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What do you guys say we do an aileron roll?

Now, I'm going to start by saying that if you try this in a regular airplane, you'll probably kill yourself, and destroy a perfectly good normal- or utility- category airplane.

Before commencing any aerobatic maneuver, ask yourself, "Self, have I met or exceeded the following legal and common sense requirements:

1) Airplane in airworthy condition with no squawks, aerobatic category, rated to perform the intended manuvers AND loaded within the CG envelope for aerobatics. For our Aileron roll, the Citabria with two pilots and chutes and about half fuel will meet these requirements.

2) Each occupant wearing an approved parachute packed by an appropriately certificated parachute rigger within the last 120 days. Our chutes are nylon, so 120 days, if silk, 90 days.

3) Adequate weather conditions, including ceiling. Despite the temptation to fly aerobatics in the path of a hurricane, don't. Legally you are required to be at a minimum altitude of 1500 AGL (above ground level). Common sense says you need about 5000 feet: if you make a mistake you will want every foot of that.

4) WHERE to fly aerobatics: not within 4 miles of the centerline of a federal airway, not over any congested area of a city, town or settlement, and well away from any open air assembly of persons. Thinking of impressing the Dallas Cowboy Cheerleaders with a low-level Immelman turn in your Cessna 150? Forget it!

(Are you getting a sense of why it's so difficult to get your pilot's license? You don't just have to learn to fly the plane, you also get to memorize a few hundred regulations! All designed to keep the skies from looking like the public roads!)

Now, we're ready to fly. We climb in to the Citabria, one in the front seat and one in the back. Master ON. Rotating beacon ON. Mixture full RICH. Aux fuel pump on for 3 seconds to prime, then off. Mixture full LEAN. Open window, verify that no mechanics or innocent bystanders are in the propeller arc, then shout "CLEAR". Left magneto ON, hold brakes, stick back, engage starter. As soon as engine catches, mixture full RICH, right magneto ON. Verify oil pressure within 10 seconds. Aux fuel pump ON. Radios ON. Release brakes, roll forward a couple feet, then apply brakes to check. Taxi to runup area. Swing tail around so that you don't blast guy in Cessna 150 patiently waiting behind you. Throttle 1800 RPM, left mag OFF, verify max drop 125 rpm, then ON. Repeat with right mag. Verifiy max difference 50 rpm. Alternate air HOT, verify 100 rpm drop, then COLD. Oil pressure in the green. Fuel pressure in the green. Aux fuel pump OFF, fuel pressure in the green, then ON. Landing light ON, verifiy ammeter deflects, then OFF. Throttle to idle, verify 600 rpm. Verify controls free and correct. Tune radio to CTAF, announce intentions in the blind: "Anytown traffic Orange Citabria departing runway 24 eastbound departure Anytown."

Still with me? Check base/final for any traffic, then taxi into position on the active runway. Align airplane with centerline, then hold brakes. Throttle to the stop. Verify static RPM 2550, oil pressure green, fuel pressure green. Release brakes. Correct for torque effects with rudders (easier said than done!). At 40 mph, say, to no-one in particular, "airspeed alive," forward stick to raise tail. At 60 MPH check oil and fuel pressure in the green, rotate with back stick to nose-up attitude and you're flying.

Still with me? Climb out at about 70 MPH and depart the traffic pattern toward the aerobatic area. Once you have it located, check all the engine instruments and verify you are level at 5000. You then do a "clearing turn" which is a minimum 180 degree change in direction, all the while scanning for other aircraft that might be on a collision course. Once the area is clear, let's warm up with a "roll reversal" which is basically a 60 degree, 720-degree turn to the right, followed by a roll at maximum rate to the left into a 60-degree 720 to the left. This way, you get a sense of how long it takes the airplane to roll 120 degrees, and the full aileron roll is going to be three times that long. Also, you pull about 2.0g in the 720, which gets your body acclimated to the g's and prepares you for the serious task at hand.

Now let's do it: zero the accelerometer (the g-meter) and climb back up to 5000 feet if you lost any in the 720's. Another clearing turn, looking high and low for traffic. Once clear, let's do the maneuver, progressing to each successive step ONLY if we have accomplished the preceding step EXACTLY. If any step is incorrectly done, we abort the roll. Ready?

Set power for 120 mph. Set trim slightly nose-down, so that you have to hold slight back stick to maintain 120 mph. Verify 5000 feet reference altitude. PULL smoothly up to about 15 degrees nose-up pitch, about 2.5g should do it. If you do it slower, you will lose more airspeed before the roll begins, making it sloppier. Once established on the pitch-up, smoothly apply FULL left aileron (by pushing the stick ALL THE WAY to your left knee) and HOLD it there. Also, to enter the roll cleanly some left rudder will be required: the Citabria has big ailerons that deflect equally up and down. When you put in left stick, the left deflects up and the right deflects down. Lift decreases on the left wing and increases on the right wing, and the airplane rolls about its center of pressure to the left. But when the right aileron deflects down, that wing generates more lift, which also generates more drag, which will tend to yaw the nose of the airplane to the RIGHT. This is called "adverse yaw" and is more pronounced in old designs like our Citabria. You MUST counter it with left rudder. Do you still have that stick all the way to the stop? In the time it took you to read that, we've rolled inverted.

Don't just sit there gawking at the horizon upside down, keep that stick in! A common error is to become so fascinated with the inverted landscape that you take the stick input out, and roll rate slows down. As you roll through inverted, RELAX that back pressure, remember the back pressure I told you to hold to keep the airplane level? Since you are inverted, this down elevator will tend to keep the nose pointed skyward, minimizing your altitude loss. Also, you may generate some negative g here, so don't be surprised if every speck of dirt and dust comes up from the carpeting at this point and gets in your eyes! Keep that stick input in, we're almost around! Do NOT apply back elevator until we have achieved wings-level. There. Now, we're wings-level with about 15 degrees nose-down pitch. Smoothly pull back on the stick, about 2.0g should do it, to return us to level flight.

Congratulations, you just went upside down and lived to talk about it!

In the next installment. . . how to LAND this thing. . .