Aug. 7, 2008

Interactive Quiz #136:
Adrift in an Unstable Sky

In a stable world, the weather is never claggy, airplanes fly upright and avgas is 50 cents per gallon. Sorry, this quiz is in the real, unstable world, so straighten up and answer right.

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.

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1. The term "stability" is tossed about with abandon in ground schools and pilot lounges. Having no opinion about the subject does not display one's neutral stability, but stability about the airplane's longitudinal axis does display its:
a. Longitudinal stability
b. Lateral stability
c. Vertical stability
d. Dynamic static stability

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2. There is no more stable voice in the sky on a rainy IFR night than that of the sleep-deprived radar approach controller working an under-staffed midnight shift. Good controllers can work traffic in their sleep. In fact, some do, issuing clearances in their sleep long after getting off duty. A clearance is:
a. A vector by ATC, for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specified conditions within controlled airspace
b. An authorization by ATC, for the purpose of preventing collision between all aircraft, for an aircraft to proceed under specified conditions within controlled airspace
c. An authorization by ATC, for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specified conditions within Class B, C or D airspace
d. An authorization by ATC, for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specified conditions within controlled airspace

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3. Break out those E6Bs or contact your junior high school math teacher, Mrs. Erstwhile, for help on this one. Here's the problem: You're to fly from Point A to Point B, distance 200 nautical miles. Ignore climbs, descents, turn radius, times in turns or magnetic variation; this problem is far easier. Cruising at 100 knots (TAS) in calm wind, it would take two hours to travel the distance, one-way. Let's add a 20-knot tailwind outbound and the same wind on the nose on the return leg. There's no crosswind component. How long should this 400-nm round-trip take? (Pick the closest answer.)
a. 240 minutes (4:00 hours)
b. 249 minutes (4:09 hours)
c. 229 minutes (3:49 hours)
d. 240 parsecs (4:00 light hours)

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4. Given the time it took to fly the 400-mile roundtrip in the previous question, if your airplane burns (at normal, cruise-power setting) 8 gallons per hour, and avgas is $5.00 per gallon, what color light would the Class D air traffic control tower flash at you if your radio failed, and the controller wanted you to "exercise extreme caution?"
a. Red
b. Flashing red
c. Alternating red and green
d. Flashing white

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5. Same tower as the previous question. En route to your destination airport, you encounter stronger headwinds than expected. This eats into your planned fuel reserve. As the fuel gauge nudges "E," the headwinds, of course, increase. You figure that you have enough to make the runway but really don't want to be vectored for a long final or told to hold. What is the best way to let ATC know that you are low on fuel and would appreciate no undue delays?
a. Say, "Minimum fuel."
b. Declare an emergency: "Mayday."
c. Squawk 7600.
d. Say, "Pan-Pan-Pan!"

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6. Imagine lining up to depart on Runway 18. Tower says, "Cessna 81L, wind 150 at 10, Runway 18, cleared for takeoff." To avoid skipping sideways across the runway, you must apply proper crosswind technique. (Ercoupe pilots, skip to the next question.) You should begin takeoff roll with full (_____) aileron input. As speed increases you should reduce aileron input, because (in part) the crosswind component becomes more of a relative (_____). (Fill in the blanks with the best answers.)
a. left, headwind
b. right, headwind
c. left, tailwind
d. right, tailwind

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7. Define "crosswind component."
a. The wind component measured in MPH at 180 degrees to the longitudinal axis of the runway.
b. The wind component measured in knots at 90 degrees to the lateral axis of the runway.
c. The wind component measured in knots at 90 degrees to the longitudinal axis of the runway.
d. The wind component measured in knots at 90 degrees to the longitudinal axis of the airplane.

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8. Speaking of winds, when tower says, "Wind 150 at 10," the direction is given in degrees aligned to (_____) North, and the speed is given in (_____).
a. True, knots
b. Magnetic, MPH
c. True, TAS
d. Magnetic, knots

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9. The direction of winds aloft are defined relative to True North, but no winds are forecast for altitudes within (_____) feet of the station elevation.
a. 500
b. 1000
c. 1500
d. 2000

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10. This final question is an NTSB Part 830 issue. Refer to the photo below. The hapless pilot of the now devalued Cessna 150 is uninjured. His troubles began aloft when the airplane suffered a flight-control malfunction (or at least that's his story, and he's sticking to it). If an aircraft, indeed, has a flight-control malfunction, the nearest NTSB field office shall be notified when?



a. Immediately
b. Within 48 hours
c. Within 7 days
d. Within 10 days
e. Upon request by the NTSB

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