Tuesday, March 11, 2014

Going Around in Circles

Going around in circles. Literally, not metaphorically.

Jeff had his first "flying" lesson. Why the quotes around 'flying'?  Simple: we didn't do any.

Here's where I am in the whole Make a Pilot program: I've worked most of the way through the Light Sport Pilot training provided by the excellent iPad app from Sporty's. At the completion of the training, Sporty's will send me an endorsement that will allow me to plunk down a ridiculously high $150 for the privilege of taking the Sport Pilot written test.

That isn't the test that I need to take, though. I actually have to take the Instructor - Sport Pilot written test, and the endorsements are not transferable. To get the endorsement that I need, I will have to work through a series of practice tests using Prepware's online training for the Certified Flight Instructor. Fortunately, the CFI test prep also contains the questions I will need to take and pass the other written test, Fundamentals of Instruction (FOI).  Unfortunately, the FOI test is another $150.


Odd that I don't seem to be rushing into it, eh?

I then need three hours of dual instruction from a CFI qualified to provide it. This is one of the weird things about the current state of private aviation: everyone is willing to bitch about how the ranks of private pilots are becoming dangerously thin, but fire off an email to a flight school asking if they have a CFI on staff capable of providing training and you will be met with stony silence. I have yet to resort to the phone, but past experience tells me that I am likely to get a similar reception.  Everyone wants to gripe about people not being interested in flying; no one wants to do anything about it, even when it's their job to do so.

What this means to Jeff is that he wouldn't be able to log any hours that we fly, but that doesn't matter to him all that much since he won't be paying for them anyway. I can apparently give dual instruction in my plane (once I'm certified), but I can't charge for it. That has to do with the nature of the Experimental category that the RV-12 falls into.

None of that matters right now, because he can't even taxi the airplane yet.  Well, I guess I should say "couldn't," because he can now.  It was too windy to fly last night, but the weather was nice and we needed to spend an hour taxiing around the hangars sooner or later anyway, so we did.

There is one thing you need to understand about taxiing an airplane with a free swiveling (as opposed to a Cessna or a Piper which have steerable nose wheels) nose wheel: it's hard to do. The closest comparable life experience you may have is steering a sled, and even that works in the exact opposite direction. To turn left on a sled, you press forward with your right foot. To left left in an airplane, you push forward with your left foot. If that's not complicated enough, in an airplane with a swiveling nose wheel, you can push that left foot as far as you want and nothing will happen, at least not at speeds too slow for the rudder to be effective. Instead, you steer by applying the brakes.

Most airplanes have what is called "differential braking," which boils down to meaning that there is a brake on each side of the landing gear and they can be applied together or separately. They are applied by pressing forward at the top of the rudder pedal - the rudder pedals are hinged at the bottom so that the tops will swivel forward. So, if you want to make a left turn, you either jab at the left brake, or if you are moving fast enough, apply light pressure to the left brake.  One of the challenges is learning which technique is applicable: if you jab, you risk applying so much braking that the plane stops. If you use light pressure, you run the risk of it not being enough and having the airplane get away from you.

Another challenge is that the airplane does not want to track straight and true of its own volition, especially when the winds are up. The wind will hit the side of the rudder/vertical stab and rotate the plane. You have to be ready to counteract that.  Also, once in a turn, the plane typically won't center itself; it takes opposite side brake pressure to straighten it back out.

A typical turn to the right will require pressure (jab or drag) on the right brake/rudder pedal to start the turn. When the correct degree of turn has been achieved, it will take left brake/rudder pressure to stop the turn. You actually have to lead that a little bit because the response is not immediate. Learning the timing and feel for all of this is much harder than it sounds.

I think it was about forty-five minutes of looping around the hangars before Jeff got comfortable with it. There were a number of times when the plane got away from him and he exacerbated the problem by jabbing at the wrong brake. When that was starting to appear chronic, I had him stop the plane so I could take a few minutes to ask him to think a little differently about it. Once I vocalized the difference between "sled" steering and differential braking, the problem was solved.  All we had to do was finish the loop around the hangars and we would be done for the night.

That's when it happened.

We were taxiing along at a pace no faster than a brisk walk when we heard a sound that clearly wasn't normal. It sounded as if we were dragging a chain link fence underneath us. I had Jeff stop and shut down the engine so I could climb out and take a look. All appeared normal until I saw a little metal piece painted the same color as the plane sitting on the taxiway. It was one of the two anti-spin doohickeys that keep the nose wheel axle from spinning. The rivets were sheared completely off.

I pulled the plane forward and the awful cacophony from the nose wheel told be all that I needed to know: at least one of the bearings had seized. We taxied very slowly back to the hangar and put the plane away.

While I had Jeff there to help, I got the nose up on a jack so we could spin the wheel.


Yeah, that ain't right.

So, two bearings are on order from Matco (part number MSC 1628DCTN, $15.60 each) and expected to arrive in a couple of days. In the meantime, I have the wheel off and the tire/tube removed.  The bearings are a press fit and it takes an arbor press to remove them, but quite fortunately I ran into someone at the airport today that has access to such a tool. He should be able to get the old bearings out and the new ones in.

Worst case is I just buy a new wheel: $79.

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