From: CPA_ATIS@cessna.org (Cessna Pilots Association ATIS) Sender: CPA_ATIS@cessna.org Errors-To: CPA_ATIS@cessna.org Reply-To: Roseann.dreasher@cessna.org (Cessna Pilots Association) Precedence: Bulk To: "CPA ATIS mailing list":; Subject: CPA ATIS 5.04a ----------------------------------------------------------------------- CPA ATIS Vol. 5, Issue 04a Thursday, January 24, 2002 ----------------------------------------------------------------------- This is a special edition of the CPA ATIS, a weekly newsletter from the Cessna Pilots Association. The intent of this newsletter is to bring you news and tidbits of information in a timely fashion in an informal format. If for any reason you choose not to receive this newsletter, please respond to and we will remove your e-mail address from our mailing. For questions about Systems and Procedures Seminars, or for further information, write to Heide Koekebakker . ____________________________________ FAA ISSUES SAIB ON LANDING GEAR ACTUATORS, FORGOES AD AT THIS TIME. . . After gathering information from the field on landing gear actuator failures the FAA has decided to issue a Special Airworthiness Bulletin (SAIB) rather than an Airworthiness Directive (AD) at this time. While non-regulatory in nature an SAIB is the highest level of notification the FAA can give short of issuing an Airworthiness Directive. The problem of cracked actuators has been getting some attention since Cessna issued service bulletin SEB01-2 (now SEB01-2 Revision 1). This service bulletin calls for removal and inspection of landing gear actuators in 172RG, R/TR182 and many 210 aircraft that have more than 3000 hours. This inspection is to be repeated every 500 hours according to Cessna. 210 series aircraft prior to the 1970 model year with the original actuators do not require inspection. However, if the original actuators have been replaced they may have been replaced with actuators that do require inspection. The 177RG uses single actuator of a different design and is not subject to this service bulletin or SAIB. While the FAA is not issuing an airworthiness directive it does say “We believe it is important to emphasize the value of accomplishing the actions specified in Service Bulletin SEB01-2.” The CPA tech staff wishes we could agree 100 percent with the FAA and Cessna’s view of accomplishing this service bulletin, but we can’t. CPA feels that there are problems in several areas: 1. PARTS AVAILABILITY 2. DIFFERENCE IN FAILURE RATES BETWEEN MODELS 3. 500 HOUR INSPECTION NOT NECESSARY PARTS AVAILABILITY. . . If you own a 172RG or an R/TR 182 with a serial number above R18200476 you should know that there are no actuator bodies, p/n 1281001-6 available at this time. This is the part that can develop cracks. Cessna is experiencing delays in getting forgings from their supplier and don’t expect to have any until late March. Even then the number of forgings they expect to receive will not be sufficient to take care of all existing orders. So anyone ordering this $3,255.40 part today can expect months of delays and downtime. Owners that want or are required to do the inspection might want to consider delaying until this part is readily available. At the present time Cessna does have stock on the 1281001-4 actuator body, list $7,750, which is used on 210s s/n 21059551 through 21064135 and P2100001 through P21000150. There is also currently in stock 1281001-5, list price $5,790, which is used on R18200001 through R18200476, 21059200 through 21059550, 21064136 through 21065009 and P2100151 through P21000874. DIFFERENCES IN FAILURE RATES BETWEEN MODELS. . . It is interesting to observe that while there are more 210s flying around with these actuators, the majority of the cracked actuators have been found on the 172RG model, which has the smallest fleet size using these actuators. There can be a number of reasons for this, type of use, security of the actuator, type of pivot assembly, etc. CPA is aware of a fleet operator of 27 172RGs who is finding about half of the actuators in his fleet cracked when inspected according to the SEB. However, none of the aircraft had experienced landing gear failures. A fleet operator of R182 aircraft who puts over 40,000 hours a year on their fleet inspects the actuators for cracks when the aircraft get overhauled every 4000 hours. In all these inspections they have found only two cracked actuators and in all these hours of operation have never experienced a landing gear malfunction due to a cracked actuator body. This organization attributes this success in large part to compliance with Cessna Service Newsletter SNL86-49 which has the actuators attached to the airframe with drilled head bolts and safety wire. This method of attachment keeps the actuator from coming loose. If an actuator becomes loose the play can cause the motion of the landing gear system to stress the housing and cause it to crack. An operator of a fleet of 30 210s has inspected most of his aircraft and has yet to find a cracked actuator. In 20 years of operating this fleet the operator has never experienced a landing gear failure due to a cracked actuator. While the 210 in some cases uses the same actuators as the 172RG and R/TR 182, there are distinct differences particularly in the pivot assembly that is rotated by the actuator. The pivot on the 210 is of a different design and material than those used on the 172RG and most of the R/TR182s. Review of the SDRs indicates a similar pattern. Some reported cracks in actuators used on 172RGs, fewer on the R/TR182 aircraft and even less on the 210 fleet even though there are more of the actuators installed on the 210 than the other two models combined. 500 HOUR INSPECTION NOT NECESSARY. . . When a large fleet operator goes 4000 hours between inspections on each of his aircraft, has no failures of actuators due to cracks and finds few cracks upon inspection, there is no apparent justification for disassembling and inspecting these actuators every 500 hours. In this case the cure would be worse than the disease. Repeated removal and disassembly of the actuators would almost certainly cause more landing gear problems than they prevented. SO WHAT DO YOU DO? It would be our recommendation that operators check the actuators to assure that they are secure and installed with drilled head bolts and safety wire. In addition the actuator installed should be inspected visually for any signs of cracks, damage or leakage. We are loath to suggest that an operator should ignore both a Cessna Service Bulletin and a FAA Special Airworthiness Information Bulletin. However operators might want to factor in to their decision the following: -The risk factor related to injury is extremely low. To our knowledge in spite of the number of gear up landings made over the years in single engine Cessna aircraft over the years for all sorts of reasons, no one has ever been injured significantly. -The failure rates by model as demonstrated by fleet operators of these aircraft. -It is expensive to comply with this inspection. Even if no cracked actuators are found the removal, disassembly, inspection, re- assembly and reinstallation will exceed a thousand dollars at today’s shop rate. FAA Special Airworthiness Information Bulletin CE-02-10 can be found at http://www.cessna.org/members/saibce0210.jpg. Cessna Service Bulletin SEB01-2 Revision 1 can be found at http://www.cessna.org/members/seb012r1.pdf. Cessna Service Newsletter SNL86-49 can be found at http://www.cessna.org/members/service_bulletins/other/snl8649.pdf John Frank mailto:john.frank@cessna.org ____________________________________ AND NOW, A WORD FROM OUR SPONSORS... A listing of all of our advertisers with web sites can be found on our web site by clicking on _______________________________________________________________________ Copyright, 2002, Cessna Pilots Association