[WebMaster]

Report from the Cessna 336/337 SID meeting in Wichita December 2 & 3, 2009.

The meeting started with the distribution of a draft proposal for the Corrosion Prevention Program. These consist of 5 drafts called “Inspection Operation” and they are differentiated by calendar requirements. The first inspection is performed every 12 months, the second every 24 months, then 36, 48 and finally 60 months for the 5th inspection. There are 28 inspections contained in these 5 Inspection Operations. All of these inspections are basically visual inspections looking for signs of corrosion. Most of them can be done with or during the annual/100 hour inspection. There are 2 or 3 that will require some additional work that would not be done during the normal annual inspection. One requires removal the rudders to accommodate the removal of the elevator. This is probably the most labor-intensive part of all 25-inspection areas in the CPCP program. This particular inspection is targeted for every 24 months. The corrosion prevention program is voluntary but if implemented it will decrease or eliminate the need to repeat SID inspections based on calendar. The SID inspection would be based only on hours operated if you chose to follow the Corrosion Prevention and Control Program (CPCP).

After spending most of the first day on some background information and the CPCP program there was some time at the end of the day to start reviewing the 2nd draft of the Supplemental Inspection Documents (SID). Most of the original SID’s were revised with the correct part numbers and application to the correct model Skymaster.

The second day started with continuing to review the 2nd draft of the SID documents. Just as the 1st group of draft SID’s the wing attach and strut attach point inspections were included in the 2nd group of drafts. These two inspections are the most costly to perform and caused several hours of discussion amongst the group. Cessna engineering based all Skymaster SID’s on Service Difficulty Reports (SDR) that had been submitted to the FAA by maintenance personnel over the last 35 years. There are no SDR’s pertaining to the attach points of the wing or strut on 336/337 aircraft. There have been some cracks in the beam of the struts on some high wing strutted Cessna but none at the attach points. There was no resolution achieved concerning the future of these two inspections but Cessna Customer Service is looking into the concerns that were presented by SOAPA and other operators of Skymasters.

There were 24 SID’s proposed in the 2nd group of drafts. Of those 24, 5 may be eliminated. One was revised and eliminated by combining it to a different SID document. One is for 336 aircraft only, front engine tubular mount. One will reference the wing AD that already exists. This leaves around 18 SID’s so the group made some progress.

Cessna then presented the implementation plan for the SID and CPCP programs for the 336/337 series of aircraft; they will be rolled into a new Service Manual and in a new format called ATA. There was much discussion and question about the implications to operators of this approach, as to whether it would make the inspections mandatory at annual or 100 hour inspection time (even possibly for US Part 91 operators). The answers were unclear and seem to depend on interpretation of the FARs. There is concern that this lack of clarity may mean that many IA’s err on the side of caution and insist on these inspections (for inspection sign off) even though they may not legally be required to do so.

What happens from this point is in the hands of Cessna. The Cessna Customer Service side seems sympathetic to our concerns to soften the burden or at least take another good look at the program and how it will affect the fleet. Cessna engineering, on the other hand, is saying the program is rolling out July 2010 starting with the 336 aircraft and moving to the remaining 3 337 models consecutively. They give operators a 15-month window to comply from the release date of the affected model. That gives most operators about a 24-month window from today.

The fact that this Skymaster program will be the foundation for every high wing strutted Cessna aircraft, may constitute a closer look at the common engineering philosophy that Cessna has been taking on these Aging Aircraft Programs. The piston engine, high wing aircraft program may require the Cessna Engineering Department, with their normal jet/turbine philosophy, to change their approach. When they implemented the 425/441 programs, the inspections were in the 10-25% of aircraft value range based on estimated cost to comply versus estimated market value of the aircraft. The Skymaster program does not have the same balance, cost of inspection versus value of the aircraft as the previous programs that Cessna has developed, particularly with inclusion of a few of the more onerous (and arguably unjustified) SID’s. SOAPA is doing it’s best to convey the message to Cessna that consequences of this program may be detrimental for the fleet. These consequences may apply to not just the Skymaster fleet, but rather the entire piston engine Cessna fleet once the programs are extended further to other series of aircraft, as they intend them to be.