Service Bulletin on McFarlane Seat Rail

McFarlane

Service Bulletin SB-7, revision A August 20, 2015
Procedures specified in this service bulletin must be accomplished in accordance with accepted methods of aircraft maintenance and applicable government regulations. Appropriate log book entries must be made. COPYRIGHT © 2015

SUBJECT
This Service Bulletin addresses missing seat stop holes from McFarlane Aviation, Inc. seat rail part number MC1210408-22. Methods of identification and correction of the missing hole condition is given. The seat rail is eligible for installation on Cessna model 207 and 207A aircraft with serial numbers 20700563 thru 20700788. The seat rail is installed on the outboard side of the co-pilot’s seat. The seat rails were manufactured by McFarlane Aviation, Inc. between October 10th, 1991 and June 19th, 2014. Note: This Service Bulletin does not affect the aft seat stop hole which is installed in the subject seat rails.

BACKGROUND
Many of the seat rails installed in Cessna aircraft have holes drilled in the vertical web for installation of seat travel stops. The stops are typically installed in both fore and aft locations and serve to limit seat travel during adjustment of the seat location. McFarlane seat rail part number MC1210408-22 was originally designed, approved and manufactured without the two forward seat stop holes. McFarlane has since learned that two forward seat stop holes are needed. Without a seat stop installed in a forward stop hole, it is possible the seat may slide far enough forward to come off the seat rail during seat adjustment.

It is possible that installers of these seat rails have drilled the missing holes to match those of the seat rail being replaced. It is also possible some installers have not installed the stop holes or a forward stop at the proper locations.

This Service Bulletin requires an inspection of the seat rail to determine if a McFarlane manufactured seat rail has been installed. Further inspections are then performed to determine if the missing holes have been created and are correct in size and location. The holes may be added if found to be missing or, in the event field installed holes are incorrect in location or size; the seat track is to be removed and exchanged for a replacement seat rail from McFarlane Aviation Products. Figure 1 depicts the seat rail and associated seat stop with attaching hardware.

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Figure 1. Detail “A” shows seat stop holes properly located in the seat rail. The forward seat stop holes, as shown in Detail “A”, were not installed on the affected seat rails.

 

PART NUMBERS AFFECTED
Only part number MC1210408-22 is affected. The seat rail was produced under the following production lot numbers:

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IDENTIFICATION METHODS
All McFarlane seat rails are marked with their part number and Lot number during manufacture. The markings were applied using either stamped ink, engraving, adhesive backed labels or a combination of these methods. Markings may have been placed on the cabin side OR the floor side of the mounting flange as seen in Figure 2. Markings placed on the “floor side” of the mounting flange will not be visible unless the seat rail is removed from the aircraft. If the markings are not visible, the McFarlane seat rails may also be identified by measuring the thickness of the vertical web as shown in Figure 2. The McFarlane seat rails will have a thicker vertical web than the Cessna manufactured rails.

Note: When identifying the marked part number: the McFarlane seat rail will have a “MC” prefix. For example p/n MC1210408-22 is McFarlane manufactured seat rail while p/n 1210408-22 is a Cessna manufactured seat rail.

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COMPLIANCE
Compliance with this Service Bulletin is mandatory.

APPROVAL
Replacement of the affected seat rails and installation of the seat stop holes as described in Step 3 have been shown to comply with Federal Aviation Regulations and are FAA Approved.

ACCOMPLISHMENT INSTRUCTIONS

Step 1
Identify the seat rail as either a Cessna manufactured seat rail or a McFarlane manufactured seat rail as shown in the “Identification Methods” section.
 If a Cessna seat rail is installed, no further action is required.
 If a McFarlane seat rail is installed, proceed to Step 2.

Step 2
Determine if the Seat stop holes have been installed.
 If the Seat stop holes have been installed, measure their location and diameter and compare to the dimensions shown in Figure 3. The stop holes must be located and have a diameter within the tolerance shown. If the stop holes are present and located properly, proceed to Step 5.
 If no Stop holes are present, proceed to Step 3.
 If the holes are present but do not meet the dimensional requirements of Figure 3 then the seat rail must be replaced. Proceed to Step 4.

Step 3
The stop holes may be added to the seat rail as described below.
 Drill the stop holes, located as shown in Figure 3. After drilling measure the stop hole locations and diameters to ensure they meet the requirements of Figure 3.
 Install seat stop as shown in Figure 1 using hardware specified in the applicable Cessna aircraft parts catalog number P703-12.
 Proceed to Step 5.

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Step 4
Contact McFarlane Aviation for a replacement seat rail.
 Remove the defective seat rail and install a replacement seat rail in accordance with the riveting practices found in FAA Advisory Circular AC43.13-1B Chapter 4. Reference FAA SAIB number CE-90-03R2 regarding fasteners used when replacing seat rails in certain Cessna aircraft.
 Reinstall seat and check for function as per paragraphs 9 and 10 of Airworthiness Directive 2011-10-09.
 Install seat stop as shown in Figure 1 using hardware specified in the applicable Cessna aircraft parts catalog number P703-12.

Step 5
Make appropriate aircraft log book entries

CREDIT INFORMATION
McFarlane Aviation will replace, at no cost, any McFarlane Aviation manufactured seat rail p/n MC1210408-22 with a Lot Number as listed above, and will pay $120.00 for removal and replacement of the seat rail. To receive a replacement seat rail at no cost and compensation for installation the defective seat rail must be returned to McFarlane Aviation. For those drilling the seat stop holes in existing installations of the seat rail, McFarlane Aviation will pay $50.00. A copy of the logbook entry along with the aircraft “N” number must be provided to McFarlane to receive compensation. McFarlane will also pay ground shipping for both the replacement seat rail and the return of the old seat rail to McFarlane. Contact
McFarlane Aviation for further credit and return details.

DISTRIBUTION
This Service Bulletin has been distributed to various aviation publications and to registered owners of eligible aircraft. The latest revision of this service bulletin may be found at www.mcfarlaneaviation.com . If you have received this Service Bulletin and are no longer the owner or operator of the aircraft please forward this urgent information to the current owner or operator. For further information or questions call (800) 544-8594 or (785) 594-2741. All persons are free to copy this information if it is copied in its entirety, with no alterations, substitutions or additions.

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