00:01
In this problem, we're given a graph, and we're told that this is part of determining structural integrity of an aircraft based on its age.
00:13
So we're told that this gives us the fleet damage rate.
00:22
I owe a typical fleet for a commercial air flight.
00:26
And t is measured in years.
00:30
And what we're looking for is where f is decreasing.
00:37
So that would be the time period when the fleet damage rate is dropping as problems are found and corrected.
00:45
We're looking for when f is constant.
00:47
So when there's a few structural problems, there's not a whole lot of change.
00:53
Everything is pretty constant there.
00:55
And where f is increasing.
00:57
So after the time mentioned in part b, where we're looking at the increase in structural defects, primarily from metal fatigue.
01:10
So this isn't too hard if we understand what we're looking for...