These Stainless U-Brackets are direct replacements for the aluminum U-Brackets supplied by the factory with every Challenger, and are far superior in strength.

Extensive mechanical testing has been done, including tension, compression and cyclic load tests, all of which far exceed the initial testing done on the factory-supplied aluminum U-Brackets.  Tension tests resulted in the 1.625" brackets exceeding 8,000 pounds of peak tension force (straight pull) before deformation (60% higher than the aluminum brackets).  Tension testing of the 1.625" brackets at angles between 30 and 90 degrees also exceeded the tests of the aluminum brackets by between 19% and 117%, and compression testing of wing spar brackets exceeded 4,200 pounds.  Cyclic load testing was done first at 85,000 cycles @ 2,000 pounds of tension, with no deformation, cracks or failure.  A second cyclic load test was then conducted for 250,000 cycles @ 2,000 pounds of tension and again resulted in no deformation, cracks or failures.

The Stainless U-Brackets are slightly heavier than the aluminum, but the weight difference is minimal.  Each 1.625" stainless U-Bracket is 2.96 ounces heavier than the aluminum bracket (a set of 4 stainless 1.625" U-Brackets will add a total of only 11.84 ounces to your Challenger).  The 2" U-Bracket is 3.21 ounces heavier than a 2" aluminum bracket (a set of 4 stainless 2" U-Brackets will add a total of only 12.84 ounces to your aircraft).  If you replace all 8 brackets, you will add a total of just over 1.5 pounds to the empty weight of your aircraft (the equivalent weight of about 1 quart of fuel).