Well, seeing as I can't watch a long video explaining what someone else thinks time is, I may as well go ahead and post my own thoughts.
First, though, we will need a prop for demonstration purposes. A nice young lady would make a great prop, but we actually need the P-51 in the background. While the aircraft itself makes a nice prop, I actually want to use the prop on the front of the aircraft as my prop. And to add to that, I want to use the tip of one prop on the prop on the prop as my basic prop.
So now, we have a P-51, with a 4 bladed prop. Not knowing the actual size of the 4 bladed prop, let's just give it a diameter of 6 feet.
Now, what I'm mainly interested is just the tip of one blade, and the distance it travels in one revolution, which would be the circumference of a circle with a 6 foot diameter.
6 X 3.1415.... = 18.85 feet.
Now, let's start that bad boy up, and rev that motor up to 3600 RPM. What I'm interested in is RPSeconds, so divide 3600 RPM by 60 seconds, and we have that prop turning at 60 RPS. So now I'm interested in finding out how far the tip of the blade travels in one second.
At 18.85 feet per revolution X 60 RPS = 1131 feet the tip has traveled. This, while the aircraft is stationary. If we put the aircraft into the air, moving at 360 MPH, will we find a change in any of these figures?
At 360 MPH, the aircraft is traveling at 360MPH ÷ 60 minutes = 6 miles a minute.
At 6 MPM, the aircraft is traveling at 6MPM ÷ 60 seconds = 0.1 mile per second.
0.1 mile = 528 feet per second.
So now, we have the tip of the blade moving at 1131 feet in one second, but also moving forward at 528 feet per second. Does that forward movement (speed), affect the tip of the blade and the distance it travels in one second?
Actually, it does. The tip of the blade is not just describing the circumference of a 6 foot circle, it is also describing the distance traveled forward. How? The tip is now describing a corkscrew path thru a distance, much like the threads on a screw.
As the threads on a screw are longer in going around the circumference of the screw shaft than just a ridge that just goes around the shaft flat wise, then the length of travel of the blade tip is longer at 528 FPS than while stationary. And, like the threads on a screw getting coarser, and becoming longer in one circumference when stretched out, so does the corkscrew path of the blade tip as its velocity increase. The faster its velocity, the more distance it covers in one second, and thus lengthens the corkscrew path of the tip.
What does this mean in our discussion of time? While sitting stationary, the blade tip is traveling at 18.85 feet per revolution @ 60RPS = 1131 total feet traveled. Launch that aircraft @ 528 FPS (360 MPH), the blade tip has to travel a longer, corkscrew path in one second. That longer corkscrew path adds the 528 feet traveled to the 1131 feet traveled if just sitting stationary. That is 1131 feet + 528 feet = 1659 total feet of travel. But that 1659 was supposedly done at 60RPS. So, divide 1659 feet by 60 RPS = 27.65 feet per revolution.
Now, that blade tip can only travel at 18.85 Feet normally to make one revolution. But at a velocity of 528 FPS, it has to travel a 27.65 foot path to make one revolution. So, when a stationary tip has traveled 18.85 feet and completed one revolution, the tip a velocity only traveled at 18.85 feet also, but yet has not yet traveled far enough to complete a revolution. Thus, the pilot might think, "Man, on the tarmac I was getting so many RPS, but flying certainly seemed to cut the number of RPS I'm getting. Gee, when I'm flying, it takes longer to get one revolution. Gee, the only explanation is that time has slowed down."
But that's BS. Time hasn't changed at all. What has changed from stationary to moving is the distance over which an action has occurred. The blade tip while stationary could complete a revolution in 18.85 feet of travel. But when moving, the corkscrew path makes a longer distance to travel. The blade tip is moving at the same speed whether stationary or moving. When the blade tip moves 18.85 feet and makes a revolution while stationary, while flying it has moved the same 18.85 feet at the same time, but is only part way thru a longer path to a full revolution.
Has time slowed down? No, only the distance over which an action occurs has been increased because of adding velocity.
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