I Presentation of the Dehavilland Comet crash due to metal fatigue

AI Thread Summary
The discussion focuses on a presentation about the Dehavilland Comet crash attributed to metal fatigue, specifically analyzing the fuselage's cycle count before failure using Paris law equations. The user, Louis, encounters a significant discrepancy in calculated cycles, obtaining 1.272*10^33 instead of the expected 1272. Forum members suggest that the error likely stems from unit miscalculations or incorrect mathematical operations, particularly with powers of ten. They recommend posting the formula and input values for clearer assistance. The conversation emphasizes the importance of accurate calculations in understanding the crash's causes.
siuolleboss479
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Hi,
I need some help,
I want to do a presentation of the Dehavilland Comet crash due to metal fatigue and want explain what caused this with a Paris law equation.
So I watched this video: https://shorturl.at/xlUp4
The goal is to find the number of cycles that the fuselage went through during its lifetime before it torn off. In my case I find 1.272*10^33 instead of 1272 in the video, how can I explain it? I put the link going to the exact timeline of the video so you can understand what i'm talking about.
Here's the video of me trying to resolve it on the calculator:
Good day,
Louis
 
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Welcome to PF.
siuolleboss479 said:
The goal is to find the number of cycles that the fuselage went through during its lifetime before it torn off. In my case I find 1.272*10^33 instead of 1272 in the video, how can I explain it?
Is it only the 10^33 exponent that is a problem with your calculation?
 
Not many people are going to spend their time trolling through the videos, so you are more likely to get helpful answers if you post the formula (use Latex!) and the input values you used.

But even though I'm not going to sit through the videos, an error that is both enormous and an exact power of ten usually means that you messed up your units or multiplied/divided somewhere when you should have divided/multiplied. Because 30 is equal to six times five, I would be especially suspicious of any input that is raised to the fifth power.
 

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