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    Re: Wind Velocity from Three Drifts
    From: David Pike
    Date: 2021 Mar 11, 12:28 -0800

    David C you wrote: Can I be bold and suggest that Chichester got the time wrong? 

    David.  I was hoping you or Bill Morris would pick this up.  I was aware of the frequent changes in amounts and dates of Daylight Saving Time in New Zealand between 1927 and 1933 having read the History section at the bottom of this page Daylight Saving Time 1927 in New Zealand .  The conundrum starts in ‘Alone over the Tasman Sea’ where Chichester says that despite aiming for an 06.00 NZ time take-off from Auckland on 28th March, he was shocked to see the dashboard clock reading 6.15 while he was still compass swinging.  Then he remembered he’d set that clock to GMT so he still had ¼ hour to go to 06.00.  I.e it was 18.15 on 27th March GMT.  This means he’d retarded that clock by 11 ½ hrs acknowledging the official time difference. 

    However, in the same chapter, after not leaving the aircraft at Parengarenga Bay while refuelling, he states he finally got airborne again at 11.50 `.  He writes 11.50 on his chart and also 23.50 GMT (the 50 is hard to read and it might be 23.30, but it certainly wasn’t 00.20 as an 11 ½ hr time difference might suggest).  Working backwards from his 0100GMT air position on his chart, the distance corresponds to 70 minutes flying.  I.e. a 23.50 GMT take-off. 

    Therefore, we’re faced with three possibilities.  1.  Chichester was by now using his best navigation watch set to GMT, and he temporarily forgot that New Zealand time was now 11 ½ not 12 hours after this, so he wrote 11.50 when he should have written 11.20 NZ time.  This wouldn’t have affected his navigation.  2.  The second possibility hardly bears thinking about.  If he really did take-off at 11.50 NZ time, he took off at 00.20 GMT; his celestial was out by 30 minutes; and his safe arrival Norfolk Is was entirely down to luck.  3.  The third possibility seems the best explanation.  When he wrote 11.50 on his chart, he was writing what he saw on his dashboard clock, but this was 11.50 PM. I.e 23.00GMT on the 27th. He seems to have done the same taking off from Norfolk Is.  He writes on his chart that he took off at 10.50, but in ‘Alone over the Tasman Sea’ he says he was airborne at 22.50 GMT, or 10.02 (a typo for 10.20) local time.  His dashboard clock would have been reading 10.50, which is what he wrote down.

    So yes, Chichester did get the time right.  It’s just hard to see at first, because wrote down what he read from his dashboard clock not local NZ time.  Some websites simply say he took off at  11.50 and leave it at that.  Phew!  My head hurts.  Dave P

     

     

       
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