Trivia Testers : First Blood

Figure 1

First Blood
The first use of an airplane for intentional civil violence (pardon the oxymoron) was

  1. in 1964. on May 7, an intruder shot the pilot of the Pacific Airlines Fairchild F-27, which then crashed near Doublin, CA, killing all aboard.
  2. in 1955. On November 1st, a United Airlines DC-6B exploded in flight and crashed near Longmont Colorado. Investigators later discovered that someone had placed a bomb aboard the airplane in order to collect on an insurance policy taken out on a passenger (which in this case was that person’s mother).
  3. on November 12, 1926. Three bombs were dropped on a farmhouse in Williamson County, Illinois. In this case, it was a feud between two rival bands of bootleggers, the Shelton gang, and the Birger gang. Regrettably, none detonated.
  4. on November 1, 1911. An Etrich Taube monoplane was used by Italy to drop bombs in Turkey.

Answer: C. Sadly, choices A and B are not fiction. Lt. Gavotti’s action from choice D doesn’t count as a civil action because at the time, Italy and Turkey were at war. This was however one of the first (if not the first) dropping of bombs from a military airplane. Going even further back of course, man’s inhumanity to man had taken to the skies in balloons over a century earlier. According to the Smithsonian’s “Book of Flight”, the first recorded use of balloons in warfare was by France, at the Battle of Fleurus, in Belgium, in 1794.

The Original Genius?
Who was the first person in history to write about flying in any mechanical or truly scientific sense?

  1. Leonardo da Vinci (1452-1519)
  2. Roger Bacon (1214 – 1294 )
  3. Abbas ibn Firnas of Islamic Spain, in the 800’s A.D
  4. the Greek, Archytas of Tarentum, ca. 428-350 B.C.
  5. no one really knows

Answer: E. We know that Leonardo da Vinci was a genius unlike almost any other known to history. This great Italian painter, sculptor, architect, engineer, musician, and natural philosopher carefully studied the flight of birds and established some fundamental principles, but his preternatural insights did not include even the more intuitive precursors to fluid mechanics, atmospheric physics, or aeronautical engineering. Furthermore, so much written knowledge has been lost to the multiple evils of war, ignorance, and the ravages of time that even credentialed historians don’t really know for certain what unsung intellects of even greater proportions may have discovered–perhaps before there were means to document it, and before they vanished from human memory and record. What is known is that the English philosopher, Franciscan monk, and scientist Roger Bacon was interested in the biological and physical sciences. Many discoveries have been credited to him, and he foresaw the extensive use of mechanical cars, boats, and planes. In his book “De mirabili potestate artis et naturae” (“The Wonderful Power of Art and Nature”) written ca. 1250 A.D. (but which was not published until much later), he describes a lighter-than-air flying boat, with wings driven by a hand-turned crank mechanism. Bacon followed the maxim “Cease to be ruled by dogmas and authorities; look at the world!” His central goal, it seems, was to prove that during the age of alchemy in which he lived, the “inferiority and indignity of magical power, compared with nature and science.” He speculated that, since hot air rose, it could be contained, such that a vehicle could float in the air and move about without touching the ground. (Francesco de Lana, 1631 – 1687, the subject of an earlier Trivia Tester, may in fact have gotten this idea from Roger Bacon.)

Abu’l Qasim Abbas ibn Firnas of Islamic Spain supposedly invented, constructed, and tested a flying machine in about 875 A.D. It has been claimed that Roger Bacon learned of flying machines in fact from Arabic references to Ibn Firnas’ machine. (If so, it would antedate Bacon by 500 years and da Vinci by about some 700 years.) ibn Firnas, who died in the year 888, came to Cordoba to teach music, but became interested in the mechanics of flight. He reportedly constructed a glider and attempted (successfully or otherwise) to fly. Of additional interest but totally irrelevant, a mechanic by the name of Charley Furnas became the world’s first airplane passenger (and one of few to fly with both Wilbur and Orville Wright) on May 14, 1908.

One of the first devices to successfully employ the principles essential to rocket flight was a wooden bird. The writings of Aulus Gellius, a Roman, tell a story of a Greek named Archytas who lived in the city of Tarentum, now a part of southern Italy. Somewhere around the year 400 B.C., Archytas mystified and amused the citizens of Tarentum by flying a pigeon made of wood. Escaping steam propelled the bird suspended on wires. The pigeon used the action-reaction principle, which was not stated as a scientific law until the 17th century. About three hundred years after the pigeon, another Greek, Hero of Alexandria, invented a similar rocket-like device called an aeolipile. It, too, used steam as a propulsive gas.

And finally, one must consider what discoveries there may very well have been further to the East. Ancient China, credited with the kite as early as the Fifth Century BC, as well as the rocket before the time of Roger Bacon, may have synthesized these two inventions somehow, although historical evidence has not thus far revealed any quantitative understanding.

In level flight, all air is propelled downward, and it must exactly equal the weight of the airplane.

Getting Pushy!
Your average 172, at normal cruise speed, pushes about how much air downward?

  1. Actually it is more meaningful to speak of a volume of air displaced rearward, rather than downward. Depending upon propeller design and installation, the general ballpark figure for engines of that size would be a static thrust of (very roughly) about 200 Kg. Since air at standard temperature has a mass of approximately one and a quarter kilograms per cubic meter–we’re talking mass here now, not pressure–that equates to about 160 cubic meters per second of air blasted backwards, each second.
  2. an amount equal to about five times its own weight every second
  3. As mentioned in choice B, most of the air is of course directed rearward. However there is a downward component which also equals the weight of the airplane. It is dependent on angle of attack, but it is time-independent.

Answer: C. The other verbiage is mostly chaff. Bulls-eye if you guessed the right answer. It is indeed true at least in a very rough sense that a propeller (one of perfect design) might achieve four pounds of thrust for each available horsepower, but wings keep us up by pushing air down. That Cessna will be pushing about five times its own weight of air down, each second. Air at standard temperature “weighs” (really, it’s mass and not weight) about 1.25 ounces per cubic foot or also, coincidentally, about 1.25 Kg per cubic meter. (The more precise numbers are about 1.22 and 1.29, respectively.) If our Skyhawk weighs one ton, that would be about 4200 cubic meters of air every second. Visualized as a cube of air, that would be a box that’s a bit over 16 meters on a side (or not quite 53 feet) every second!