# AD 87-12-05: Gas Producer Turbine and Power Turbine Disks - Type: Airworthiness directive - Status: Historical - Products: Honeywell International T5313B - Effective: July 20, 1987 - Superseded by: [AD 2006-01-05](https://openairdocs.org/ad/2006-01-05) - Product type: Engine - Amendment: 39-5640 - Registered aircraft: 108 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/51E5B4CFA6F3C85686256842006D9CB6.0001 - DRS record last changed: August 7, 2025 - Page: https://openairdocs.org/ad/87-12-05 ## The airworthiness directive 87-12-05 AVCO LYCOMING: Amendment 39-5640. Applies to Avco Lycoming T5313B turboshaft engines. Compliance is required as indicated, unless already accomplished. To prevent an uncontained engine failure, remove gas producer turbine (GPT) and power turbine (PT) disks and spacers from service, and replace with serviceable parts, in accordance with the following schedules: (a) GPT disk, Part Number (P/N) 1-100-133-01: (1) Within the next 250 hours in service (HIS) or 100 cycles in service (CIS) after the effective date of this AD, whichever occurs first, for those disks that have accumulated a total service life in excess of 24,750 HIS or 9,900 CIS since new on the effective date of this AD. (2) Prior to accumulating 25,000 HIS or 10,000 CIS since new, whichever occurs first, for those disks that have accumulated a total service life equal to or less than 24,750 HIS or 9,900 CIS since new on the effective date of this AD. (b) PT disk, P/N 1-140-272-01: (1) Withinthe next 100 HIS or 50 CIS after the effective date of this AD, whichever occurs first, for those disks that have accumulated a total service life in excess of 9,000 HIS or 4,550 CIS since new on the effective date of this AD. (2) Prior to accumulating 9,100 HIS or 4,600 CIS since new, whichever occurs first, for those disks that have accumulated a total service life equal to or less than 9,000 HIS or 4,550 CIS since new on the effective date of this AD. (c) GPT spacer, P/N 1-100-294-03: (1) Within the next 250 HIS or CIS, after the effective date of this AD, whichever occurs first, for those spacers that have accumulated a total service life in excess of 24,750 HIS or CIS since new on the effective date of this AD. (2) Within the next 12,500 HIS or CIS, after the effective date of this AD, whichever occurs first, for those spacers on which the total service life is not known on the effective date of this AD. (3) Prior to accumulating 25,000 HIS or CIS since new, whichever occurs first, for those spacers that have accumulated a total service life equal to or less than 24,750 HIS or CIS since new on the effective date of this AD. (d) PT spacer, P/N 1-140-169-03: (1) Within the next 250 HIS or 100 CIS, after the effective date of this AD, whichever occurs first, for those spacers that have accumulated a total service life in excess of 24,750 HIS or 9,900 CIS since new on the effective date of this AD. (2) At the next PT second stage disk removal, after the effective date of this AD, for those spacers on which the service life is not known on the effective date of this AD. (3) Prior to accumulating 25,000 HIS or 10,000 CIS since new, whichever occurs first, for those spacers that have accumulated a total service life equal to or less than 24,750 HIS or 9,900 CIS since new on the effective date of this AD. (e) PT spacer, P/N 1-140-169-04: (1) Within the next 250 HIS or CIS after the effective date of this AD, whichever occurs first, for those spacers that have accumulated a total service life in excess of 24,750 HIS or CIS since new on the effective date of this AD. (2) Within the next 12,500 HIS or CIS after the effective date of this AD, whichever occurs first, for those spacers on which the total service life is not known on the effective date of this AD. (3) Prior to accumulating 25,000 HIS or CIS since new, whichever occurs first, for those spacers that have accumulated a total service life equal to or less than 24,750 HIS or CIS since new on the effective date of this AD. NOTE: Avco Lycoming Service Bulletin Number 0020, Revision 2, dated January 3, 1986, reflects the new lives specified in this AD, and provides instruction for computing and recording part life. Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD may be accomplished. Upon request, an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Engine Certification Office, Aircraft Certification Division, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803. Upon submission of substantiating data by an owner or operator through an FAA maintenance inspector, the Manager, Engine Certification Office, New England Region, may adjust the compliance times specified in this AD. This amendment becomes effective on July 20, 1987. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS E17EA](https://openairdocs.org/tcds/E17EA): Ozark Aeroworks LLC; names 1 of 6 models: T5313B ## 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: 108 (0 by airframe model, 108 by engine model) - Makers: Bell 76, Garlick Helicopters 8, Grumman 4, Southwest Florida 3, Western International Avia 2, Williams Helicopter 2, Anderson Douglas 1, Bell Helicopter 1, Bell-Colonial 1, Bell-Sw Florida Avn 1 Models with the most aircraft: - [Lycoming T-53 series](https://openairdocs.org/engine/lycoming-t-53-series): 95 aircraft (engine model) - [Lycoming T5313B](https://openairdocs.org/engine/lycoming-t5313b): 8 aircraft (engine model) - [Honeywell T5313B](https://openairdocs.org/engine/honeywell-t5313b): 5 aircraft (engine model) All 5 models: https://openairdocs.org/ad/87-12-05/models.md Every aircraft: https://openairdocs.org/ad/87-12-05/aircraft.md ## Related documents - [AD 2006-01-05](https://openairdocs.org/ad/2006-01-05): Turboshaft engine ยท Honeywell International T53-L-703, T53-L-13B/D, T53-L-13B S/SB and 12 more. Effective Feb 16, 2006. Supersedes this AD 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.