Still, owners report that staying within the CG envelope is not a problem. As for ergos, the cockpit and panel controls are laid out so that everything falls easily to hand. You fly solo from the front seat and visibility is fair in flight. The front stick length gives just the right leverage for the control gearing, especially with aileron spades. The rear stick is short and instructors report that it often takes both hands to get full aileron deflection in a roll in a non-spade aircraft.
Each throttle one for each seat is where one reaches almost unconsciously with the left hand; the carb heat knob is immediately below. Front seat travel is limited and short pilots may have difficulty getting full rudder throw without using an extra back cushion. Citabrias and Decathlons are some of the better airplanes for tall pilots—the high roofline means not having to bend over to look out the side windows.
The panel is low and slender, making installation of more than basic VFR instruments and radios challenging. Headsets or ear plugs are a must as the cockpit noise level is about on par with the proverbial boiler factory. The fuel system is utter simplicity, with three sump drains, one direct-reading mechanical gauge in each wing root and a simple fuel selector.
The covering is Dacron, which is durable, although not good forever. Most owners suggest keeping the airplane out of the sun and we concur. Owners and mechanics familiar with the type tell us that aside from making certain the ADs are complied with, especially AD R1 on wooden spar airplanes, a serious look at all of the fuselage tubes, especially those aft and low, for corrosion and proper inspection of the wooden spars, there are no particular trouble spots to watch for when shopping for a used Citabria.
Early model wing struts had thinner, 0. AD called for replacement of the old struts, and most if not all airframes should have the heavier struts installed; the presence of a placard limiting speed to MPH is proof of the thinner struts.
Also watch for cracked seatbacks. The landing gear U-bolts can develop cracks, especially in airplanes subjected to rough fields or training. Wing damage repair is not always recorded in the logbooks, so inspect any Citabria for wing repairs, especially, as the experts tell us, because most wood spar compression cracks can be traced to an impact event, usually from a groundloop.
The new wing structure was developed as the result of cracks in Decathlon wing spars, not those of the Citabrias, so the presence of wood is not necessarily a deal-killer.
Newbs can get sloppy and blast right through redline airspeed, so a buyer should assume that an airplane capable of aerobatics has been doing them and that pilots have made mistakes in the process, so inspect the wing and tail carefully.
Avoid ones that have been neglected. There are plenty of resources along the way. First and foremost, of course, is American Champion. We like the fact that the factory puts a number of its service bulletins and technical information on its website as a free service. CP Aviation also offers aerobatic training in Citabrias and Decathlons.
The site has training, operating and parts manuals for sale, plus it has a member forum. We have long used the Citabria line as a shining example of good tailwheel handling.
This was confirmed by our review of the most recent Citabria accidents. Thirty-four percent involved runway loss of control—all but a few on landing. Eight Citabrias flipped over due to overly enthusiastic braking on landing or rejected takeoff or picking the wrong surface on which to alight.
Accordingly, two out of every five Citabria accidents involved loss of control while the wheels were in contact with the ground—something we think deserves respect on the part of a pilot considering a purchase. Looking more closely at the RLOC issue, the overall numbers are slightly above what we expect to see for a tailwheel airplane. However, about a quarter of the accidents involved training.
We also note that the Citabria has a much lower rate of accidents involving a nose-over due to over-braking or runway surface than its peers, the Super Cub and Aviat Husky. We attribute that to landing gear geometry. We were pleased to see a very low rate of engine power loss accidents. There were only six, although three were unexplained as they could not be duplicated afterward. There were five carburettor ice forced landings.
Citabria stall behavior is docile, so we were a little surprised to see 11 stall-related accidents until we noted that more than a third came about when the pilot was flying low and maneuvering aggressively, including doing low-level aerobatics. Fun to fly airplanes seem to be directly connected to crashing while flying low—often due to hitting power lines.
Sadly, two pilots hung cameras on their Citabrias to record their low-level flying. Their heirs got to see the videos. One pilot used his Citabria to assist with a cattle drive. He made four passes before hitting power lines and crashing.
A pilot who drifted left off of the runway during takeoff kept going—and drifting left—until he smacked into a hangar. I have owned several taildraggers including a Super Cub. My first was a model with a HP engine and my current airplane is a model with the same powerplant.
Assemble spade plates to the arms with screws, washers and self locking nuts such that the heads will be toward the ground when installed on the airplane.
Remove the AN3 bolt that attaches the aileron pushrod at the aileron. Install the spade arm through it's lower hole with a bolt one dash number longer than bolt removed making sure to reattach the pushrod back in the arm as it was previously.
The spade assembly will hang freely on this bolt until the bolt is tightened. Tighten the attach bolt until the spade does not freely move, back to same torque as the bolt removed before. The arm should be able to be moved by hand to set the proper angle. Clamp the 2 lower ailerons in the position they are in when flying the airplane hands off.
This should be both in exact trail to the wing trailing edge. But, if not, shim and clomp them in the proper location. Using the smart level placed on top of the spade plate under the wing, set the spade angle to the longeron angle plus 2 setting Make sure the attach bolt is tight enough that the spade will not move when drilling the top holes in the aileron arm.
Drill the top hole in the aluminum aileron arm. An angle drill or long drill bit works for this. Drill from each side, then through all. Deburr the newly drilled holes. Install spacer in aileron arm above pushrod centered on newly drilled hole. Install top bolt thru the spade arm, aileron arm, spacer, secure with washers and nut as needed.
Recheck spade angle. The linkage should be straight and 90 degrees to the aileron hinge line. Once I have the slot location figured out, I draw a rough sketch on the inside of the hatch cover centered on the servo spline. To support the hatch cover, I use lite-ply to line the servo compartment opening.
Here you see some balsa strip material glued to the lite-ply cross piece to form the opening. Once this is all done, I place the hatch cover also made of Lite-ply , in position and I trace the clearance around the opening.
This is to determine the placement of the servo and its supports. Here I am making sure the servo arm is centered on the slot guideline which lines up with the aileron control linkage.
A Heavy Duty Du-Bro servo arm is being used. I use a Moto-Tool and a round bit to cut two holes at either end of the slot. I then use a hobby knife to cut the slot between the two holes. A little sandpaper makes the slot neat and clean. Here the hatch and servo have been installed and screwed into place.
You will need to determine the length of the slot by using your transmitter to move the servo arm back and forth.
You can see I had to make a little clearance in the lite-ply support cross piece to clear the servo arm. To complete the control linkage, I use a scrap of wood and a couple cloth pins to center the aileron. The servo hatch is now screwed into place with cap head sheet metal screws. You can also used flush fitting counter sunk wood screws if you like. For smaller airplanes, four screws one in each corner will be enough.
Also here you see the clevis at the servo has been soldered to the control linkage wire. I use Stay-Brite high silver content solder for all my control linkage soldering. Give it a try, it looks much neater than just having the servos sticking out of the wing. I have been installing servos this way for years and even updating older designs such as the Pica WACO.
Great method.
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