Following the SOAS project, we tested each sonic in a zero-wind enclosure within the EOL temperature chamber, measuring wind component offsets and sonic temperature errors over the nominal range -30 C to 55 C. The procedure is to warm the chamber up to 55 C and then slowly decrease the temperature linearly to -30 C, followed by slowly increasing the temperature back to 55 C. The zero-wind enclosure holds two sonic heads on their sides (with the v-axis vertical) and electronics, one above the other and separated with a horizontal layer of rigid blue foam. On the cool-down cycle, the atmosphere around the top sonic is unstably stratified (cold enclosure lid above warmer air) and that around the bottom sonic is stably stratified (cold enclosure bottom below warmer air). The opposite is true during the warm-up cycle. Both the wind component data and the sonic temperature data have significantly less variance when the air is stably stratified, and thus we use data from the bottom sonic during the cool-down cycle and data from the upper sonic during the warm-up cycle.
The following table shows wind component offsets as okay if the u and v offsets are less than +/- 4 cm/s and the w offsets less than +/- 2 cm/s. If the zero wind offset exceeds these thresholds, the table lists the temperature range of the over-limit offset and the largest amplitude of the offset. The plots of offsets versus temperature can then be examined to determine the exact nature of the offset.
The 8th column relates to the following project, METCRAX, in October 2013. The operating temperature range for night-time warm-air intrusions into the crater is on the order of -10 to +20 C. The last column notes whether or not the sonic is suitable for that temperature range.
10/4/13, twh: Added columns 9-13 for post-project EOL zero-wind tests
SN | Location | EOL Cal | CSI Cal | u | v | w | METCRAX? | CSI recal | EOL cal | u | v | w |
---|---|---|---|---|---|---|---|---|---|---|---|---|
0536 | FLR 3m | 8/1/13 | 6/27/12 | ok | ok | ok | OK |
| 12/03b/13 | ok | ok | 35 - 53 C |
0537 | NEAR 3m | 8/1/13 | 6/21/12 | ok | ok | ok | OK |
| 11/26b/12 | ok | ok | ok |
0538 | NEAR 10m | 7/25/13 | 10/17/12 | 32 - 49 C | 46 - 49 C | 44 - 46 V | OK |
| 12/06/13 | ok | 40 - 47 C | 43 - 47 C |
0539 | FAR 3m | 8/2/13 | 6/20/12 | ok | ok | ok | OK |
| 12/09/13 | ok | ok | ok |
0540 | Rim 15m |
| 2013 recal |
|
|
| OK | 6/13/13 | 12/02b/13 | ok | ok | ok |
0671 | Rim 25m | 8/3/13 | 6/28/12 | ok | ok | ok | OK |
| 11/26/12 | ok | ok | ok |
0672 | NEAR 30m | 7/26/13 | 10/10/12 | 35 - 49 C | 36 - 49 C | ok | OK |
| 12/03/13 | ok | ok | ok |
0673 | RIM 35m | 7/25/13 | 7/18/12 | ok | 25 - 44 C | 20 - 50 C | OK |
| 11/25/13 | ok | ok | 41 - 46 C |
0674 | NEAR 40m | 7/29/13 | 8/13/12 | ok | ok | ok | OK |
| 11/22/13 | ok | ok | ok |
0677 | SSW4 | 8/2/13 | 6/17/12 | ok | 16 - 30 C | ok | Requires | 8/20/13 | 11/25/13 | ok | ok | ok |
0720 | NEAR 45m | 7/31/13 | 1/31/11 | ok | ok | ok | OK |
| 11/26b/13 | ok | ok | ok |
0738 | not used | 8/1/13 | 5/12/10 | 17 - 25 C | 10 - 45 C | 26 - 42 C | Returned to |
| NA |
|
|
|
0739 | RIM 5m | 8/1/13 | 8/18/10 | 46 - 55 C | ok | 48 - 55 C | OK |
| 12/04/13 | 43 - 55 C | 51 - 53 C | 51 - 53 C |
0740 | NEAR 50m | 7/31/13 | 8/28/12 | ok | ok | 26 - 36 C | OK |
| 12/05/13 | 39 - 43 C | ok | ok |
0800 | RIM 40m | 7/29/13 | 6/19/12 | ok | 10 - 35 C | 17 - 53 C | Requires | 8/19/13 | 12/03/13 | ok | ok | ok |
0853 | NEAR 35m | 8/2/13 | 6/21/12 | ok | ok | ok | OK |
| 12/03b/13 | ok | ok | ok |
0855 | spare | 8/3/13 | 9/12/12 | -13 - 1 C | ok | 44 - 49 C | Marginally |
|
|
|
|
|
0856 | NEAR 20m |
| 2013 recal |
|
|
| OK | 6/12/13 | 12/04/13 | ok | 25 - 53 C | ok |
1117 | NEAR 25m |
| 2013 recal |
|
|
| OK | 6/11/13 | 11/26/13 | ok | ok | ok |
1119 | spare | 7/26/13 | 8/9/12 | ok | 49-53 C | 1 - 44 C | Marginally |
|
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|
|
|
1120 | RIM 20m |
| 2013 recall |
|
|
| OK | 6/12/13 | 12/05/13 | ok | 20 - 38 C | ok |
1121 | SSW2 | 7/26/13 | 12/8/11 | -14 - 24 C | -14 - 44C | -15 - 49 C | Requires | 9/5/13 | 11/22/13 | ok | ok | ok |
1122 | NEAR 15m | 7/26/13 | 12/8/11 | 28 - 53 C | 49 - 53 C | 48-53 C | OK |
| 12/06/13 | 47 - 53 C | ok | 43 - 53 C |
1123 | RIM 30m |
| 2013 recal |
|
|
| OK | 6/13/13 | 12/02b/13 | 38 - 43 C | ok | ok |
1124 | RIM 10m | 8/2/13 | 7/19/12 | ok | ok | ok | OK |
| 12/09/13 | ok | ok | 39 - 45 C |
1124b | 12/10/13 | ok | ok | 37 - 46 C | ||||||||
1244 | spare | 7/30/13 |
| -25 - 49 C | 11 - 30 C | 18 - 42 C | Requires |
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