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Old 2nd Jan 2018, 16:54
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Concours77
 
Join Date: Nov 2016
Location: Lakeside
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Originally Posted by G0ULI
It is standard practice to estimate instrument readings from the faint indentations left in the dial face at the moment of impact. The wing contact with the railroad embankment was unlikely to have been severe enough to produce such a mark. We are left to conclude that the second impact with the ground that detatched the nose section was the one that produced the witness marks used to estimate the aircraft attitude at that point.

It is very tempting to try and read between the lines and second guess the investigators, especially when an element of doubt has been raised about certain aspects of the report. I prefer to believe the report should be read without trying to put a modern interpretation on the wording. It is clear the investigators at the time knew what they were doing.

What I find incredible is the accuracy with which cables in the control runs were expected to be assembled and installed. Cable runs of hundreds of inches were expected to terminated and fastened to tolerances measured in hundredths of an inch or better than one part in ten thousand. The aircraft was originally built with the precision of a Swiss watch, an incredible technological achievement. Despite the disruption, the investigators were still able to draw meaningful conclusions from the wreckage.
Thanks Gouli, a patient and thoughtful message for all.

I have been considering the quality of construction myself. Impressive. The long cable runs terminating in four inches of a connection devised by daVinci, threads.

To be accurate, it is not the cables that adjust to tension, they are finite in length, and subject only to variations in temperature, in Lockclad, even the temperature deviation is mitigated by the locking aluminum sheath around the stainless stranded cable.

The 4.2 inch stainless threaded couplers and brass junction blocks were the culprits.

When considering the precision in cabling, one wonders why the cables were not simply thimbled, and held in place by safetied bolts.

Tension could be adjusted with deflection in the cable, without the need for “safety wire”.
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