about 0.2 of a second of arc. This was applied to Arnold's sighting.
The "Arnold-saw-airplanes" faction maintained that since Arnold said
that the objects were 45 to 50 feet long they would have had to be
much closer than he had estimated or he couldn't even have seen them
at all. Since they were much closer than he estimated, Arnold's timed
speed was all wrong and instead of going 1,700 miles per hour the
objects were traveling at a speed closer to 400 miles per hour, the
speed of a jet. There was no reason to believe they weren't jets. The
jets appeared to have a skipping motion because Arnold had looked at
them through layers of warm and cold air, like heat waves coming from
a hot pavement that cause an object to shimmer.

The other side didn't buy this idea at all. They based their
argument on the fact that Arnold knew where the objects were when he
timed them.

After all, he was an old mountain pilot and was as familiar with the
area around the Cascade Mountains as he was with his own living room.
To cinch this point the fact that the objects had passed _behind_ a
mountain peak was brought up. This positively established the
distance the objects were from Arnold and confirmed his calculated
1,700-miles-per-hour speed. Besides, no airplane can weave in and out
between mountain peaks in the short time that Arnold was watching
them. The visual acuity factor only strengthened the "Arnold-saw-a-
flying-saucer" faction's theory that what he'd seen was a spaceship.
If he could see the objects 20 to 25 miles away, they must have been
about 210 feet long instead of the poorly estimated 45 to 50 feet.

In 1947 this was a fantastic story, but now it is just another UFO
report marked "Unknown." It is typical in that if the facts are