Stalls and PFLs

I took some milk with me when I went flying today. Well, I didn’t actually take the milk flying with me, but rather took a pint of the stuff to the airfield. You see, there is this thing about airfields – none of them have any proper milk. The problem is, when you take milk to the airfield and it doesn’t all get used up, the only option is to put it in the fridge. Which (obviously, doh!) means switching the fridge in in the first place. Then the weather turns and you dont get back to the airfield for 10 days, by which time the milk has gone more off than a very off thing and the fridge has been declared an area of special scientific interest. Not to mention the fact that you’ve now got to pay the electric bill for running the fridge for 10 days to keep a quarter of a pint of mouldy milk cold. All that money could be better spent on actual aviating, so the fridge stays switched off and the coffee gets made with powdered whitener instead. Coffee made with whitener is bad enough, I dread to think what it does to the taste of a cup of tea…

Anyway, enough with the milk rant. Keith decided that the thing to do today would be slow flight, approach to and recovery from the stall and practice forced landings. We got the books out and talked through how a forced landing actually works, the high key point, low key point, the constant aspect relative to the aiming point, etc. We walked 50 yards across the airfield to where there was a concrete tie-down embedded in the grass and spent a few minutes walking around it in ever decreasing circles, crouching down to simulate descending flight and looking at how we could make our perspective view of the concrete block stay the same by turning at a greater or lesser rate. Most amusing for the onlookers, I’m sure, but it was a good way of bringing the text book pictures and white board diagrams to life.

We went out to get the aeroplane checked over and pre-flighted. I was keen to get the checks done and crack on, which was a bad idea. Keith suggested that I think of the pre-flight checks as a list of reasons why we should not go flying, rather than a list of things to do once you’d already decided to fly. Which made sense in an odd way, so instead of saying to ourselves (for example) “do we have enough fuel to go flying?”, we say to ourselves “we can’t go flying because we have no fuel” and then prove to ourselves, by looking at the tank, that we, in fact, do have fuel and it is enough to go flying. We then say “okay, we have enough fuel, but I bet the engine won’t start” – but oh look, we switched both mags on and pressed the red button and it started, etc, etc.

We finally got going, although I seemed to be having trouble remembering which way the rudder pedals worked, the aircraft would swing slightly left and I’d press on the right pedal, making it go further left before pushing (more urgently this time) on the left pedal, over correcting and causing a swing to the right instead, and the cycle repeated.

Edit 06/07: The previous paragraph just serves to demonstrate exactly how confused I got! For the aircraft to turn further to the left, I must have been pressing on the left pedal, instead of the right. The C42 steers the same as any other aeroplane, i.e. press the left pedal to turn left…

It was much choppier on the climb out today as well. The aircraft seemed to want to shimmy this way and that, yawing right and left, pitching slightly up, then down, as we passed through pockets of air that were doing different things. It actually felt as though we were struggling to gain height, but in fact we were just having a slightly bumpier ride than normal – the climb rate, engine note and airspeed were all exactly the same as normal. Ho hum.

We scooted off to Pevensey marshes to try and put into practice what we’d been talking about earlier. It didn’t go too well…after Keith pulled the throttle back to idle, I settled the speed at 60kts and lowered 1 stage of flaps. I then had to keep the aiming point (about a quarter of the way down the field we were going to ‘land’ in) off to my left and below, at my best guess at a 30 degree angle. I then had to use ailerons to initiate a descending turn which would ultimately take us through 270 degrees and onto a final approach into the field. The trick is to keep the aiming point in view at all times, which can get tricky in a high wing aircraft which is banked to the left. If the aiming point is moving down the window, you’re too high, so compensate by decreasing the bank angle until the aiming point comes back to the right place. Similarly, if it goes up the window, youre too low and need to increase the bank angle to get it back in place. All well and good in theory, but when it’s choppy and thermic over the fields, you keep pressing the wrong rudder pedal in the turn, the nose keeps dropping because youre spending too much time looking at the ground, then you sort the attitude and speed out, only to look out the window again and realize you can no longer see or find the field you’re supposed to be aiming for, the workload starts to feel like it’s all getting too much very quickly.
After 3 goes at the field we’d picked, we decided to head off and find another one, this time higher up the South Downs about 600 feet above our nominal ‘ground’ level relative to the 60 feet AMSL that is Deanland. The Ikarus seemed to be having trouble keeping her nose up, needing a considerable amount of back pressure on the stick just to maintain straight and level. I spent a minute on a futile search round the cockpit for the possible source of the problem, without success. I said to Keith that she felt very nose heavy all of a sudden. He pointed at the ceiling of the cockpit, where the flap lever is, and the cause of the problem became immediately clear. After our last PFL, I’d forgotten to put the flaps back to neutral before commencing the climb back up to 1700 feet. As soon as I corrected that, performance returned to normal. Meh…

On the way to the next field, we did some slow speed flight and I had a go at flying the aircraft on the very edge of the stall, just as you would be during the last 2 or 3 seconds before landing. I still kept getting the controls crossed when trying not to let either wing drop in the choppy air closer to the ground. The nose high attitude of the aircraft at that speed felt extremely odd – Keith was paddling on the rudder to demonstrate how ineffective it becomes at slow speed, which in turn made the aircraft twitch and roll slightly and start to feel a bit like a car that’s about to lose its grip on an icy road.

The next couple of PFL went a bit better, although I was still apprehensive about banking the aircraft too much so close to the ground. I have to remember that we’re still at a good 60 kts at that point and the C42 doesn’t even get close to the stall until you get to 40kts.

We headed back towards the airfield, trying desperately to spot a couple of Jabirus that were allegedly joining the circuit downwind at the same time as we were, but failing miserably. I spotted the lake in front of the copse of trees at the start of the downwind leg without any problem this time, which in turn made it easier to track accurately to the base leg turn. The PFLs we’d been doing suddenly started to take on a new relevance as we turned final for Deanlands runway 24, applying exactly the same principles to keep the runway threshold (i.e your aiming point) in sight and at the right angle.

The approach got sloppy again as I tried in vain to juggle airspeed, power and attitude to get us down safely. I seem to be okay up to the point where we’re crossing the fence just before touch down – at that point, I can’t seem to find any useful visual reference against which to judge when to begin the flare. Keith definitely landed the aircraft today, although he gamely tried to tell me I’d done okay!

So, sat in the garden with a cold beer typing this, it’s pretty obvious just how much I still have to learn. Next lesson booked for mid-day next Saturday and Keith tells me he thinks I’m just about ready to start on circuit bashing over at Headcorn. Hmmmm….

Notes to self for next lesson:

  • Try and remember which way the rudder pedals work – left pedal turns you to the left when taxying
  • When it’s time to head back, remind Keith to ask me if I know where we are in relation to the field and see if I can find my own way back without help
  • Try and concentrate a bit more on the landing – ignore the fence, it’s not about to leap up and snatch you out of the air