# AD 88-04-07: Wing Spar Nuts Inspection - Type: Airworthiness directive - Status: Current - Products: Textron 100, 65, 65-80, 65-88, 65-90, 65-A80, 65-A80-8800, 65-A90, 65-B80, 70, 99, 99A and 9 more - Effective: April 18, 1988 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Small airplane - Amendment: 39-5892 - Registered aircraft: 627 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/988AB3419AFED65B862569B300529341.0001 - DRS record last changed: January 21, 2026 - Page: https://openairdocs.org/ad/88-04-07 ## The airworthiness directive 88-04-07 BEECH: Amendment 39-5892. Applies to the following Models and serial numbered airplanes, certificated in any category, equipped with Inconel bolts and nuts in the wing lower forward spar attachments, and which have not installed Integral Fitting Spar Kit No. 90-4077-1S or 99-4023-1S or 100-4007-1S. MODELS SERIAL NUMBERS 65, A65, A65-8200 L-1, L-2, L-6, LF-7, LF-8 and LC-1 through LC-335 70 LB-1 through LB-35 65-80, 65-A80, LD-1 through LD-511 65-A80-8800, and 65-B80 65-88 LP-1 through LP-47 65-90, 65-A90, B90, and C90 LJ-1 through LJ-1087 (except LJ-1085) E90 LW-1 through LW-347 99, 99A, A99A, and B99 U-1 through U-164 (except U-50) 100 and A100 B-1 through B-247 B100 BE-2 through BE-137 NOTE: Queen Air Model 65, 70, 80, and 88 airplanes were not factory approved for field installation of Inconel wing attachment hardware, however, some of these airplanes may have had Inconel hardware installed by field approval. Compliance: Required prior to further flight after receipt of this AD unless already accomplished. To prevent possible failure of the wing lower forward spar attachment, accomplish the following: (a) Visually inspect each Inconel nut in the lower forward wing spar attachments in accordance with the instructions in Beech Service Bulletin No. 2248, dated February 1988. If no cracks are found, return the airplane to service. (b) If a crack in any nut is found, prior to further flight replace the nut with a specially marked Part No. 81790-1414 nut per Figure 2 of the above referenced Service Bulletin. (c) This AD does not apply if each affected nut has been replaced by a specially marked Part No. 81790-1414 nut per Figure 2 of the above referenced Service Bulletin. (d) Return cracked nuts to Beech Aircraft Corporation, Commercial Service, Department 52, P.O. Box 85, Wichita, Kansas 67201-0085. (e) Airplanes may be flown in accordance with FAR 21.197 to a location where thisAD can be accomplished. (f) An equivalent method of compliance with this AD, if used, must be approved by the Manager, Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone (316) 946-4400. All persons affected by this directive may obtain copies of the documents referred to herein upon request to Beech Aircraft Corporation, Commercial Service, Department 52, Wichita, Kansas 67201-0085, or these documents may be examined at the FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106. This amendment, 39-5892, becomes effective on April 18, 1988 to all persons except those to whom it has already been made effective by priority letter from the FAA dated February 24, 1988, and is identified as AD 88-04-07. ## Affected data sheets (2) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS 3A20](https://openairdocs.org/tcds/3A20): Textron Aviation Inc.; names 14 of 22 models: B90, 65-A80-8800, 65-B80, 65-A80, 65, A65-8200, E90, 65-88… - [TCDS A14CE](https://openairdocs.org/tcds/A14CE): Textron Aviation Inc.; names 7 of 12 models: A99A, B99, B100, A100, 100, 99A, 99 ## 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: 627 (627 by airframe model, 0 by engine model) - Makers: Beech 624, Monocoupe 1, Raytheon 1, Rockwell International 1 Models with the most aircraft: - [Beech C90](https://openairdocs.org/model/beech-c90): 216 aircraft (airframe model) - [Beech E-90](https://openairdocs.org/model/beech-e-90): 145 aircraft (airframe model) - [Beech B100](https://openairdocs.org/model/beech-b100): 58 aircraft (airframe model) - [Beech 65-A90](https://openairdocs.org/model/beech-65-a90): 34 aircraft (airframe model) - [Beech B90](https://openairdocs.org/model/beech-b90): 29 aircraft (airframe model) - [Beech 99](https://openairdocs.org/model/beech-99): 23 aircraft (airframe model) - [Beech 65](https://openairdocs.org/model/beech-65): 22 aircraft (airframe model) - [Beech 65-B80](https://openairdocs.org/model/beech-65-b80): 15 aircraft (airframe model) - [Beech A100](https://openairdocs.org/model/beech-a100): 15 aircraft (airframe model) - [Beech 100](https://openairdocs.org/model/beech-100): 14 aircraft (airframe model) - [Beech 99A](https://openairdocs.org/model/beech-99a): 11 aircraft (airframe model) - [Beech 65-90](https://openairdocs.org/model/beech-65-90): 7 aircraft (airframe model) - [Beech A65](https://openairdocs.org/model/beech-a65): 6 aircraft (airframe model) - [Beech 65 (LF-23F)](https://openairdocs.org/model/beech-65-lf-23f): 6 aircraft (airframe model) - [Beech B-99](https://openairdocs.org/model/beech-b-99): 6 aircraft (airframe model) - [Beech 70](https://openairdocs.org/model/beech-70): 4 aircraft (airframe model) - [Beech 65-A80](https://openairdocs.org/model/beech-65-a80): 3 aircraft (airframe model) - [Beech 65-88](https://openairdocs.org/model/beech-65-88): 3 aircraft (airframe model) - [Beech 65-A80-8800](https://openairdocs.org/model/beech-65-a80-8800): 3 aircraft (airframe model) - [Beech 65-80](https://openairdocs.org/model/beech-65-80): 2 aircraft (airframe model) All 25 models: https://openairdocs.org/ad/88-04-07/models.md Every aircraft: https://openairdocs.org/ad/88-04-07/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.