One day after thermalling our glider was down to a height of about 2500 feet approaching the airfield. I needed to get us down to below 1000 feet to start a circuit and landing.
I suggested I should fly a few slow circles (losing about 200 feet each time around). But before I started, the instructor quietly asked if I had a strong stomach. I reckoned my innards were behaving, so he announced he would demonstrate an emergency descent. As it was simulating an emergency descent there was no time for the usual HASSELL checks.
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The instructor eased the airbrakes fully open and pushed the stick firmly forwards while starting a right turn and we entered a steep dive. In no time we were about 80 degrees nose down with the airspeed up to about 100 knots. The noise of the slipstream was much louder than usual and the ground was visibly rising to wards us. I thought that this was probably a good imitation of a WW2 Stuka dive-bomber. A constant turn was maintained to keep a lookout on the area of sky below in case of any other traffic. I remembered that the Vne (never exceed speed) of the Puchacz is around 116 knots, when flutter can start and tear the glider apart. And the Va (maximum manouevering speed with full aileron deflection) is only 81 knots. But the Puchacz airbrakes are so powerful that you can almost stand the glider on its nose without over-speeding. I was told that if you find yourself beyond Vne you should only use the elevators to recover as the airbrakes can overstress the wings. As we continued downwards at a fair old pace my eyes kept returning to the altimeter as it rapidly unwound. As we passed 1500 feet, the instructor slowly eased back on the stick and eased the airbrakes closed, and soon we were back into sedate level flight at about 1200 feet. He explained that this technique can be used to get down quickly if (for example) clouds have moved in that are about to eclipse the ground. It is a very bad idea to be caught above a solid cloudbase as you can't see where you or the airfield are, and descending though cloud is an expert technique requiring the use of an artificial horizon (not fitted on the Puchacz instrument panel) or a more basic or turn & slip indicator. Cloud soon disorientates a pilot which can lead to loss of control, and you never know if a cloud has a hard centre (e.g. a mountain or another aircraft). It can also be used to quickly lose excess height if you are close to the airfield and want to land. |