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Thread: Time zone conversions, 1943?

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    Default Time zone conversions, 1943?

    I have a time zone dilemma I wish to clarify, if possible. Takeoff times in logbooks by two airmen – a navigator and a wireless op – differ for eight flights they made in the same Liberator trasiting from the UK to India in March and April 1943 (seven transit hops and one air test). Total flight times, day and night, agree 100%.

    I noticed “G.M.T.” written at the top of the takeoff column in the W/op's logbook. Perhaps he was recording his takeoff times in Greenwich time from point of departure at Lyneham all the way to arriving at Salbani, India (159 Sqn).

    For now, I would like to know what, in March/April 1943, the time zone differences would have been between G.M.T. and each destination:

    Start: RAF Lyneham (should be the same in both logbooks, but there’s a 2 hr difference…indicating an error)

    First destination: Gibraltar

    Second destination: LG 224 (Cairo West)

    Third destination: Habbaniya, Iraq

    Fourth destination: Bahrein Island

    Fifth destination: Karachi, India

    Sixth destination: Allahabad, India

    Seventh destination: Salbani, India (65 or so miles west of Calcutta).

    Hopefully one of our experts can set me straight here.

    Thanks,

    Matt

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    Matt, Some info - based on Air Routes India booklets.

    Third destination:
    Habbaniya, Iraq (3 hours ahead of GMT)

    Fourth destination:
    Bahrein Island (4 hours ahead of GMT)
    Sunrise on Mar 15 - 0248 GMT, Sunset at 1447 GMT
    Sunrise on Apr 1 - 0230 GMT, Sunset at 1455 GMT


    India had one time zone, but the vast size of it meant different sunrise / sunset timings were communicated to aircrew. So here you go..
    Fifth destination:
    Karachi, India (IST 6.5 hours ahead of GMT)
    Sunrise on Mar 21- 0806 IST, Sunset at 2013 IST
    Sunrise on Apr 1 - 0754 IST, Sunset at 2018 IST

    Sixth destination
    : Allahabad, India (6.5 hours ahead of GMT)
    Sunrise on Mar 21- 0707 IST, Sunset at 1914 IST
    Sunrise on Apr 1 - 0655 IST, Sunset at 1919 IST

    Seventh destination: Salbani, India (6.5 hours ahead of GMT)
    Sunrise on Mar 21- 0641 IST, Sunset at 1848 IST
    Sunrise on Apr 1 - 0630 IST, Sunset at 1852 IST

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    Late reply, Jagan.

    Thanks, and I'll need to study your numbers just a little more closely when I can. There were some takeoff time recording errors made in one or both of the logbooks, as you will see in my summary taken from the two logbooks, but figuring out the accurate takeoff times in some cases will be a roll of the dice.

    Generally speaking, though, it does seem that the navigator was recording local time...sort of, kind of...and the wireless op I guess was keeping things in G.M.T...kind of, sort of.

    Below are the comparisons between the two airmen's numbers for the flights in question. You will see obvious error/inconsistency. Why didn't these guys realize at the time that I would want precision all these years later?

    Navigator: 29.3.42, 00.00 takeoff time. Base to Gibraltar 1.00 day, 6.25 night
    W/op: 28.3.42 (date discrepancy vs the nav), 02.00 takeoff time. Lyneham to Gibraltar 1.00 day 6.25 night
    02 hr difference in takeoff times.
    The local time datum for the base (Lyneham) would have been G.M.T., and I would have expected both logbooks to give the same takeoff time.

    Nav: 31.3 20.00 takeoff time. Gibraltar to L.G. 224 (Egypt) 2.00 day, 8.50 night
    W/op: 31.3 20.00 takeoff time. Gibraltar to Middle East 2.00 day, 8.50 night
    00.00 difference in takeoff times.
    Jan 2017: 1 hr time zone difference between GMT and Gibraltar, so it seems that one of the two logbooks is in error.

    Nav: 2.4.43, 05.00 takeoff time. L.G. 224 (Egypt) to Habbania (Iraq) 4.20 day
    W/op: 2.4.43, 09.00 takeoff time. Middle East to Habbaniya 4.20 day
    04 hr difference in takeoff times.
    Jan 2017: 2 hr time zone difference between GMT and Cairo, Egypt

    Nav: 3.4.43, 07.00 takeoff time. Habbaniya to Bahrein Is. 3.25 day
    W/op: 3.4.43, 12.00 takeoff time. Habbaniya to Bahrein Is. 3.25 day
    05 hr difference in takeoff times.
    Per Jagan: wartime 3 hr time zone difference between GMT and Habbania, Iraq

    Nav: 4.4.43, 05.50 takeoff time. Bahrein Is. to Karachi (India) 4.35 day
    W/op: 4.4.43, 09.00 takeoff time. Bahrein Is. to Karachi 4.35 day
    03 hr 10 min difference in takeoff times.
    Per Jagan: wartime 4 hr time zone difference between GMT and Bahrein

    Nav: 12.4.43, 09.30 takeoff time. Air Test 0.50 day (at Karachi, India)
    W/op: 12.4.43, 11.00 takeoff time. Air Test 0.50 day
    01 hr 30 min difference in takeoff times, so there seems to be an error here, probably in one of the logbooks.
    Per Jagan: wartime 6 hr 30 min time zone difference between GMT and Karachi, India

    Nav: 13.4.43, 09.30 takeoff time. Karachi to Allahabad (India) 4.35 day
    W/op: 13.4.43, 03.00 takeoff time. Karachi to Allahabad 4.35 day
    06 hr 30 min difference in takeoff times.
    Per Jagan: wartime 6 hr 30 min time zone difference between GMT and Allahabad, India

    Nav: 14.4.43, 09.00 Allahabad to Salbani (India) 2.10 day
    W/op:14.4.43, 02.25 Allahabad to Salbani 2.10 day
    06 hr 35 min difference in takeoff times.
    Per Jagan: wartime 6 hr 30 min time zone difference between GMT and Allahabad, India

    Navigator’s total flight times for these eight flights: 22.55 day, 15.15 night
    W/op’s total flight times for these eight flights: 22.55 day 15.15 night

    I should add that I'm editing/revising the manuscript of the wireless op for a book project. I thought I was done editing his description of the transit flights...and then I found the family of the navigator in the last week, and they sent me his logbook scan. So I think I'll have to go back and revise some of the writing, slightly, in regard to takeoff times and taking into consideration sunset/sunrise data, too. Because I've found that navigators' logbooks tended to be more accurate than other airmen's logbooks, I'll probably lean towards going with the navigator's times...though I still have to correlate with sunrise and sunset, where I can. Picky, picky, picky!

    Thanks, Jagan, once again.

    Cheers,

    Matt

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    Hi Matt

    I'll try and find the spreadsheet that I put together a while ago to show in diagrammatic form how 'UK' and 'German' times compared with each other and with GMT throughout the war.

    But from some of your initial comments, namely:

    [QUOTE=Matt Poole;123040]
    I noticed “G.M.T.” written at the top of the takeoff column in the W/op's logbook. Perhaps he was recording his takeoff times in Greenwich time from point of departure at Lyneham all the way to arriving at Salbani, India (159 Sqn).
    Start: RAF Lyneham (should be the same in both logbooks, but there’s a 2 hr difference…indicating an error)


    ... my first "wonder" is whether, at that date, the UK was on Double British Summer Time, 2 hrs ahead of GMT, for its 'local' time and the W/Op was recording GMT times while the other chap was using 'local' UK time?

    Just a thought.

    Ian

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    DBST started at 0100 GMT on 4 April 1943 (http://www.miketodd.net/other/bsttable.htm), thus on 29 March the time difference between GMT and local time (BST) in the UK was one hour).

    Brian

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    Thanks, Ian and Brian.

    I'm more convinced than ever that I should just go with the navigator's times, assuming they are local...and I still have to cross-reference to sunrise/sunset data for the first two flights, from the UK to Gibraltar, and then Gibraltar to Egypt, when some of the flying was at night.

    Ian, I think I'll save you the trouble of looking for your spreadsheet -- which was a very kind offer.

    Both logbooks are in agreement for the men's many flights together...with the odd five minute difference in a time here and there (not unusual). It's really only for the transit flights from the UK to India where there are differences in takeoff times. I've looked at a fair number of logbooks for Liberator serial number info that I compile, and these two books are pretty darn good. It's just a shame I'm running into a quandary now...but, honestly, it's pretty minor stuff.

    Thanks for your assistance, and you too, Jagan.

    Cheers,

    Matt

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    Forgive me if you have already gone down this route, Matt, but is there not an ORB you can cross-reference the times for the Lyneham departure?

    Brian

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    Excellent question, Brian. No, my brain had misfired on an RAF Lyneham or perhaps specifically a 1445 Flight ORB which might give the details. I've just emailed a researcher, Colin Burningham, who in the past had extensively investigated the ferrying of aircraft to the Far East. We'll see...with luck he will have the details. If not, I'll consider ordering from Kew.

    Cheers,

    Matt

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    Hello Matt

    Glad to see you are still at it!

    There are odd exceptions to the rule, if times recorded are taken from signal transmissions etc. (If I've understood the Air Ministry Signal Manual) - I've posted a WW 2 King's Regs para and then found the quoted Air Publication A.P. 1083, page images here (click on images for higher res.) ...

    http://www.rafcommands.com/forum/sho...-(GMT-BST-etc)

    Best Regards, Mark
    Last edited by Mark Hood; 11th January 2017 at 19:16.

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    Hi, Mark, and thanks for your info.

    Regarding the takeoff time of a Liberator in late March '43, I heard back from Colin Burningham, but the RAF Lyneham records don't help. He's going to snoop around further for the 44 Group ORB, but it's a long shot. After, oh, nearly 74 years some things are hard to pin down!

    Cheers,

    Matt

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