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Old 21st Dec 2010, 03:15
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A664
 
Join Date: Dec 2007
Location: Germany
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Qbix:
They are providing on request QAR data which I think is sampling at the rate of 1 frame/ sek. Pretty slow to me.

Among other things there are 8 air/grnd sensors, 8 accelerometers, RA, IAS, GS, VS, pitch,N1, etc
The landings look normal. N1 ok, descend rate reducing from 800-900 to 50-100ft/min, speed ok, pitch normal...
You can see from following frames that another A/G sensors change from AIR to GRND. Then there are 8 values of vertical acceleration. At the peak of any of them the values are:
1,63 1,37 0,87 0,68 0,91 1,18 1,21 1,02. As you can see one of them reaches 1,6G and this for the company is hard landing.

Another example at the touchdown: 0,76 1,23 1,73 1,61 1,01 0,60 0,72 1,05
In the QAR systems I know a frame can contain the same parameter multiple times in order to facilitate sampling more than once per second. Therefore, I guess that these 8 values are 8 measurements from 1 accelerometer during 1 second - this would seem like a usual recording rate for vertical acceleration. It might be similar with the A/G sensor(s). However, I'm not familiar with the B737 and don't know if this interpretation is consistent with the form in which the data were presented to you.
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