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Nov. 1, 2007

## Interactive Quiz #126:Control Input

Ercoupe pilots, cover your ears. The rest of you, please get your feet off the floorboards and help us get a grip on a few questions about control surfaces. Proper input coordination is required.

INSTRUCTIONS: Answer the questions as best you can, then click on the "Score my quiz answers" button to see your score and read the explanations. If you don't like your score the first time around, you can change some of your answers and resubmit. To get the most out of this quiz, we suggest you keep trying until you get a perfect score.

NOTE: When more than one answer is true, only the most complete, correct answer will be scored as correct. The answers are assumed to apply within the United States unless otherwise noted.

1. Back to basics, Mrs. Bernoulli. Please name the three axes about which the airplane rotates.
a. Elevator, aileron, rudder
b. Latertudinal, longitudinal, vertigal
c. Longitudinal, horizontal, vertical
d. Longitudinal, lateral, vertical
2. Building on the previous question, please identify which control input causes the corresponding movement. (You'll know around which axis if you answered the previous question correctly.)
a. Elevator -- pitch; aileron -- roll; rudder -- yaw
b. Elevator -- yaw; aileron -- slip; rudder -- skid
c. Elevator -- altitude; aileron -- rate-of-turn; rudder -- heading
d. Elevator -- vertical-speed indicator (VSI); aileron -- directional gyro (DG); rudder -- turn coordinator.
3. Airplane controls are neatly divided into two categories: primary and secondary controls. Name which control(s) is (are) secondary.
a. Aileron
b. Rudder
c. Flaps
d. Elevator
e. Throttle
f. c and e (flaps and throttle)
4. Spend tens of thousands of dollars to become a CFI and you can get a job asking, "Would you like Frise with that aileron?" A Fries-type aileron pivots on a hinge and, as the aileron's trailing edge goes up, its leading edge scoops below the wing and creates drag.
a. True
b. False
5. Speaking of ailerons, one type of aileron is designed so the up-aileron rises more than the down-aileron descends, thus creating more drag on the up-aileron to offset the increased drag on the lowered aileron. This somewhat offsets adverse aileron yaw. What type of aileron is this?
b. Balanced aileron
d. Differential aileron
6. "Bernoulli's Principal" has often been misidentified as Mr. Ramignolla of Englewood, N.J., High School (1957-1972). A fine educator to be certain, but we want to know about the aerodynamic effect named for Daniel Bernoulli, an 18th-Century Swiss mathematician and non-pilot. Which fragmented answer below best applies to Bernoulli's Principle?
a. An increase in the speed of a fluid (or gas) causes a decrease in the fluid's pressure.
b. A decrease in the speed of a fluid (or gas) causes a decrease in the fluid's pressure
c. An increase in the speed of a fluid (or gas) causes an increase in the fluid's pressure
d. The speed of a fluid (or gas) decreases inversely with the mass of the fluid's pressure squared
7. One for the Piper Cherokee crowd: The tail's horizontal surface that, to us non-Cherokee drivers, looks like a big elevator, has another name. Cherokee pilots get so few chances to crow, so please name that horizontal control surface. (Select best answer)
a. Elevator
b. Stabilizer
c. Stabilator
d. Ruddervator
8. Stick with the Cherokee from the previous question. Along the tail's horizontal surface trailing edge is a moveable tab. What is that tab called?
a. Trim tab
b. Anto-servi tab
c. Anti-servo tab
d. Fleugalator tab
9. Airplane pilots should be familiar with the term "overbanking tendency." While it sounds like a propensity to return to one's bank for more money in support of a flying habit, it actually refers to an airplane's tendency to (you guessed it) overbank in a turn. Complete this sentence: Overbanking tendency is caused by ...
a. The additional drag on the raised wing (the one with the lowered aileron producing all that extra bank)
b. The additional lift on the raised wing (the one with the lowered aileron producing all that extra lift)
c. The reduced lift on the raised wing (the one with the lowered aileron producing all that extra drag)
d. The adverse lift on the raised wing (the one with the raised aileron producing all that extra yaw)
10. Almost done, Mrs. Bernoulli. The airplane's controls include a throttle or two (or eight if you're flying a B-52). Let's assume we're in a Cherokee 180. The lone throttle control connects to the carburetor, which mixes fuel and air before sending it to the cylinders. There, the mixture is turned into power and expelled through four cycles (or strokes) of the engine. Name the four strokes (cycles) of a four-stroke engine.
a. Intake, compassion, power, exhaust
b. Ingest, compression, thrust, repeat
c. Intake, compression, power, exhaust
d. Inhale, compression, surge, exhale

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