# AIR760-2008-03-S-5700-ACS: Aluminum Spar Caps

- Type: Airworthiness concern sheet: the FAA asks for information before deciding whether an AD is needed
- Status: Current
- Issued: February 27, 2008
- Systems (JASC): [5700 - Wing Structure](https://openairdocs.org/jasc/5700)
- Product type: Aircraft, Small Airplane
- Products: Air Tractor AT-300 and AT-400
- Data sheets: [TCDS A9SW](https://openairdocs.org/tcds/A9SW), [TCDS A17SW](https://openairdocs.org/tcds/A17SW)
- ADs it names: [AD 2008-09-10](https://openairdocs.org/ad/2008-09-10)
- PDF: https://openairdocs.org/files/sha256/26/6b/266b56098d4aeb9a0d7aae62fcea18a7663d2970a8adb812c745a45818eb626d
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/FAA00000000000ACS_760200803S5700.0001
- DRS record last changed: December 19, 2025
- Page: https://openairdocs.org/acs/AIR760-2008-03-S-5700-ACS

## Text

This is OCR from the scanned FAA concern sheet. OCR can misread letters and numbers.

Airworthiness FAA Concern Sheet Date:2/27/08 Full Name: Robert A. Romero Title: Aerospace Engineer Organization: ASW-150 Department:

Address: 2601 Meacham Blvd City: Fort Worth State: TX Zip: 76133 Telephone/Fax Number: 817-222-5102/5960 E-Mail: Robert.A.Romero@faa.gov Make, Model, Series, Serial No.:

AT-300 and AT-400 Series airplanes with aluminum spar caps Reason for Airworthiness Concern:

Revise current AD to add requirement to repetitively inspect prior to modification/replacement.

FAA Description of Airworthiness Concern (Who, What, Where, When, How? Attachments: RA and appropriate data) and 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 FAA intends to revise AD 2003-06-01- to add repetitive inspection requirements for the AT-300/AT-400 Series airplanes with aluminum spar caps. Based on a recent report of an AT-301 that had cracks discovered at hours below the modification time listed in AD 2003-06-01, the FAA has re-evaluated its fatigue management plan for the AT-300/400 series airplanes with aluminum spar caps. All airplanes with aluminum spar caps, except those with part number 20990-2 installed, will be required to repetitively inspect their lower spar caps beginning at 3,500 hours TIS.

Risk Assessment

a. Safety Effect: 4

b. Operational Use: 1 Safety Risk Factor = a x b x c + d + e + f + g

c. Percentage use by Population: 1 = 4x1x1+3+2+2-2

d. Number of Occurrences: 3 = 9

e. Events vs. Population: 2

f. Time between Events: 2 Urgent Safety of Flight AD

g. Aircraft Type: -2 Potential Immediate Adopted AD Attachments: *SDR(s) • *A/IDSL *SL(s) • *SAIBO *FAASR/NTSBSR • *ADD *AOCU *RAL Notification: FAA • *AOPA *EAA - Type Club *TC Holder Other: NAAA Response Requested 12/20/04: Emergency (10 days) Alert (30 days) Information (90 days) L (Word 97 Version: Manually Check Appropriate 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 (BAA); Type Certificate (TC)

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