Saturday, August 1, 2009

Stalls

The mission for today was stalls.

We dispensed with the usual briefing since we'd briefed on stalls on Wednesday and it was rightly assumed that I could remember it.

I was sent out to preflight Jab 5231. Happily, it is possible to move the rudder pedals on 5231. I went through the usual checks and Jeremy came out. He was like "do we have an airplane?" and I was like "well we have two wings and a tail so I reckon we're set!"

We got in and I started it. While I was taxiing Jeremy told me I was taxiing a little too fast (perhaps I have a need for speed?) - taxiing is meant to be done at a fast walking speed but nobody is really sure how they work out what a fast walking speed actually is! We did the various checks at the various points and Jeremy did the takeoff.

We went to the training area and climbed to 3500ft. We were just below the cloud here, so we couldn't go up to 4000ft but 3500ft still gave us enough height to recover from the stall by 3000ft.

First we went through the pre-stall checklist - HASELL. Then Jeremy demonstrated several stalls. To be honest, I expected something a little more scary but it was all pretty tame - although still fantastic fun. You reduce the power to idle (1000rpm) and at the same time raise the nose to maintain height. Eventually (with a lot of help) the critical AofA will be reached and the plane will stall. There is a stall warning horn which sounds when the critical AofA is reached. It's not a particularly scary sounding horn, although it might be more scary for people who didn't know what it meant and weren't expecting it (i.e. passengers).

Before entering a stall, it is important to do a clearing turn. This is a 360 degree turn to check that there is nothing around you and, most importantly, below you.

There are a number of steps to a stall.

  1. Put on Carby Heat to prevent Carburettor Icing (ice in the engine)
  2. Reduce the power to idle (1000rpm)
  3. While reducing power, raise the nose in order to maintain height
  4. The wings will eventually reach the critical AofA and the stall horn will sound
  5. Turn off Carby Heat when the horn sounds
  6. Release backpressure on the stick to allow the nose to lower
  7. Slowly increase power to full and at the same time raise the nose to the climb position
  8. Climb back to previous height
The reason that the plane is put into a climb after the stall, rather than just into a cruise, is in case a stall was entered (either intentionally or accidentally) closer to the ground. You want to climb as fast as possible to avoid trees and other potential things to crash into.

After a couple more demonstrations, I was given a chance to try. The first thing I noticed is that it takes a lot (a LOT) of backpressure to make the plane stall. You really have to force it to stall. When I asked Jeremy about this later, he said that it is due to the design of the plane - the planes are designed to avoid stalls which is a good thing, but also a bad thing training-wise as they want to teach us how to do it so we can get out of it.

One of the main problems I was having when entering the stall was keeping the wings level with the ailerons. It is important to keep the wings level otherwise there is the possibility of having one wing stall but not the other, which can get a bit messy.

I tried a few more stalls but still found it hard to get used to just how much backpressure is needed. I had the stick pulled nearly the entire way back and it still didn't want to stall. The rest of the stages of the stall I found fairly straightforward, although it is hard to remember to put the Carby Heat on - I did one stall and only realised that I hadn't put it on when I went to turn it off!

The visibility was fairly bad today. There were some low clouds and some patches of rain. It was quite bizarre to fly through the rain. We had to keep turning to try and avoid the rain but by the end of the lesson we were definitely running out of clear spaces to go to (which, unfortunately, was the reason the lesson had to end). It was really interesting to see the rain patches from the air though, there were these patches of misty air just hanging there in the middle of the sky.

When Jeremy did the landing today, he had me put my hands and feet on the controls to feel what he was doing. He talked me through the steps of the circuit and the landing, and it was really good to get a feel for what it's like. When on final approach to land, the pilot picks a spot on the runway to aim for - at Lilydale, this spot is generally the brown patch where everyone touches down, which is nice and easy to see from the air. When he is landing, Jeremy said he imagines that the Jab has raised cross-hairs on its nose (similar to WWII style planes) and he places the brown patch in the middle of those imaginary cross-hairs. I will definitely try to remember that idea when I eventually do landings.

Next lesson is going to be a mixture of more stalls and the other maneuvers that we've done so far. This is apparantly in preparation for circuits and learning landing and take off. Before learning landing/take off it is important to have a good understanding of the controls etc, otherwise it can get a bit tricky.

I am still on a headset hunt and today I asked Jeremy for his opinion. He suggested a David Clarke headset which they sell at the airport for $500. I asked his opinion of the LightSpeed Zulu which I've been looking at on the internet. He said it was a really good headset but costs $1,200. I said that price wasn't really a problem since I'm planning for this headset to last me for ages and apparantly the Zulu is a good choice. The Zulu has the Active Noise Reduction which the David Clarke doesn't, which is a good bonus. As Jeremy put it, you only have one set of ears so get the best protection you can! Next Saturday I'm going to go to Moorabbin Airport where there are two pilot supply shops (one with the Bose headset (which Jeremy has and costs $1,500) and one with the Zulu) and have a try-on to test how they feel. Right now I'm leaning towards the Zulu but I'm trying to not let myself be swayed by the fancy gadgets like Bluetooth and music!

Next mission is booked for Wednesday 12th August.

As a side note, who else thinks this is just an accident waiting to happen: http://www.terrafugia.com/
(Disclaimer: I mean no defamation to the company producing the....vehicles....I can, however, see the high potential for misuse by the people who buy them)

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