In 2017, the owner of a King Air 200 was landing at his home base; when the nose touched down, the aircraft lurched violently to the right. Luckily, he managed to keep the aircraft going straight down the runway with the nose tire sliding sideways! This was a nose-steering failure.
Once he was safely off the runway, he looked up in the nose wheel well and found the bungee clip broken, as well as the housing for the steering bungee. He called me and let me know what happened. This King Air was fairly new to him. Earlier that year I had consulted on his pre-buy and supervised the inspections, so I had some familiarity with his aircraft. There was no damage to the nose gear, but his shop had to replace the nose steering components and install a new nose tire. This meant he and I weren’t going to meet up at King Air Gathering II (KAGII) in Dayton, Ohio, as we had previously planned.
I was scheduled to make a presentation at KAG II in a hangar with a King Air on jacks for demonstration purposes. My talk was on pre-flighting a King Air with a few tips on exactly what to look for. One of the KAG II attendees volunteered his F90 to be on jacks for the demonstration and he was interested in my feedback on his King Air.
Since I was seeing this aircraft for the first time, I did a preliminary walk around and checked on a few things. When I peeked into the nose wheel well, guess what I found? The nose steering bungee clip was broken and the bungee spring was on the verge of busting loose!
Needless to say, I had plenty to talk about that day.
I don’t normally run across failed bungee clips on a daily basis. This was just a coincidence; however, it points to the need to check out your nose steering from time to time.
Expand your Preflight Routine
During your preflight inspection, as you work your way around your King Air, it only takes a moment to poke your head into the wheel well of the nose gear to check the bungee clip and the nose steering assembly. All King Airs have the same nose gear steering setup. The bungee housing is cylindrical with a connecting arm extending forward into the nose gear assembly; it’s always on the left side. On a model 90, as in the photo above, the steering assembly is above the gear door retract mechanism.
The clip has rounded corners that protrude into slots in the bungee housing and should be intact. The slots in the housing should not be enlarged or cracked.
The Bungee and the Clip
Long before people began jumping off tall bridges tethered by a long elastic rope, the word “bungee” was an aeronautical term for “springs or elastic tension devices, as the spring attached to movable controls of aircraft …” (dictionary.com).
The steering bungee is a spring inside a cylindrical housing. A shaft moves through the center of this spring, and operation of the rudder pedals moves the shaft. While taxiing, when you turn to the right, the shaft moves as to compress the spring; this transmits pressure to the steering collar. When you turn left, the shaft pulls on the spring, compressing it from the opposite end; this, in turn, pulls on the steering collar.
The clip has many names – circlip, bungee clip, circle clip, etc. It’s actually “square-ish” in shape with rounded corners that bulge out and fit into slots in the bungee housing. The manual calls it a “retainer,” which is probably the most appropriate name, as it holds the all-important spring (bungee) in place. This clip is crucial. It keeps tension on the bungee spring.
The vibration inherent in flight and in ground maneuvering will eventually cause wear and tear on the bungee clip and the slots it fits into. I’ve seen clips break. I’ve also seen the slots on the bungee housing give out. Since the clip is steel and the housing is aluminum, the clip can wear down the slots over time. If a weakened slot breaks apart, the clip falls out, the bungee spring snaps open and busts through the housing. If this happens, tension is lost and your nose steering goes out the window.
You don’t want a failure like that, and you really don’t want one on landing. You might not be as fortunate as the 200 I mentioned, so please add this simple check to your preflight checklist.
Stiff Steering is Not Normal
I often tell a story of a King Air pilot that grappled with really stiff nose steering. He’d been told repeatedly that all King Airs have stiff steering and you just have to learn to live with it (not true!); but his was really bad and he was desperate for a solution. By the time he got to my shop, he had spent over $4,000 in parts and labor on his nose steering with zero improvement.
I taxied his airplane and the steering was horrible indeed. But then I jacked the nose to take the load off and found the rudder pedals moving freely. So, the problem wasn’t his nose steering, it was his nose gear – it needed grease.
You’ve got to have grease between the nose gear upper casting and the shock absorber tube; but know that grease will never get in there if the nose gear is on the ground. This really stiff nose steering was remedied immediately by properly greasing the strut, with the nose jacked. The pilot was ecstatic. He almost ran his King Air into the dirt median the first time he taxied out but got the hang of it and was amazed at the difference.
Once in a while I find a King Air that steers easily in one direction but gets stiff going the other way. Typically, this is because the bungee spring is dry. Again, grease is the answer.
If nose steering stiffness continues after proper lubrication, I would check the gap between the nose gear upper casting and the shock strut. This is a last resort. Per the maintenance manual, the maximum allowable gap is .015 inches, and in all my experience with King Airs, I’ve found that .015 inches gives the best performance. Tighter settings make the nose steering too stiff, in my opinion.
If, following a gear overhaul, your nose steering is suddenly too stiff, I’d have the clearance between the nose upper casting and the strut double-checked to see if it is too tight. But while you’re at it, make sure that strut was greased with the aircraft on jacks.
In summary, if your nose gear steering is stiff, most likely your nose steering bungee is doing its job but your nose strut needs grease. Your nose gear steering should be smooth and easy. Just be sure to take a look in your nose wheel well from time to time. Check the clip in the bungee housing.
Happy taxiing in your King Air.