Sonex Aircraft has changed the wall thickness of the two lower support tubes on all motor mounts from 0.035” to 0.049”. The two lower support tubes run from the lower motor mount pins to the lower fuselage motor mount attachments.
WAS: 3/4" Diameter x .035 Wall 4130 Steel Tube
IS: 3/4" Diameter x .049 Wall 4130 Steel Tube

All motor mounts shipped from Sonex since June of 2005 have this heavier-wall tubing already installed on the motor mount. These are identified on packing lists and labeled with -08 part numbers.

In over 11 years of service (and currently 279 completions), Sonex Aircraft has received a total of 4 reports of motor mount support tubes breaking between the lower motor mount pin and the welded area that picks up the cross-tubes. 2 of these reports were on 3300 Jabiru Engine Std Gear Mounts and 2 of these reports were on 2200 Jabiru Engine Std Gear Mounts. In all 4 cases, these were found during inspections and were obvious with a visual inspection.

All Sonex, Waiex, and Xenos Aircraft that do not have -08 motor mounts installed shall visually inspect the area of the motor mount pins for cracks prior to next flight and at regular intervals not to exceed 25 hours of flight time. If area shows signs of cracks the aircraft shall be taken out of service until suitable repairs have been made.

(update 12.04.09) Alternatively, customers may purchase and install a new -08 motor mount, or make the following upgrade/repair to their existing mount: SNX-Mount-Repair.pdf

SNX-C02-10 NOSEWHEEL PUSH ROD SPRING CHECK:
Sonex Aircraft has discovered that some Sonex and Waiex Kits Shipped before May 1st, 2007 may have included the incorrect Nosewheel Push Rod Springs. All Sonex and Waiex Tri-Gear Aircraft Owners should inspect their Sonex-supplied SNX-C02-10 Springs to ensure they are correct.

A correct Nosewheel Push Rod Spring Installation looks like this: SNXC0210_Correct.jpg

An incorrect Nosewheel Push Rod Spring Installation looks like this: SNXC0210_InCorrect.jpg

If your Sonex Supplied SNX-C02-10 Springs are not installed yet, you may measure the inside diameter to determine if they are correct or not. The correct springs measure over 0.60" on the inside diameter: SNXC0210_Correct_Measure.jpg

The incorrect springs measure under 0.60" on the inside diameter: SNXC0210_InCorrect_Measure.jpg

If you determine that you do not have the correct SNX-C02-10, please send an e-mail to the Sonex Tech Department at: tech@sonexaircraft.com. An RMA Number will then be issued for the return and inspection of the incorrect parts. If found to be the incorrect parts, replacements will be sent to you at no charge.

CHECK ALL WELDED COMPONENTS FOR CRACKS IMMEDIATELY:
All Welded Components should be checked prior to your next flight with a particular emphasis on the motor mounts in the area of the lower mount pin attach points. These should be continuously checked at regular intervals after that, such as at Oil Changes, 25, 50, 100, 500 hour inspections and at Annual Inspection.

Note: A crack in your black powder-coated welded component will show as a bright white/gray line and any separation of the structure will be visible to the naked eye. A flashlight and magnifying glass should be used to assist in the inspection.

Any crack found must be repaired prior to your next flight.

UPGRADE OF SNX-F10-03 ANGLE:
The upper portion of the Seat Belt Cross-Tie Assembly (SNX-F10-03) is made from SNX-Z02-03 Channel Stock. Sonex,ltd suggests that SNX-F10-03 be replaced in all Sonex aircraft with a piece fabricated from 1"x1"x1/8" thick 6061-T6 Angle. This replacement part is installed in the same location and has the same fit and function as the original SNX-F10-03. It strengthens the lower seat attach area especially for those choosing to install the Lowered Seat Modification. The new part number for this piece is SNX-F10-26.

Note: This service bulletin does not apply to the Waiex or Xenos.

CHECK ALL WELDED COMPONENTS FOR CRACKS IMMEDIATELY:
All Welded Components should be checked prior to your next flight with a particular emphasis on the motor mounts in the area of the lower mount pin attach points. These should be continuously checked at regular intervals after that, such as at Oil Changes, 25, 50, 100, 500 hour inspections and at Annual Inspection.

Note: A crack in your black powder-coated welded component will show as a bright white/gray line and any separation of the structure will be visible to the naked eye. A flashlight and magnifying glass should be used to assist in the inspection.

Any crack found must be repaired prior to your next flight.