# AD 73-06-02: Fuel Siphoning - Type: Airworthiness directive - Status: Current - Products: Twin Commander 500, 500-A, 500-B, 500-U, 520, 560, 560-A, 560-E, 560-F, 680, 680-E, 680-F and 4 more - Effective: March 19, 1973 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Small airplane - Amendment: 39-1606 - Registered aircraft: 201 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/63084EFE85EA64BF86256A38005D8862.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/73-06-02 ## The airworthiness directive 73-06-02 AERO COMMANDER: Amdt. 39-1606. Applies to all Models 500, 500A, 500B, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), 680FL, 680FL(P) and 720 series airplanes certificated in all categories. Compliance required within the next 200 hours' time in service after the effective date of this AD, unless already accomplished. To prevent siphoning of fuel from the fuel tanks and thereby contribute to fuel exhaustion with resultant stoppage of both engines, accomplish the following: a. On Models 520 and 560, serial numbers 1 through 230, replace the standard fuel cap assemblies with non-siphoning fuel cap assemblies, Aero Commander Kit No. 87A-1. b. On the following models, replace the standard fuel cap assemblies with non- siphoning fuel cap assemblies, Aero Commander Kit No. 87A-2 (optional fuel caps already installed by use of Aero Commander Kit No. 87 are acceptable): (1) Models 500, 500A, 500B, 500U, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), 680FL(P) and 720, serial numbers 231 through 1854. (2) Model 680FL, serial numbers 1261 through 1738. c. The compliance time for this AD may be adjusted up to a maximum of 50 hours to coincide with the aircraft's annual or 100 hour scheduled inspection. Aero Commander Custom Kit No. 87A contains the hardware and instructions necessary to accomplish this modification. Equivalent replacement parts approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, may be used. This amendment becomes effective March 19, 1973. ## Affected data sheets (2) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS 6A1](https://openairdocs.org/tcds/6A1): Twin Commander Aircraft LLC; names 8 of 9 models: 500, 500A, 500B, 500U, 520, 560, 560A, 560E - [TCDS 2A4](https://openairdocs.org/tcds/2A4): Twin Commander Aircraft LLC; names 6 of 21 models: 680-F, 680-E, 560-F, 720, 680-FL, 680 ## 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: 201 (201 by airframe model, 0 by engine model) - Makers: Aero Commander 201 Models with the most aircraft: - [Aero Commander 500-B](https://openairdocs.org/model/aero-commander-500-b): 85 aircraft (airframe model) - [Aero Commander 500-A](https://openairdocs.org/model/aero-commander-500-a): 23 aircraft (airframe model) - [Aero Commander 500](https://openairdocs.org/model/aero-commander-500): 12 aircraft (airframe model) - [Aero Commander 520](https://openairdocs.org/model/aero-commander-520): 12 aircraft (airframe model) - [Aero Commander 680](https://openairdocs.org/model/aero-commander-680): 12 aircraft (airframe model) - [Aero Commander 680-F](https://openairdocs.org/model/aero-commander-680-f): 11 aircraft (airframe model) - [Aero Commander 560-A](https://openairdocs.org/model/aero-commander-560-a): 10 aircraft (airframe model) - [Aero Commander 680FL](https://openairdocs.org/model/aero-commander-680fl): 10 aircraft (airframe model) - [Aero Commander 560-F](https://openairdocs.org/model/aero-commander-560-f): 6 aircraft (airframe model) - [Aero Commander 560-E](https://openairdocs.org/model/aero-commander-560-e): 5 aircraft (airframe model) - [Aero Commander 680FL P](https://openairdocs.org/model/aero-commander-680fl-p): 5 aircraft (airframe model) - [Aero Commander 680-E](https://openairdocs.org/model/aero-commander-680-e): 4 aircraft (airframe model) - [Aero Commander 500-U](https://openairdocs.org/model/aero-commander-500-u): 3 aircraft (airframe model) - [Aero Commander 560](https://openairdocs.org/model/aero-commander-560): 2 aircraft (airframe model) - [Aero Commander 720](https://openairdocs.org/model/aero-commander-720): 1 aircraft (airframe model) All 15 models: https://openairdocs.org/ad/73-06-02/models.md Every aircraft: https://openairdocs.org/ad/73-06-02/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.