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DenisPC9
12th Dec 2008, 00:29
I was talking to an ex Qantas Super Connie pilot several years ago and he described how they navigated across the Pacific. I have forgotten most of the details but essentially they followed isogonals/winds or something. As a result their flightpath wasn't great circle but rather a wandering path to achieve the best fuel burn rate.

Does anyone have any more (and accurate) details of what I am trying to describe? :ugh:

John Hill
12th Dec 2008, 00:44
I am sure they would have done that if they knew where the winds were! There was an quite extensive, still is, meteorological observing network in the South Pacific complete with wind finding radars at major islands.

One of my tasks in the late 60's, early 70's while based in the Pacific was to receive (on Morse code) the 'grid winds'. This was a table of numbers that when transcribed to a sheet of paper in the proper format could be directly read as a weather map including isobars and wind strengths and directions, I think we did sea level and 20,000'

Did the Super Connies carry a radio operator? No doubt he would have copied the same.

Feather #3
12th Dec 2008, 03:40
DenisPC9,

I suspect you are describing "pressure pattern flying", but I'm not entirely sure that it was used trans-Pac in those days. Arguably, the legs we too short for full effect?

G'day ;)

Brian Abraham
12th Dec 2008, 03:42
This may be the sort of thing you're after Dennis http://williams.best.vwh.net/smxgigpdf/smx2001c.pdf Also your library may have a copy of D.C.T. Bennett's "The Complete Air Navigator" (it's an old, old book and was THE TEXTBOOK in it's day) which gives a bit of an insight into the days of long range piston engine navigation.

Basically you could say the aim was to make the flight in the minimum amount of time. The great circle, although minimum distance between departure and destination, is rarely the minimum distance in air miles because of the influence of wind. So you need to optimise the use of any tailwind available and minimise the influence of any headwind. For example, if the direct path involved tracking through the centre of a high pressure cell and through the centre of a low in the southern hemisphere when flying west you would track north of the high and south of the low and so have tailwinds the whole way. Tracking east would be north of the low and south of the high, thus the track in both cases would be a "S" shape. Naturally many other considerations would need to be made, LORAN coverage, ability to get an astro fix (overcast), terrain (LSALT), icing, thunderstorms etc etc The aircraft may have changed from wood and canvas to aluminium in those days, but its fair to say the crews were of tempered steel, compared to the ease we enjoy nowadays.

DenisPC9
12th Dec 2008, 04:12
Thanks for that description Brian and for Feather #3 that was the term that was used, thanks.

Fris B. Fairing
12th Dec 2008, 04:49
Did the Super Connies carry a radio operator?

Yes they did.

Here are their names ... well some of them anyway.

QANTAS CONSTELLATION CREW (http://www.adastron.com/lockheed/constellation/conniecrew.htm)

Rgds