Brainteasers Brainteasers Home »

Oct. 4, 2007

## Interactive Quiz #125: What's Up?

The sky's the limit of infinite possibilities when you don't let terminology and regulations hold you down. Let's dissect a few loftier ones to answer questions that have teased aeronautical brains since before Pratt met Whitney.

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. How high is the sky? That's not the first question, but does bring up the issue of altitudes. We reviewed some altitude terms in the previous Brainteaser (#124) and -- heady from the experience -- we now ask for more. Which type of altitude is defined as, "Height (vertical distance) above an obstacle or terrain expressed in feet above ground level (AGL)"?
a. Indicated Altitude
b. True Altitude
c. Pressure Altitude
d. Absolute Altitude
e. Density Altitude
2. Imagine you're flying a Cessna 172, eastbound, VFR, at 7500 feet in compliance with FAR 91.159's VFR cruising altitude rules. You set the altimeter before departure but haven't spoken with an air traffic controller since. Your route's total distance is 380 nm. Estimated time en route is 2 hours and 57 minutes. Fuel on board: 4 hours 10 minutes. The aircraft color is red and white. According to FAR 91.121, your altimeter setting must be set to the "current reported altimeter setting of a station along the route and within (_____) nautical miles of the aircraft." (Assume plenty of reporting stations en route.) Fill in the blank.
a. 50
b. 75
c. 100
d. 150
3. Maintaining a VFR (or VFR On-Top) cruising altitude of 7500 feet MSL may prove tricky as barometric pressure changes en route. Let's say you fly from an area of high pressure to an area of low pressure and do not change your altimeter setting (set correctly in the high-pressure area). In order to keep the indicated altitude of 7500, and that false sense of comfort, the airplane must (_____).
a. climb
b. descend
c. deviate
d. increase manifold pressure
4. Magnetic dip sounds like a Dairy Queen topping made of iron filings, or a move on that TV hit, Dancing With Old Celebrities. Instead, it refers to some of the quirky inaccuracies of your airplane's magnetic compass -- you know, that thing on the panel where you duct-taped the GPS. Every airplane should have a compass, which is often called a "wet compass" because it's supposed to be full of fluid. Plus, it's supposed to have a compass correction card nearby on which a mechanic has written correction factors for magnetic deviation. Even if your compass calibrates perfectly, it will still misbehave in flight due to magnetic dip. Imagine the following: You're flying eastbound, in the Northern Hemisphere. ATC tells you to "Fly present heading; increase speed to 80 knots, big jets to follow." As you advance the power and accelerate, the compass will swing:
a. North
b. South
c. East
d. West
5. You're still in the Northern Hemisphere, still flying a red and white Cessna 172 and now being vectored for sequence. You're headed north (360 degrees). The radar approach controller says, "Cessna 81L, turn right heading 070." You roll into the turn with perfect coordination of rudder and aileron, establishing a 3-degree-per second rate of turn. The heading indicator is inoperative. You have no GPS. Your only directional instrument is the compass. As you begin the turn from north, you can expect the compass will initially indicate what?
a. a turn away from the actual turn
b. a turn ahead from the actual turn
c. the actual turn
d. no turn
e. an Arctic Tern
6. Many general aviation operations occur inside Class E airspace without any ATC assistance if weather conditions allow. For the private pilot operating VFR (not SVFR) inside Class E airspace in daytime, below 10,000 feet MSL, the minimum flight visibility must be (_____) and at night (_____). Please fill in the blanks.
a. 1 statute mile (sm), 3 sm
b. 3 nautical miles (nm), 3 nm
c. 3 sm, 3 sm
d. 3 sm, 5 sm
7. The same VFR private pilot from the previous question climbs above 10,000 feet MSL. The minimum flight visibility must be (_____) and at night (_____). Please fill in the blanks.
a. 3 sm, 3 sm
b. 3 nm, 3 nm
c. 3 sm, 5 nm
d. 5 sm, 5 sm
8. Inside the lower atmosphere, temperature and air pressure generally decrease as altitude increases. With a standard (temperature) lapse rate, temperature decreases by approximately 2 C (3.5 F) for each 1000 feet of altitude gain. In that same 1000-foot altitude gain, the measurable standard pressure drop would be (approximately):
a. 1 inch of mercury
b. 1 millibar
c. 0.1 inch of mercury
d. No change
9. Here's an item that trips up many flight review candidates and makes for easy pickin's on a ramp check. Imagine: You hold a commercial pilot certificate (applies also to private, sport, and ATP), issued on the last day of the first month of the previous year. It is now, the first day of the last month of the current year. You've made and logged three landings to a full stop in a tailwheel-type airplane, VFR, within the previous 90 days and are about to carry passengers (not for hire) on a cross-country flight at night in the same category and class aircraft. You are taking these passengers to visit your new home after permanently moving from your previous address. From the day you changed your permanent address, how many days do you have to notify the FAA?
a. 30
b. 45
c. 60
d. 90
e. 120
10. You're once again way up high in the rarified upper limits of Class E airspace over the lower-48 United States, where a pilot of an aircraft equipped with a certified transponder is advised -- but not required -- to operate with the transponder (and altitude encoding) on.
a. True
b. False
11. For decades the airplane pictured below regularly flew around the globe, navigating across oceans and deserts using dead reckoning, drift meters and raw navigation skill. All, we might add, without strip-searching passengers. What is this airplane? (Click photo for larger version -- 74 KB.)

a. Convair 880
b. Boeing 707
c. Lockheed 1049 Constellation
d. Lockheed Lodestar

If you enjoyed taking this interactive quiz and would like to see more like it, go to the AVweb Brainteaser page. And if you thought it was unfair, confusing, or a waste of time, we'd like you to tell us that, too. And if you have an idea for a subject that you think would make a good future Brainteaser quiz, be sure to let us know.