A beginners guide to aerobatics! (part 1)

[Hunhunter]

Many years ago, I was lucky enough to fly with some fantastic pilots who were flying some equally fantastic planes. I got to my first taste of aerobatics riding in a P40 Kittyhawk with a certain Mr Ray Hanna. Talk about a baptisim of fire! I remember watching the world below tumble about and got my first taste of G, that mysterious force that pins you to your seat, or the roof of the plane if you do it the other way round!

Swiftly winding on 20 years, I am now a pilot myself and still have those memories of being flung around in the back of various warbirds imprinted in my mind. It seemed like a logical step to learn about aerobatics, after all, I can do them quite nicely on a flight sim so it shouldn't be a problem, right??

I went along for my first aero's lesson. The instructor asked me if I had done any before and I told him that Mark Hanna had taught me to do wing overs etc but it was a long time ago. So, we took off in the little Cessna 152 Aerobat and climbed up to about 4,000ft. "Ok, show me a wingover" the instructor said. It was 20 years ago when I last did one and I could remember Mark moaning at me for not being aggresive enough. I dived the plane to about 120kts, pulled up and rolled hard left and gave it a bootfull of rudder. The plane turned sharply round and the nose gradually dropped below the horizon, going into a dive as I levelled the wings and pulled up. I was quite pleased with it. The instructor said it was ok but "a bit aggresive"!!! I chuckled at that one.

Then we moved on to the aileron roll. The planes I had done aero's in before (Pilatus P2 and T28) both had constant speed props, so I never had to worry about what the engine was doing. The 152 has a fixed prop which brings added complications when doing aero's as it is easy to exceed the RPM redline. To start the aileron roll, I dived the plane to 120kts with the power reduced to about 2000rpm. The airflow passing through the prop at this speed actually increases the RPM to about 2300 which is just below the redline. At 120kts, I levelled out into straight and level flight for a few moments and then pulled up to an angle of about 30 degrees and at the same time increased to full throttle. At this stage it is important to return the controls to a neutral position before entering the roll. Once the controls are neutral, full left aileron and full left rudder are quickly applied and held in until the roll is completed. As you enter the second phase of the roll and the plane is rolling and diving, it is again important to throttle back so as to avoid over revving the engine. Once the roll is completed, the controls are quickly returned to the neutral position. The second half of the roll is the tricky bit as you are trying to manage the engine speed and recover from the roll at the same time. On my first few attempts I did one or the other, and it is natural to start the recovery too early. To manage the high work load I found it best to deal with the engine (throttling back) just as the plane passes the top of the roll so all I have to worry about is stopping the roll dead with the wings level. Finishing the roll with one wing down will cost you points in a competition (apparently!) but more importantly you can put the plane into an unintentional stall or spin as you pull up with the plane unbalanced and in a slight turn.

So in a nutshell, the aileron roll goes like this: Throttle back, dive to 120kts, level out, pull up to 30 degrees then neutralise controls, apply full power, full left aileron and rudder, throttle back as plane passes inverted position, as wings level quicly return controls to neutral, pull up to level flight.

I have to admit that I found messing about with the throttle whilst inverted took some getting used to. It wouldn't be so bad if you could just completely close the throttle, but what you are actually doing is just taking enough power off to avoid hitting the redline in the dive. Indeed, speaking to a Pitts Special pilot, he said that if you can do good aero's in a 152 then something like a Pitts would be seem quite easy as all you have to do is make the plane go in the right direction> Now I know why constant speed props were invented!

I'll write some more up when I get time.....Loops and stall turns next!

[adlabs6]

Hehe! Sounds fun HH, look forward to reading some more.