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The reference mark height for configuration 3 was not measured agl, but was measured to be 15.2 cm below the reference mark for configuration 2 or 1.76m-0.15m = 1.61 m. (BUT the height of the configuration 3 reference mark on the profile tower was later measured to be either 1.505m or 1.53m!) The heights of the downwind array sonic booms above the reference mark were measured to be
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1b | 3.263 |
5b | 3.262 |
5t | 4.260 |
7b | 3.261 |
7t | 4.264 |
11b | 3.262 |
11t | 4.264 |
for a mean sonic heights of 3.26m+1.61m+0.05m = 4.92 m and 5.92 m agl. The heights of the upwind sonics appear to be 3.254m+0.05m+1.61m = 4.91 m agl.
The profile sonic (?) heights were measured on Aug 3 :
| 8/3/08 boom hts | +1.61m +0.05m | +1.51m +0.05m | +1.53m +0.05m |
|---|---|---|---|---|
8m | 6.468m | 8.13m | 8.03m | 8.05m |
7m | 5.544m | 7.20m | 7.10m | 7.12m |
5.8m | 4.256m | 5.92m | 5.82m | 5.84m |
4.8m | 3.316m | 4.98m | 4.88m | 4.90m |
3.3m | 2.110m | 3.77m | 3.66m | 3.68m |
1.5m | -0.026m | 1.63m | 1.53m | 1.55m |
There are several statements about the heights of the reference marks in this logbook entry. It is stated that the profile reference mark for configuration 3 = 1.505 m agl, but also that it is 0.027 m "above top of 1.55m sonic" (boom?), implying a height of 1.55m+0.027m-0.05m = 1.53 m agl. Then it says the reference mark for configuration 4 is 0.040 m above the reference mark for configuration 3, which could be 1.65m, 1.55m or 1.57m agl.
This logbook entry also measures the sonic and SHT heights wrt the 1.55m sonic boom. Note that these heights were not changed between configurations 3 and 4, and are consistent within 1cm of the last column of the preceding table.
nominal ht | sonic* | +1.55m | SHT* | +1.55m-0.42m |
|---|---|---|---|---|
1.5m | 0.0 | 1.55m | 0.376 | 1.51m |
3m | 2.140m | 3.69m | 2.542 | 3.67m |
4m | 3.352m | 4.90m | 3.749 | 4.88m |
5.5m | 4.286m | 5.84m | 4.710 | 5.84m |
7m | 5.582m | 7.13m | 5.886 | 7.02 |
8m | 6.508m | 8.06m | 6.878 | 8.01 |
- measured wrt the 1.5m sonic boom (at 1.50m agl )