Test Pilot

GENERAL

1. What is the difference between a controllable-pitch and an adjustable-pitch propeller? (Neither is a constant-speed propeller.)
2. How did the helicopter get its name?
3. The Beech Bonanza Model 35 has a V-tail configuration with ruddervators — control surfaces that combine the function of rudder and elevator. What are elevons, and on what type of aircraft are they most frequently found?
4. Carburetor ice can form when the outside air temperature is substantially warmer than 32 degrees F. What causes the temperature to drop so dramatically in the throat of a carburetor?
5. From reader Ward Miller: What is the origin of the term, dead reckoning?
6. A pilot performs a 90-degree climbing left turn, during which airspeed steadily decreases to near stall and bank angle increases steadily. The aircraft is then made to transition into a 90-degree descending left turn during which airspeed steadily increases and bank angle steadily decreases. This maneuver is called a _________.

MULTIPLE CHOICE

7. When flying over relatively flat terrain, the lowest altitude at which a jet stream can be encountered is
   1. 20,000 feet agl.
   2. 10,000 feet agl.
   3. 5,000 feet agl.
   4. zero feet agl.
8. A pilot overflying desolate terrain notices a downed airplane with two people waving near the wreckage. In the snow near the wreckage a large letter X has been carefully trampled by the survivors. This signals that
   1. assistance is already on the way.
   2. a landing should not be attempted there.
   3. food and water are required.
   4. medical assistance is required.
9. The most northerly civilian airport in the world is in
   1. Canada.
   2. Greenland.
   3. Norway.
   4. Russia.

TRUE OR FALSE

10. Manifold pressure gauges are required on airplanes powered by piston engines and equipped with constant-speed propellers.
11. The effect of magnetic dip is offset somewhat by the addition of a small weight to the south pole of aircraft compasses destined for use in the Northern Hemisphere. Similarly, a small weight is added to the north pole of compasses intended for use in the Southern Hemisphere.
12. A reciprocating aircraft engine remains stationary inside its cowling, and the crankshaft (to which the propeller is rigidly attached) turns within the engine. There were popular aircraft engines, however, that operated the other way around. The crankshaft remained fixed in position (rigidly attached to the airframe), and the engine (to which the propeller was rigidly attached) did the turning.

ANSWERS

1. The blade (pitch) angles of a controllable-pitch propeller can be changed in flight. The blade angles of an adjustable-pitch propeller can be changed only on the ground, by using tools. In each case, blade angles remain subsequently fixed irrespective of power and/or airspeed changes.
2. Helicopter comes from the Greek words helikos, which means spiral, and pteron, which means wing (thus, a spiraling wing).
3. Elevons are control surfaces that combine the functions of ailerons and elevators. They are most commonly found on delta-wing airplanes that do not have conventional tails.
4. Fuel sprayed into the throat of a carburetor evaporates, a process that consumes a substantial amount of heat. This heat is taken from the air passing through the throat and lowers air temperature there substantially. This is the same reason that your wet skin feels cold after climbing out of a swimming pool; body heat is used to evaporate the water. Also, adiabatic cooling is caused by expansion of air in the throat.
5. There are two prevalent and contradictory schools of thought. The more popular claims that it is a nautical term meaning [navigational] reckoning relative to an object dead in the water. Another claims that the expression was originally deduced reckoning, which became foreshortened to d'ed or dead reckoning.
6. Wingover, which is roughly similar to a portion of a lazy eight. The maximum bank angle achieved during the maneuver is typically between 45 and 90 degrees.
7. (d) Although rare, jet stream slivers can plunge to the surface of the Earth and sandblast the area with high-velocity wind. This phenomenon can last from less than a minute to several minutes.
8. (d) The complete ground-to-air visual code is shown in Chapter 6 of the Aeronautical Information Manual.
9. (c) The most northerly is Svalbard Airport, which is on a Norwegian island due north of mainland Norway. At 78 degrees 14 minutes N, it is only 706 nm from the true North Pole.
10. False. According to FAR 91.205, manifold pressure gauges are required only for "altitude engines," which are those equipped with turbo- or superchargers.
11. True. At least one compass manufacturer, the Airpath Instrument Company, does this to reduce compass errors caused by magnetic dip. The amount of dip offset of a specific compass can be determined by observing the extent to which a compass card is tilted during straight-and-level flight.
12. True. The most famous were the Le Rhone, Gnome, and Bentley rotary-type radial engines, which were used to power many World War I airplanes. The torque and gyroscopic effects of the large rotating masses of these engines made aircraft control difficult.