OCTG climb gradients in NZ AIP
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OCTG climb gradients in NZ AIP
I'm having a good look through NZ AIP and can't find where the OCTGs for each airfield are listed (as we have in ERSA).
I have found the critical obstacles section in SUP and type A charts from the AIM but neither of these give a figure.
I hope i dont have to use maths to figure them out.
Help please
I have found the critical obstacles section in SUP and type A charts from the AIM but neither of these give a figure.
I hope i dont have to use maths to figure them out.
Help please
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We Kiwi's are a bit slow. Tell us what on earth an OCTG is and we might be able to help.
I read the thread title and thought it would be something about Tauranga!
http://www.aip.net.nz/pdf/GEN_2.2.pdf Does not give a definition of OCTG (in this country at least). Give us a clue mate
I read the thread title and thought it would be something about Tauranga!
http://www.aip.net.nz/pdf/GEN_2.2.pdf Does not give a definition of OCTG (in this country at least). Give us a clue mate
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Obstacle Clear Take-off Gradient.
Basically they have worked out what sort of climb gradient you need to clear obstacles in a surveyed area and noted it down next to the TODA as a percentage.
In the New Zealand AIP, Volume 4, Aerodrome charts you can see in the operational data there are a number of take-off distances listed 1:20 1:40 etc. That is the take-off distance available for a given climb gradient to clear obstacles expressed as a ratio. So some mathematics is involved but towards the front of the AIP there is a table which converts speed and gradient to a percentage so it's not all bad.
Basically they have worked out what sort of climb gradient you need to clear obstacles in a surveyed area and noted it down next to the TODA as a percentage.
In the New Zealand AIP, Volume 4, Aerodrome charts you can see in the operational data there are a number of take-off distances listed 1:20 1:40 etc. That is the take-off distance available for a given climb gradient to clear obstacles expressed as a ratio. So some mathematics is involved but towards the front of the AIP there is a table which converts speed and gradient to a percentage so it's not all bad.
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Yea that's all you're going to get from AIP Vol4.
What you're looking at are a range of safe TO distances available dependent on the climb gradient (1:20 through to 1:62.5) applicable to your Aircraft/Operation.
Go to the Vol2&3 for percentage specific climb gradients on the SIDs at your aerodrome and refer also to Table ENR 1.5-1
Hope this helps
What you're looking at are a range of safe TO distances available dependent on the climb gradient (1:20 through to 1:62.5) applicable to your Aircraft/Operation.
Go to the Vol2&3 for percentage specific climb gradients on the SIDs at your aerodrome and refer also to Table ENR 1.5-1
Hope this helps
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Sometimes done using an inclinometer survey but more generally a typical xyz triplet survey and then worked backwards to give the gradient.
I would have thought anyone with PPL level Nav would be sufficiently comfortable with gradients (1:60 rule, eg) to figure out the basic sums ?
I would have thought anyone with PPL level Nav would be sufficiently comfortable with gradients (1:60 rule, eg) to figure out the basic sums ?
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another to know where to find the information in unfamiliar Pubs.
Absolutely the case. However, if you know the triplet value it is a simple calc to figure the gradient. The other way around can be a bit more torrid unless you have multiple gradients co-incidentally based on the same obstacle.
Absolutely the case. However, if you know the triplet value it is a simple calc to figure the gradient. The other way around can be a bit more torrid unless you have multiple gradients co-incidentally based on the same obstacle.
