Citations dogged by control problems

 - August 5, 2008, 10:42 AM
It has not been a good summer for the Cessna Citation 650 or 525. Last month, owners of the Cessna 650 Citation VII learned of a proposed AD (Docket No. 2002-NM-332-AD) that would require repetitive replacement of the horizontal stabilizer primary trim-actuator assembly with a repaired assembly. According to the AD, the move is necessary to prevent uncommanded movement of the horizontal stabilizer that could result in reduced controllability of the airplane.

The AD counters an existing Cessna Service Bulletin recommending a one-time replacement. The FAA is proposing a replacement interval not to exceed 18 months and estimates the cost to each of the 285 U.S.-registered aircraft to be $2,276 per replacement cycle, with Cessna providing the parts at no cost to the owner. The FAA is accepting comments on the proposal until September 22.

Before issuance of the AD proposal, Citation VII operators were already left wondering about an incident involving one of their own operated by Thunder Air Charter. On August 9, at 12:14 p.m. CDT, a Citation 650 (N122EJ) experienced a jammed rudder just after liftoff from the Spirit of St. Louis Airport (SUS) in Chesterfield, Mo. Although there were no injuries, the aircraft did sustain minor damage during the mishap. The aircraft was on a positioning flight operating in VMC on an IFR flight plan to Kirksville, Mo. The crew remained in the vicinity of SUS while evaluating the situation and eventually made an uneventful landing there at 12:42 p.m.

In an unrelated incident that occurred on July 22 at about 10:15 a.m. PDT, a Cessna 525 CitationJet (N996JR) ditched in the waters of Penn Cove, Coupeville, Wash., following a loss of elevator trim control, resulting in an uncommanded nose-down pitch attitude. The commercial pilot and passenger were not injured. The airplane, registered to Tango Corp. of Minden, Nev., was operating under Part 91 in VMC on an IFR flight plan from Victoria International Airport (YYJ) in Sidney, B.C., to Gowen Field (BOI) in Boise, Idaho.

According to Dennis Hogen, air safety investigator in charge at the NTSB’s Northwest regional office, the pilot reported that shortly after takeoff, while climbing through 16,000 feet (en route to FL330), the airplane abruptly nosed over to approximately a 40-degree negative deck angle. The pilot disconnected the autopilot, throttled back to idle and attempted to re-trim the airplane. He reported that the cockpit trim indicator was in the full-forward (nose down) position and that neither the manual nor the electric trim actuators would respond to his inputs.

After numerous configuration changes and unsuccessful attempts to regain full pitch control, the pilot elected to ditch. He stated that the airplane hit the water in a wings-level attitude at approximately 100 knots. Everyone aboard was able to evacuate the aircraft safely, and it subsequently sank in 60 feet of water approximately 300 yards offshore.

Hogen said the investigation has been very slow because it took a week just to get the aircraft out of the water. “We’ve stripped out the majority of the electric trim system and are in the process of testing the components,” he told AIN. “I think we’re going down the right track and we have several components in various places around the country for testing. We’re hoping to have a clearer idea of exactly what happened in a couple of weeks.”

Hogen did say the investigation was focusing on electrical components, but he would not comment on whether it might be an isolated incident or a system flaw. “It’s too early to draw conclusions,” he said.

When asked about the incident and a possible relationship with the Citation VII horizontal stabilizer problem, a spokesperson for Cessna Aircraft declined comment on the incident, saying, “It is company policy not to comment on an NTSB investigation.” However, according to a maintenance supervisor at a Cessna Citation service center, the 650 horizontal stabilizer primary trim-actuator assembly is “quite a bit larger than the 525’s, and they are unrelated.”