# AD 93-02-07: Vertical Fin Spar

- Type: Airworthiness directive
- Status: Current
- Products: Bell Helicopter Textron 412
- Effective: March 22, 1993
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-8489
- Docket: 92-ASW-39
- Registered aircraft: 11 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C4BD52DE3173393F86256A4D00720DD7.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/93-02-07

## The airworthiness directive

93-02-07 BELL HELICOPTER TEXTRON, INC., (BHTI): Amendment 39-8489. Docket Number 92-ASW-39. Supersedes AD 85-17-03R1, Amendment 39-5194, Docket Number 85- ASW-37.

Applicability: BHTI Model 412 helicopters, serial numbers 33001 through 33120 and serial numbers 34001 through 34012, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the vertical fin spar cap assembly, which could result in loss of the vertical fin and subsequent loss of control of the helicopter, accomplish the following:

  (a) Within 25 hours time in service after the effective date of this AD, inspect the vertical fin spar cap assembly, P/N 212-030-447-001, in accordance with the Accomplishment Instructions, Part I, of BHTI Alert Service Bulletin (ASB) No. 412-92-65, dated August 17, 1992, and every 25 hours time in service thereafter until it is replaced with a vertical fin spar cap assembly, P/N 212-030-447-101, in accordancewith the Accomplishment Instructions, Part II, of the ASB. If any cracks, corrosion or doubler debonding is found, replace the spar cap assembly before further flight with an airworthy part in accordance with the Accomplishment Instructions, Part II, of the ASB.

  (b) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Rotorcraft Certification Office, ASW-170, 4400 Blue Mound Road, Fort Worth, Texas 76106. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Certification Office.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Manager, Rotorcraft Certification Office.

  (c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the helicopterto a location where the requirements of this AD can be accomplished.

  (d) The inspection and replacement of the fin spar cap shall be done in accordance with the Accomplishment Instructions, Parts I and II, of BHTI ASB No. 412-92-65, dated August 17, 1992. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, Texas 76101-0482. Copies may be inspected at the FAA, Office of the Assistant Chief Counsel, 4400 Blue Mound Road, Bldg. 3B, Room 158, Fort Worth, Texas; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

  (e) This amendment becomes effective on March 22, 1993.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H4SW](https://openairdocs.org/tcds/H4SW): Bell Textron Inc.; names 1 of 4 models: 412

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 11 (11 by airframe model, 0 by engine model)
- Makers: Bell 11

Models with the most aircraft:

- [Bell 412](https://openairdocs.org/model/bell-412): 11 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/93-02-07/models.md
Every aircraft: https://openairdocs.org/ad/93-02-07/aircraft.md

Its text cites no advisory circulars or STCs.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.