association (AOPA);

Experimental Aircraft Association (EAA); Type Certificate (TC)