FAA Aviation Safety 

## EMERGENCY AIRWORTHINESS DIRECTIVE www.faa.gov/aircraft/safety/alerts/

DATE: December 23, 2011 AD #: 2011-27-51 Emergency airworthiness directive (AD) 2011-27-51 is sent to owners and operators of Hawker Beechcraft Corporation Models 1900, 1900C, and 1900D airplanes. Background This emergency AD was prompted by the fo llowing reported problems of the elevator bobweight (stabilizer weight) traveling past its stop bolt, which allowed the attaching linkage to move over-center, reducing nose down elevator control. In one instance, a Model 1900C airplane experienced jammed elevators on take-off after a loud bang was heard in the cockpit shortly after rotation. The flight crew no ticed that they were unable to move the control column to a nose down position. Elevator movement was only available between neutral to full deflection nose up. The airp lane pitch was controlled with the elevator trim and the airplane returned to base, landing safe ly. Upon inspection, mechan ics noticed that the bobweight interconnect link, part number (p/n) 101-524112-1, was upside down and trailing FORWARD from the control column weld assembly instead of trailing AFT as it should. With the link travel over-center, the geometry of the bob-weight was completely changed rela tive to its stop. This condition made the bob-weight hit its stop mid- travel, where it should actually have positive clearance from its stop at the full nose down posit ion. The elevator could now only move between nose full up and neutral. In another instance, on a Mode l 1900D airplane, during the takeo ff roll the elevator controls felt heavy and appeared to be jammed/sticking, requi ring more force than usual to rotate. The crew then aborted the takeoff run. Subseq uent investigation revealed that the elevator bob-w eight attaching link assembly traveled over-center, thus prev enting full nose down elevat or control authority. The Model 1900 airplanes have the same type de sign and thus are subject to this unsafe condition. This condition, if not corrected, could result in reduced nose down elevat or control and loss of airplane control.

Relevant Service Information We reviewed Hawker Beechcraft Corporati on Safety Communiqué #321, dated December 2011. The service information provides information to assist in doing the actions of this AD.

FAA’s Determination We are issuing this AD because we evaluated a ll the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

1AD Req uirements This AD requires inspecting the elevator bob- weight and attaching linkage for correct installation and for damage or deformation to the we ight and/or weight brack et with corrective action as necessary. Interim Action

We consider this AD interim action to addre ss the immediate unsafe c ondition affecting these airplanes. We may take further AD action at a later date. Authority for this Rulemaking Title 49 of the United States Code specifies the FAA’s authority to issue rules on aviation safety. Subtitle I, Section 106, de scribes the authority of the FAA Administra tor. Subtitle VII, Aviation Programs, describes in more deta il the scope of the Agency’s authority. We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “Gener al requirements.” Under that section, Congress charges the FAA with promoting safe flight of ci vil aircraft in air commerce by pres cribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority becau se it addresses an unsafe condition that is likely to exist or develop on products iden tified in this rulemaking action.

Presentation of the Actual AD We are issuing this AD under 49 U.S.C. Sectio n 44701 according to the authority delegated to me by the Administrator.

2011-27-51 Hawker Beechcraft Corporation : Directorate Identif ier 2011-CE-044-AD. (a) Effective Date This Emergency AD is effective upon receipt. (b) Affected ADs

None. (c) Applicability This AD applies to the following Hawker Beech craft Corporation airplanes, certificated in any category:

Models Serial Numbers (1) 1900 UA-3 (2) 1900C UB-1 through UB-74 and UC-1 through UC-174 (3) 1900C (Military) UD-1 through UD-6 (4) 1900D UE-1 through UE-439

2(d) Subject

Joint Aircraf t System Component (JASC)/Air Transport Association (ATA) of America Code 27, Flight Controls. (e) Unsafe Condition This AD was prompted by reports of the elevator bob-weight (stabilizer weight) traveling past its stop bolt, which allowed the at taching linkage to move over-cen ter. We are issuing this AD to detect and correct conditions that could result in reduced nose dow n elevator control and loss of control of the airplane. (f) Compliance Comply with this AD within the complia nce times specified, unless already done. (g) Inspections

Within the next 10 hours time-in-service after receipt of this emergency AD, inspect the elevator bob-weight installation for the following conditions. Use Hawker Beechcraft Corporation Safety Communiqué #321, dated December 2011. NOTE: The term “nose down” corresponds to the airplane nose down, down elevator, and control column forward position as used in this AD and Hawker Beechcraft Corporation Safety Communiqué # 321, dated December 2011. (1) The correct positioning of the elevator control column link assembly, (part number (P/N) 101-524112-1 (1900/1900C) or P/N 101-524112-5 (1900D)) . With the elevator control column in the full nose down position (control colu mn forward), the link must fo rm an angle between the link attachment point at the control column and the bell crank pivot point as shown in the Hawker Beechcraft Corporation Safety Communiqué photo labeled “Correct Link Orientation.” The link should be trailing AFT from the control column assembly. (2) The clearance of the bob-weight stop bolt . With the elevator control column in the full nose down position (control column forward), the stabilizer weight stop bolt must have positive clearance with the face of the stabilizer weight. (3) The condition of the bob-weight and alignment with the stop bolt . Inspect for evidence of scraping along either side of the weight by the st op bolt. With side pressure applied by hand to the stabilizer weight, no part of the stop bolt should protrude beyond th e face of the stabilizer weight on either edge. (4) The condition of the bob-weight support bracket . Inspect for evidence of damage or deformation by contact with the weight assembly. (h) Corrective Actions If any discrepancies are found in the inspections required in paragraph (g) of this AD, before further flight, do the following: (1) Contact Hawker Beechcraft Corporation Technical Support by telephone at (800) 429- 5372 or (316) 676-3140 to obtain FAA-approve d repair or replacement instructions.

34 (2) Incorporate the repair or replacement specified in the FAA-approved instructions. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, Wichita Aircraft Certificat ion Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested us ing the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information dire ctly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local f light standards district office/certificate holding district office. (j) Related Information (1) For further information about this AD, contact one of the following: (i) Paul DeVore, Aerospace Engineer, Wich ita ACO, FAA, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: (316) 946-4142; fax: (316) 946-4107; email: paul.devore@faa.gov; or (ii) Don Ristow, Aerospace Engineer, Wich ita ACO, FAA, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: (316) 946-4120; fax: (316) 946-4107; email: donald.ristow@faa.gov. (2) For copies of the service information referenced in this AD, contact Hawker Beechcraft Corporation at P.O. Box 85, Wichita, Kans as 67201-0085; telephone: (800) 429-5372 or (316) 676-3140; Internet: http://pubs.hawkerbeechcraft.com. (3) You may review copies of the referenced service information at the FAA, Small Airplane Directorate, 901 Locust, Kansas City, Missouri 64106. For informati on on the availability of this material at the FAA, call (816) 329-4148. Issued in Kansas City, Missouri, on December 23, 2011.

John Colomy, Acting Manager, Small Airplane Directorate, Aircraft Certification Service.