Convergency and conv angles
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Convergency and conv angles
Hi there. I have a question that need some explanation.
The following 3 positions are given:
A) 0238N 17832E
B) 0317N 17615W
C) 0249S 17905W
Q1 - What is ch lat B - C?
Q2 - What is d long A - B?
Q3 - . A, B and C represent islands forming the HARRY ISLANDS.
A group of tourists is chartering a plane to take them to THE WESTERN HARRY ISLAND. To which of the islands would you take them?
What is the formula for finding change of latitude (Q1) and what are they looking for in Q2? Answers should be given in degrees and minutes.
My book says Convergency = Change of Longitude x Sine Latitude, but I don´t even know where to start :-/
The following 3 positions are given:
A) 0238N 17832E
B) 0317N 17615W
C) 0249S 17905W
Q1 - What is ch lat B - C?
Q2 - What is d long A - B?
Q3 - . A, B and C represent islands forming the HARRY ISLANDS.
A group of tourists is chartering a plane to take them to THE WESTERN HARRY ISLAND. To which of the islands would you take them?
What is the formula for finding change of latitude (Q1) and what are they looking for in Q2? Answers should be given in degrees and minutes.
My book says Convergency = Change of Longitude x Sine Latitude, but I don´t even know where to start :-/
The following 3 positions are given:
A) 0238N 17832E
B) 0317N 17615W
C) 0249S 17905W
Q1 - What is ch lat B - C?
What is the formula for finding change of latitude (Q1)
A) 0238N 17832E
B) 0317N 17615W
C) 0249S 17905W
Q1 - What is ch lat B - C?
What is the formula for finding change of latitude (Q1)
Q2 - What is d long A - B?
what are they looking for in Q2? Answers should be given in degrees and minutes.
what are they looking for in Q2? Answers should be given in degrees and minutes.
Q3 - . A, B and C represent islands forming the HARRY ISLANDS.
A group of tourists is chartering a plane to take them to THE WESTERN HARRY ISLAND. To which of the islands would you take them?
A group of tourists is chartering a plane to take them to THE WESTERN HARRY ISLAND. To which of the islands would you take them?
Last edited by keith williams; 28th Dec 2013 at 16:21. Reason: Brain Fade
short flights long nights
I'm really worried. I fly aircraft around the world, have been for 30!years, and I don't even understand the question, let alone the answer.
I'm really worried. I fly aircraft around the world, have been for 30!years, and I don't even understand the question, let alone the answer.
Its all about the 180 meridian.
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If you understood the question you wouldn't need to fly your aircraft around the world to get from Harry A to Harry C.
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gf- I'm afraid it is another 'PPRune puzzle' - DD appears to be a CPL-IR yet does not know sem to know what happens to longitude at 180E/W. That is the 'point' of the question, which is a very basic one.
Makes you wonder......................perhaps they don't teach Nav any more for the CPL?
Makes you wonder......................perhaps they don't teach Nav any more for the CPL?
BOAC, sadly no longer do they teach the PRINCIPLES of navigation. Even if we never actually used Mercator Sailings in daily aviation, there was a reason why we were forced to master the theory. Some navies and coast guards share a similar attitude and no longer teach celestial to skippers and navigators. Such stuff is seen as unnecessary now that we have GPS even in our mobile phones.
It is interesting to watch how Gen X and Y can usually make the FMC sit up and beg, but when it behaves badly because of either finger trouble or a glitch they don't pick up errors that should be immediately obvious.
Good on the OP for his/her interest in the subject.
It is interesting to watch how Gen X and Y can usually make the FMC sit up and beg, but when it behaves badly because of either finger trouble or a glitch they don't pick up errors that should be immediately obvious.
Good on the OP for his/her interest in the subject.
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"I'm really worried. I fly aircraft around the world, have been for 30!years, and I don't even understand the question, let alone the answer."
After 42 years in pro flying this one had me flummoxed!
So, in an attempt to get the big picture on this, I sourced a large orange and a felt-tip pen and prepared to draw in the points and the proposed route.
And then I thought, "sod it, life's too short" and put the pen away, peeled the orange and ate it and put the peel on top of the central heating boiler to dry it off so's it would be ready for firelighting duty.
Q. Am I taking life too seriously by recycling the peel as bio-mass?
After 42 years in pro flying this one had me flummoxed!
So, in an attempt to get the big picture on this, I sourced a large orange and a felt-tip pen and prepared to draw in the points and the proposed route.
And then I thought, "sod it, life's too short" and put the pen away, peeled the orange and ate it and put the peel on top of the central heating boiler to dry it off so's it would be ready for firelighting duty.
Q. Am I taking life too seriously by recycling the peel as bio-mass?
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Ah! The magic of Mercator’s Sailings. Once learned never forgotten.
Those formulas forever etched into one’s brain:
DLong/DMP = Tan Track & DLat sec Track = Distance
Learn those little beauties and with a set of Norris Tables and you can solve most navigation calculations.
Those formulas forever etched into one’s brain:
DLong/DMP = Tan Track & DLat sec Track = Distance
Learn those little beauties and with a set of Norris Tables and you can solve most navigation calculations.