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on its own!) landed successfully, while the E90 had the wing come off, crashed and killed the one occupant. In both cases, tests showed that the bolt had been weakened by “stress corrosion.” It was a real fiasco of a time as all bolts had to be pulled and inspected, and more problems were being caused when this was done incorrectly, especially when a washer was installed backwards, gouging the fitting. The outcome was (1) putting the bolts in a lubricated environment instead of “dry,” (2) instituting an inspection and replacement requirement for the bolts, and (3) offering a nickel-alloy “Inconel” bolt that was much more corrosion resistant and allowed longer inspection/replacement intervals. (I doubt that any steel bolts remain in King Airs.)
Saunders jumped into the fray with a very extensive advertising campaign that implied the King Air wing was unsafe without that secondary load path his strap provided. Many, King Airs had the strap added. A Canadian Government flight inspection King Air lost a wing, too. (The strap is very popular in Canada!) Personally, I think it is unnecessary – with proper bolts and inspections – but I have nothing against an airplane with a strap. In fact, unless someone points it out, most pilots wouldn’t even notice it.
I was actually in attendance at a King Air Maintenance and Operation Symposium held at an NBAA convention in the early 1980s. Linden Blue was then the relatively
new president of Beech Aircraft. He was sitting in the back of the crowded room and observing a rather contentious exchange between the Beech customer support people and the somewhat angry operators who were needing assurance that the wing was safe. Mr. Blue stood up, was recognized from the podium, and asked for a show of hands of all of those who would feel more comfortable if there was a secondary load path. Well over half of the hands went up. Then Mr. Blue said something to the effect of, “Well, if so many of you want it, then we’ll provide it for you, using Beechcraft quality design and manufacturing.” You should have seen the look of surprise and horror on the faces of the Beech customer support and engineering people there! After telling people why the strap wasn’t necessary and what a waste it was, their boss had just “endorsed” it and put them on the hook to make one!
So off to the drafting boards they went and came out with the “Beechcraft Center Section Bridge”... they couldn’t call it an evil “strap,” after all. Because of the argument they’d made about the dissimilar metal corrosion concerns, their strap was made of aluminum. Hence, it is about three times as thick as the Aviadesign strap, has a huge fairing that sticks down quite far below the fuselage, and is ugly as sin. To “hurt” Saunders, they charged the same price as his – about $50K, I think – and lost at least that much on every kit.
DECEMBER 2015
KING AIR MAGAZINE • 15