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Safety Recommendation Details

Safety Recommendation A-09-121
Details
Synopsis: On June 4, 2007, about 1600 central daylight time, a Cessna Citation 550, N550BP, impacted Lake Michigan shortly after departure from General Mitchell International Airport, Milwaukee, Wisconsin (MKE).1 The two pilots and four passengers were killed, and the airplane was destroyed. The airplane was being operated by Marlin Air under the provisions of 14 Code of Federal Regulations (CFR) Part 135 and departed MKE about 1557 with an intended destination of Willow Run Airport (YIP), near Ypsilanti, Michigan. At the time of the accident flight, marginal visual meteorological conditions prevailed at the surface, and instrument meteorological conditions prevailed aloft; the flight operated on an instrument flight rules flight plan.
Recommendation: TO THE FEDERAL AVIATION ADMINISTRATION: Require Cessna to evaluate and limit the maximum aileron trim deflection on Citation series airplanes to that required to meet the certification control requirements for powered trim tabs, unless there is a design justification to exceed those requirements.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Reconsidered
Mode: Aviation
Location: Milwaukee, WI, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: CHI07MA160
Accident Reports: Loss of Control and Impact with Water, Marlin Air Cessna Citation 550, N550BP
Report #: AAR-09-06
Accident Date: 6/4/2007
Issue Date: 10/27/2009
Date Closed: 1/10/2012
Addressee(s) and Addressee Status: FAA (Closed - Reconsidered)
Keyword(s): General Aviation

Safety Recommendation History
From: NTSB
To: FAA
Date: 1/10/2012
Response: The FAA replied that the amount of aileron trim tab deflection required on the manual trim system installed on the Cessna 550 for a particular condition will be the same for both manual and powered trim tab systems. In addition, the FAA provided information from the flight tests conducted on the Cessna 550 as part of its type certification indicating that the Cessna 550 required 20 degrees of trim tab deflection to trim the airplane with one engine inoperative at the maximum fuel imbalance of 600 pounds, and that the airplane has +/- 20 degrees of aileron trim tab travel. The NTSB has considered the information supplied by the FAA, and we have reconsidered our position. As a result, Safety Recommendation A-09-121 is classified CLOSED—RECONSIDERED.

From: FAA
To: NTSB
Date: 10/4/2011
Response: - From J. Randolph Babbitt, Administrator: The amount of aileron trim lab deflection required on the manual trim system installed on the Cessna 550 for a particular condition will be the same for both manual and powered trim lab systems. We have reviewed the Cessna night test compliance report FT550-6. Stability and Control, dated May 4. 1978. Trim characteristics were found to be in compliance with § 25.161. Flight test data shows that the Cessna 550 required 20 degrees of trim tab deflection to trim the airplane with one engine inoperative at the maximum fuel imbalance of 600 pounds. The Cessna 550 has +/- 20 degrees of aileron trim tab travel. Therefore, it does not have excess aileron trim travel. Further, the certification means of required aileron trim travel is consistent throughout the Citation series airplanes. As there is no service history to indicate an aileron trim issue with other Citation models, we did not review those aircraft in detail. I believe the FAA has effectively addressed this safety recommendation, and I consider our actions complete.

From: NTSB
To: FAA
Date: 11/17/2010
Response: The FAA stated that Cessna had reviewed the flight test compliance report for the Cessna 550 airplane and determined that it does not have excess aileron trim travel. The NTSB is concerned that Cessna's determination is based on application of the requirements in its type certification. The Citation has an unpowered aileron trim system, but the action recommended is to limit the maximum aileron trim deflection to that specified in the certification control requirements for powered trim tabs. This recommendation was issued because the NTSB is concerned that the Citation's aileron trim system allows for trim forces that far exceed those needed during an emergency, such as a loss of engine power. Additionally, because of the relative sensitivity of the small aileron trim control knob, even a small aileron trim adjustment could result in trim forces that would require excessive control wheel inputs to counteract and keep the airplane's wings level. The NTSB concluded that limiting the deflection of the Cessna Citation's manually operated aileron trim tab to the deflection certification limit for powered trim tabs and reducing the Citation's aileron trim sensitivity would help pilots avoid sudden and excessive aileron trim deflections. Therefore, an acceptable response to this recommendation depends on the FAA's planned review of Cessna's conclusion using the standards recommended. Accordingly, pending completion of the recommended action, Safety Recommendation A-09-121 is classified OPEN – ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 4/28/2010
Response: Letter Mail Controlled 5/5/2010 12:17:19 PM MC# 2100167 - From J. Randolph Babbitt, Administrator: Cessna has reviewed the flight test compliance report and determined that the Model 550 does not have excess aileron trim travel. We will review the report and confirm Cessna's conclusion and are considering requesting a test flight to validate trim capability. Once we have completed our review we will determine the appropriate course of action. I will provide an update on the progress of this safety recommendation by March 2011.