Tuesday, 2 September 2008

CPL day 6 (good day, bad day)

Monday and a fine sunny start to autumn - perhaps this is the Indian Summer I've been hoping for... No (well not yet) - a band of very heavy rain associated with a cold front sweeping in over Scotland. But if I was lucky I'd get in a sortie before the rain hit, so I hot-footed it over to the airport.

Checked out the aircraft as black clouds started to loom in and headed off to go general handling while the weather was still good. Started with stalls which didn't go very well :-( They're not something you ever really practice except while initially learning to fly to get your PPL.

The basic stall is done in straight and level flight with a clean aircraft (ie. no flaps or undercarriage). In this you pull the power back to idle and keep pulling back on the nose to maintain your starting altitude. The stall warner then goes off and continues to beep continuously while you continue to haul back on the controls (you're really hauling back a lot now). Then the aircraft starts to shake a little as you reach the stall buffet, but you still keep pulling back until the instructor tells you to recover. Then you're supposed to shove full power on and lower the nose to just below the horizon and then as soon as you start to see the airspeed increase again, you bring the nose back up to minimise your altitude loss. You're supposed to achieve this with a loss of less that 100 feet. However, I didn't really get it right in the three goes I had because I didn't bring the nose up soon enough and lost somewhere between 150 and 300 feet :-(

The other two stalls are initiated in the same way, but are in a landing configuration, either with full flap, straight and level to simulate final approach, or with two stages of flap and with a 20 bank to simulate a turn onto finals. In both of these you can't afford to put the nose down to gain speed or you risk planting it firmly into the ground! So at the first sign of stall ie. the stall warner, you shove full power on, lower the nose a fraction to unstall the wing and as soon as airspeed starts increasing you take away drag flap (if you have full flap) and then as speed builds and you start to climb away you bring up the rest of the flaps in stages. The aim being to lose no height, but I again did a shoddy job and still lost height. Still, I'll get more chances to get it right when I do stalling in the twin.

Once we'd finished the stalling we climbed up to 2000 feet and he suddenly chopped the power. Oh no - an engine failure... panic, panic! Well, not really that bad, but even a PFL does get the adrenalin going. I think we did about 3 or 4 and sadly I would have died in nearly all of them :-(
I can't remember the details, but I learnt a few important things:
  • You need to get the carb heat on straight away as if you have carb icing (the most common cause of engine stoppage in the UK) if can take a few minutes for the ice to melt before you would have any chance of restarting the engine.
  • Get your vital actions out of the way (trim for best glide, carb heat, mixture rich, fuel pump on, change tanks) so you can make a Mayday call ASAP. It's ok if you're in an area of good radio coverage like the Vale of York, but if you're over the Scottish Highlands you need to be at a decent altitude to ensure your mayday is received or you won't get any help when you're broken in a broken and/or burning aircraft!
  • When you're pretty low (< 500 feet) and the field you've chosen looks good, you're probably too high. In my last attempt I thought I was ok, but he said I was too high and then proceeded to do a couple of proper S turns at 60 degrees of bank to lose the height and by then we'd got down to about 200 feet and we would still have gotten in. I would still made the field, but in the middle rather than near the start which would have left me little or insufficient braking run.
Again the instructor was happy enough though I wasn't and was a bit down about it afterwards. But fortunately that was the bad day part; I got to fly again that day and had a pretty good one as the next post explains :-)

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