Safety Communiqué No. 321 1 of 2

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December 2011 

TO: ALL OWNERS AND OPERATORS, HAWKER BEECHCRAFT SERVICES, 

CHIEF PILOTS, DIRECTORS OF OPERATIONS, DIRECTORS OF 

MAINTENANCE, ALL HAWKER BEECHCRAFT AUTHORIZED SERVICE 

CENTERS, AND INTERNATIONAL DISTRIBUTORS AND DEALERS.

MODELS: All 1900 Models, Serials UA-3; UB-1 through UB-74; UC-1 through UC-174; 

UD-1 through UD-6; UE-1 through UE-439. 

SUBJECT: REPORT OF ELEVATOR CONTROL RESTRICTION

Hawker Beechcraft Corporation (HBC) has received two (2) reports of the elevator control 

system having limited nose-down control during takeoff. In this system, link assembly P/N 101-

524112 connects the control column to the elevator bob-weight bellcrank. This link assembly, 

in each case, was reported to be overcenter, thereby restricting elevator travel. 

Correct Link Orientation Incorrect Link Orientation
Safety Communiqué No. 321 2 of 2

The export of these commodities, technology or software are subject to the US Export Administration Regulations. Diversion contrary to U.S. law is prohibited. For guidance on 

export control requirements, contact the Commerce Department’s Bureau of Export Administration at 202-482-4811 or at www.bxa.doc.gov.

The overcenter condition may be facilitated by a misrigged secondary stop and/or excessively 

worn components in the elevator control system. One report revealed damage to the P/N 114-

524061-21/-35 support structure containing the elevator bob-weight, allowing additional travel of 

the bob-weight. 

Bellcrank/Bob-Weight Damage

The second report revealed an elongated bob-weight bellcrank pivot hole in the P/N 114-

524061-35 support structure. Therefore, it is important to inspect all associated components for 

any abnormal wear or conditions per the requirements in the Maintenance Manual (MM), 

Chapter 5.

If rigged correctly, the elevator control bob-weight will have a 0.56 +0/-0.12 (0.44 to 0.56) inch 

clearance to the stop bolt when resting on the down elevator primary stop. 

If the airplane is parked or moored outside, control locks must be installed as described in the 

MM. When using the control locks, refer to Safety Communiqué No. 1, which was re-released 

in March of 2008. Airliner 1900 Series Model Communiqué No. 91 stresses the importance of 

using control locks and following all cautions and warnings in the MM, and includes the 

following statement: “CAUTION: With the control column pulled to the aft position, allowing the 

control column to free-fall to the forward position can cause damage to the elevator system.”

Mandatory Service Bulletin 27-3739, Flight Controls - Flight Control Column Link Assembly 

Inspection/Modification, provides instructions to inspect the link assembly and modify the 

installation to prevent the bearing from separating from the link assembly. 

Application of proper elevator control system rigging, parking and mooring procedures, as 

defined in the MM, is essential to ensure that the system operates as designed. Proper 

application of defined airplane parking and mooring procedures ensures that the system is 

protected from abnormal forces, such as jet blast, wind gusts, or improper handling. 

HBC has performed testing on the Model 1900 elevator control system and could not duplicate 

the reported condition. For technical questions, please contact Hawker Beechcraft Corporation

Technical Support at 1-800-429-5372 or 316-676-3140.