N421SL

01 /  Registration

Filed with the Federal Aviation Administration

Every cell below is a literal field from the FAA Aircraft Registry. Click any value to open the FAA registry record for N421SL.

02 /  NTSB Records

Events on file with the National Transportation Safety Board

03 /  Airworthiness Directives

Applicable to SCHLEICHER ASK-21

Federal Aviation Administration airworthiness directives matched to make and model. Each entry links to the Federal Register publication.

• Dec 14, 2017

  Airworthiness Directives; Alexander Schleicher GmbH & Co. Segelflugzeugbau Gliders

  We are adopting a new airworthiness directive (AD) for all Alexander Schleicher GmbH & Co. Segelflugzeugbau Models ASH 25M and ASH 26E gliders. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes th…

  Federal Register →

• Sep 22, 2017

  Airworthiness Directives; Alexander Schleicher GmbH & Co. Segelflugzeugbau Gliders

  We propose to adopt a new airworthiness directive (AD) for all Alexander Schleicher GmbH & Co. Segelflugzeugbau Models ASH 25M and ASH 26E gliders. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The…

  Federal Register →

• Feb 10, 2017

  Airworthiness Directives; Alexander Schleicher GmbH & Co. Gliders

  We are adopting a new airworthiness directive (AD) for Alexander Schleicher GmbH & Co. Model ASK 21 gliders. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as cable slack i…

  Federal Register →

• Nov 10, 2016

  Airworthiness Directives; Alexander Schleicher GmbH & Co. Gliders

  We propose to adopt a new airworthiness directive (AD) for Alexander Schleicher GmbH & Co. Model ASK 21 gliders. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition…

  Federal Register →

• Apr 3, 2014

  Airworthiness Directives; Alexander Schleicher, Segelflugzeugbau Gliders

  We are adopting a new airworthiness directive (AD) for all Alexander Schleicher, Segelflugzeugbau Model ASK 21 gliders. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as in…

  Federal Register →

• Jan 15, 2014

  Airworthiness Directives; Alexander Schleicher, Segelflugzeugbau Gliders

  We propose to adopt a new airworthiness directive (AD) for Alexander Schleicher, Segelflugzeugbau Model ASK 21 gliders. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe co…

  Federal Register →

• Jun 21, 1999

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK 21 Gliders

  This action confirms the effective date of Airworthiness Directive (AD) 95-11-15 R1, which applies to Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK 21 gliders. AD 95-11- 15 R1 requires replacing the parallel rocker with a part of improved design and incorporating flight manual revisions, but only for those gliders with the automatic…

  Federal Register →

• Apr 26, 1999

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK 21 Gliders

  This amendment revises Airworthiness Directive (AD) 95-11-15, which currently requires replacing the parallel rocker with a part of improved design and incorporating flight manual revisions on all Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK 21 gliders. AD 95-11-15 was the result of two incidents of the parallel rocker breaking at…

  Federal Register →

• Jun 4, 1998

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Models ASW-19 and ASK 21 Sailplanes

  This amendment adopts a new airworthiness directive (AD) that applies to certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Models ASW-19 and ASK 21 sailplanes. This AD requires: modifying the rudder surface panels; replacing the airbrake bellcrank; and modifying the rear canopy hinge structure. This AD is the result of mandatory continuin…

  Federal Register →

• May 13, 1998

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK 21 Sailplanes

  This amendment adopts a new airworthiness directive (AD) that applies to all Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK 21 sailplanes that have certain modifications installed. This AD requires changing the sailplane flight manual's weight and balance information. This AD is the result of mandatory continuing airworthiness inform…

  Federal Register →

• Apr 28, 1998

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK 21 Sailplanes

  This amendment adopts a new airworthiness directive (AD) that applies to certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK 21 sailplanes. This AD requires inspecting the S- shaped rudder pedal tube for displacement, and correcting any displacement of the plastic tube. This AD is the result of mandatory continuing airworthiness i…

  Federal Register →

• Apr 20, 1998

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK 21 Sailplanes

  This amendment adopts a new airworthiness directive (AD) that applies to certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK 21 sailplanes. This AD requires removing certain pages from the sailplane flight manual and replacing these pages with new pages having different information regarding spin and stall recovery. This action is…

  Federal Register →

• Mar 20, 1998

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK-21 Sailplanes

  This amendment adopts a new airworthiness directive (AD) that applies to certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK-21 sailplanes. This AD requires replacing any tow release cable assembly that does not have a swivel-type end with a cable assembly that does have a swivel-type end. This AD is the result of mandatory contin…

  Federal Register →

• Mar 20, 1998

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK-21 Sailplanes

  This amendment adopts a new airworthiness directive (AD) that applies to Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK-21 sailplanes that do not have a certain automatic elevator connection installed. This AD requires drilling a drainage hole in the elevator pushrod, inspecting the elevator pushrod for corrosion damage, and replacin…

  Federal Register →

• Mar 17, 1998

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Models ASW-19 and ASK-21 Sailplanes

  This document proposes to adopt a new airworthiness directive (AD) that would apply to certain Alexander Schleicher Segelflugzeugbau (Schleicher) Models ASW-19 and ASK-21 sailplanes. The proposed AD would require: modifying the rudder surface panels; replacing the airbrake bellcrank; and modifying the rear canopy hinge structure. The proposed AD is the resu…

  Federal Register →

• Feb 12, 1998

  Airworthiness Directives; Alexander Schleicher Model ASK-21 Sailplanes

  This document proposes to adopt a new airworthiness directive (AD) that would apply to Alexander Schleicher (Schleicher) Model ASK-21 sailplanes. The proposed action would require inspecting the S-shaped rudder pedal tube for displacement, and correcting any displacement of the plastic tube. The proposed AD is the result of mandatory continuing airworthines…

  Federal Register →

• Feb 12, 1998

  Airworthiness Directives; Alexander Schleicher Model ASK-21 Sailplanes

  This document proposes to adopt a new airworthiness directive (AD) that would apply to Alexander Schleicher Model ASK-21 sailplanes that have certain modifications installed. The proposed action would require changing the sailplane flight manual's weight and balance information. The proposed AD is the result of mandatory continuing airworthiness information…

  Federal Register →

• Feb 5, 1998

  Airworthiness Directives; Alexander Schleicher Model ASK-21 Sailplanes

  This document proposes to adopt a new airworthiness directive (AD) that would apply to Alexander Schleicher Model ASK-21 sailplanes. The proposed action would require removing certain pages from the sailplane flight manual and replacing these pages with new pages having different information regarding spin and stall recovery. The proposed AD is the result o…

  Federal Register →

• Dec 19, 1997

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK-21 Sailplanes

  This document proposes to adopt a new airworthiness directive (AD) that would apply to certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK-21 sailplanes that do not have a certain automatic elevator connection installed. The proposed AD would require drilling a drainage hole in the elevator pushrod, inspecting the elevator pushrod…

  Federal Register →

• Dec 19, 1997

  Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK-21 Sailplanes

  This document proposes to adopt a new airworthiness directive (AD) that would apply to certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK-21 sailplanes. The proposed AD would require replacing any tow release cable assembly that does not have a swivel-type end with a cable assembly that does have a swivel-type end. The proposed A…

  Federal Register →

• Jun 7, 1995

  Airworthiness Directives; Alexander Schleicher GmbH & Co. Model ASK 21 Gliders

  This amendment adopts a new airworthiness directive (AD) that applies to Alexander Schleicher GmbH & Co. (Alexander Schleicher) Model ASK 21 gliders. The required action requires replacing the parallel rocker with a part of improved design, and incorporating flight manual revisions. Two incidents of the parallel rocker breaking at the elevator connection on…

  Federal Register →

• Jan 18, 1995

  Airworthiness Directives; Alexander Schleicher GmbH & Co. Model ASK 21 Gliders

  This document proposes to adopt a new airworthiness directive (AD) that would apply to Alexander Schleicher GmbH & Co. (Alexander Schleicher) Model ASK 21 gliders. The proposed action would require replacing the parallel rocker with a part of improved design, and incorporating flight manual revisions. Two incidents of the parallel rocker breaking at the ele…

  Federal Register →

04 /  Service Difficulty Reports

FAA SDR filings

The FAA does not currently expose a public API for Service Difficulty Reports. We do not back-fill or paraphrase. Search the FAA SDR portal directly →

05 /  Sources & Methodology

Every fact on this page links to its primary US-government source

• FAA Aircraft Registry →

  Refreshed May 5, 2026

  Available

• NTSB CAROL →

  Refreshed May 5, 2026

  Available

• Federal Register (FAA Airworthiness Directives) →

  Refreshed May 5, 2026

  Available

• FAA Service Difficulty Reports →

  Refreshed May 5, 2026

  Unavailable

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