Originally Posted by
MickG0105
You're new here so, I'll be nice. It's not speculation, it's estimation.
And the maths is simple, it's year 7 level. We have two different answers (not three) because we have two different estimates of the distance between the prop strikes. I think megan now sees that her original estimate was on the low side because her reference measurement was on the high side; that means that you can discard the original estimate of 1586 rpm. So now you have one estimate that is within 6.7% of 2000 rpm; that's not bad given the method of estimation, moreso when we can see that the prop speed is retarding at about 4% per completed rotation as it chewed its way along the roof.
It is worth noting that 300mm between the roof cladding ridges is the largest distance likely and based on that we get an average left prop rotation of around 1866 rpm. That speed is in the green arc. If the ridges are closer than 300mm then the estimated rpm goes up, not down.
Ummm 2000 rpm WAS given 1st then revised to 1586. It WAS not given as an estimate as it WAS ginen as 2000rpm. Funny thing is you cant even agree on the size of the corrugations in the roof sheeting. The only thing that is true is the prop rotational speed WAS between 0 and 2050 rpm. And btw with your estimate it is 3 different speeds.
You clearly dont understand how the egine in question works and the difference of that 25%ish means to the outcome of this investigation.