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pump up
25th May 2008, 05:21
I'm sure this has been covered before, but after trawling through pages of posts I haven't found anything. So could someone please advise me of a good formula for Point of No Return with regard to jet operations?

Angels 60
25th May 2008, 05:34
Departure to destination Fuel needed in lbs/gallons =
Assuming no wind, Half way point minus a safety margin= Turn around point where you now have enough fuel to get home.

As life isn't this simple...calculating your winds along the route, so that you know which point that you can return to say fight headwinds that used to be tailwinds back to original distination.

Other factors are your limits on how bad the destination's weather or situation is before you would turn around. Also you might consider your ability to turn back to your destination, conditions there..

Point of No return for planes is a term used for when you commited to your destination at a certain point where returning you won't have enough fuel.

Some ops don't have a point of no return but rather 'Island Fuel' for those ops in the S. Pacific for instance. That might be flying to this island, then having say another 2 hours of fuel when you get there for weather, or someone put a plane wheels up on the one runway.

There are alot of factors here...Interesting stories of Ferry pilots in C152s going to Hawaii and turning around after like 8 hours and flying back to the states...winds had changed.

I am by no means an expert in this area..I would look at how the military conducts polar ops down in Antartica...and overwater Ferry pilots in small planes..

Hope this helps..

BOAC
25th May 2008, 07:48
All you need - from Google (http://www.airsafaris.com.au/general_info/pnrcp.htm)