Further CW inclinometry runs using the 'fixed' TMU inclinometer were made on the 3rd, 4th & 5th (HST) of May :

    Datasets El Dirn     HST     mean leg temperatures   Humidity
                        start      start   middle   end       %
  ( 20020429 90 cw       20:54      3.8      3.7    3.3     100 )
    20020501 90 cw       06:40      0.6      1.2    2.4      40
    20020503 90 cw       05:44      2.9      2.9    3.3     100
    20020504 90 cw '4_1' 19:10      5.0      5.0    5.0     100
    20020504 90 cw '4_2' 22:03      5.0      4.9    4.8     100
    20020505 90 cw '4_3' 00:48      4.8      4.6    4.5     100  
    20020507 90 cw       18:20      5.2      4.9    4.5     100

The temperature data from the fixed TMU inclinometer seem OK again (!?) so data were processed into a track model in the conventional way. The models resulting from the data of May 03/04/05 are compared below with the model from the 29th :

• Justin's 'spikes' are manifest in the colder data of the 03rd, and absent from the warmer data of the 04th/05th, in line with Justin's theory. Unfortunately the temperature variation through the 04th/05th was rather small and all three datasets are 'good'.

• w.r.t the first plot : it's interesting to note that the sizes of the 'spikes' in quadrant 5 are v.similar to those in q1, in keeping with the minimal temperature change during the 3 hours of the data acquisition.

• The formal differences in (F1,F2,F3) between the last of the new data and the reference data of 29 Apr are described by the rms scatters of (0.20", 0.17", 0.20") - which is as close as two datasets ever get !

• . . . as a result of which : no change to the model has been made. The model of 29 April seems valid.

• The recent data would suggest that the 'spikes' appear when the antenna leg temperatures drop below, perhaps, 4degsC, and it'd be nice to add a qualification to the use of the above model, but the 'warm' (~5degC) data of 24th Apr will always provide a counterargument to any selected (lower) cutoff in temperature.

07 May 2002
Data show hint of the first 2 spikes, but one of these certainly diminishes in amplitude by the end (as the temperature falls ?) contrary to expectation. Hmm ?

• Updates have been made to the plots of symmetry and strain gauge data.