Cloud as reference point
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Cloud as reference point
During a climb, since the nose is pitch up, chances are we will not be able to see the land to select a reference point, but can use clouds as reference point to help to fly straight.
My question is, if the cloud is moving (due to wind), wouldn't this cause you "chase" the cloud, therefore not flying stragith?
My question is, if the cloud is moving (due to wind), wouldn't this cause you "chase" the cloud, therefore not flying stragith?
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also, cloud banks/bases don't always form to a straight horizon.
So if you are using this as an indicator of horizon or setting attitude in a climb you may inadvertantly establish a bank.
As PilotDAR says, DI and AH are your friends..... and VSI and ASI.....and turn and slip.....compass.....
So if you are using this as an indicator of horizon or setting attitude in a climb you may inadvertantly establish a bank.
As PilotDAR says, DI and AH are your friends..... and VSI and ASI.....and turn and slip.....compass.....
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While the nose might be straight up, you can usually see plenty of land through your peripheral vision and side windows, while still looking ahead, to be able to get a good indication of your attitude.
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Shun
Back in the early days of flying when there was very poor attitude reference and nav instruments, pilots used to climb up through a solid over cast and once on top carve a circle in the flat cloud tops to use as a reference point for a spin descent after a clear air exercise.
Really being situational aware is important ie if your using a nice block of cumulus is the cloud coming straight at you? are you flying towards it in a headwind? or is the wind moving the cloud across your path?
Ok it might not be the most precise method but I must admit to using clouds to take a rest from the instruments.
Very important is flying amongst CBs where you will use the edge of the CB as a reference point work your way around and through weather.
So its ok if you are situationally aware
Pace
Back in the early days of flying when there was very poor attitude reference and nav instruments, pilots used to climb up through a solid over cast and once on top carve a circle in the flat cloud tops to use as a reference point for a spin descent after a clear air exercise.
Really being situational aware is important ie if your using a nice block of cumulus is the cloud coming straight at you? are you flying towards it in a headwind? or is the wind moving the cloud across your path?
Ok it might not be the most precise method but I must admit to using clouds to take a rest from the instruments.
Very important is flying amongst CBs where you will use the edge of the CB as a reference point work your way around and through weather.
So its ok if you are situationally aware
Pace
if the cloud is moving (due to wind)
and lower the nose evey 500ft
Whopity, I am aware that there are two schools of thought about clearing the airspace in a climb, lower the nose or weave.
My view is, lowering the nose is simpler and more comfortable and allows for a good view ahead and each side. I will concede it doesn't clear right below the aircraft nose. To take the arguement to an extreme we do not weave the nose in the cruise we maintain a good lookout, so lowering the nose is similar to a momentary period of cruise flight.
To weave something like a cessna or piper with side by side seating, sufficiently to get a similar view involves a substantial movement of the nose left and right and subsequent rolling of the aircraft, and passengers may find it uncomfortable.
I would also argue that the climb is not maintained due to the loss of roc whilst banked, or certainly not enough to make an appreciable difference.
I will admit in something like a chipmunk or tiger moth, with tandem seating weaving may be preferable but I would suggest pick the method best suited to the aircraft type.
My view is, lowering the nose is simpler and more comfortable and allows for a good view ahead and each side. I will concede it doesn't clear right below the aircraft nose. To take the arguement to an extreme we do not weave the nose in the cruise we maintain a good lookout, so lowering the nose is similar to a momentary period of cruise flight.
To weave something like a cessna or piper with side by side seating, sufficiently to get a similar view involves a substantial movement of the nose left and right and subsequent rolling of the aircraft, and passengers may find it uncomfortable.
I would also argue that the climb is not maintained due to the loss of roc whilst banked, or certainly not enough to make an appreciable difference.
I will admit in something like a chipmunk or tiger moth, with tandem seating weaving may be preferable but I would suggest pick the method best suited to the aircraft type.
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There is nothing wrong with using cloud as a reference point; just don't use it as your sole reference point! You can't fly accurately on a single instrument either so it follows that you do need to apply some common sense.
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Whopity
When you pick a line or track to fly to any point you will I presume offset for drift so your heading maybe 20 degrees left or right.
The poor old cloud cannot do that : )
Fly to the edge of the cloud and your trajectory would be a curve! Unless you were in a direct head or tailwind.
Also remember your speed could be 10 times the wind speed or cloud speed!
Pace
When you pick a line or track to fly to any point you will I presume offset for drift so your heading maybe 20 degrees left or right.
The poor old cloud cannot do that : )
Fly to the edge of the cloud and your trajectory would be a curve! Unless you were in a direct head or tailwind.
Also remember your speed could be 10 times the wind speed or cloud speed!
Pace
Last edited by Pace; 21st Sep 2011 at 13:53.
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"Fly to the edge of the cloud and your trajectory would be a curve! Unless you were in a direct head or tailwind."
Pace, if you fly relative to a cloud, the wind is out of the equation. Put another way: neither cloud or plane cares which way the earth is blowing.
Pace, if you fly relative to a cloud, the wind is out of the equation. Put another way: neither cloud or plane cares which way the earth is blowing.
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Pace, if you fly relative to a cloud, the wind is out of the equation. Put another way: neither cloud or plane cares which way the earth is blowing
Huv
Sorry if I have misunderstood but I was under the impression that the cloud was being used as a marker over a point on the ground.
Obviously if the cloud is moving at a fair rate of kts by the time you get there presuming it is someway off the cloud will no longer be over its initial ground location.
If you use the cloud and you are travelling West East with the winds and cloud movement North to South you would offset for its original position.
If you maintained that offset to compensate for the winds by the time you got near the cloud it would be way south of its original fix and way south of you.
If you flew to the cloud edge you would be way south of the original position and your track over the ground curved.
Pace
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Pace,
Aiming at the cloud you will fly a straight line, just not the one you want unless you have offset for drift then picked your cloud reference.
Looking at the initial post, shum is using a cloud instead of a ground ref point, it is actually using a ground ref point that will cause you to fly a curve as you will drift and have to adjust heading to maintain it, if you set your correct heading for drift this will normally be minimal, but a cloud could actually be a better reference or that reason, remembering of course that, unless at the same altitude the cloud could have very different drift from yourself.
On the weaving/lowering nose, IMHO there is actually LESS discomfort weaving - you only use 15 degrees bank which DOES keep the climb going (in most ac), and if you are not climbing on a set track then just alternate direction of turn each 1,000' rather than turn off and back on. I have had some very stomach churning pitch down and back lookouts done to me (usually on the pitch back up)
Aiming at the cloud you will fly a straight line, just not the one you want unless you have offset for drift then picked your cloud reference.
Looking at the initial post, shum is using a cloud instead of a ground ref point, it is actually using a ground ref point that will cause you to fly a curve as you will drift and have to adjust heading to maintain it, if you set your correct heading for drift this will normally be minimal, but a cloud could actually be a better reference or that reason, remembering of course that, unless at the same altitude the cloud could have very different drift from yourself.
On the weaving/lowering nose, IMHO there is actually LESS discomfort weaving - you only use 15 degrees bank which DOES keep the climb going (in most ac), and if you are not climbing on a set track then just alternate direction of turn each 1,000' rather than turn off and back on. I have had some very stomach churning pitch down and back lookouts done to me (usually on the pitch back up)
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simply look ahead and to the side of the cowling for a reference point ahead ... if it doesnt move then either will the aircraft
attitude should be set with external references and confirmed with instruments
forget about weaving around .... every 1000ft or so lower the nose to get a good look ahead, it should be a gentle lowering of the nose of the nose just enough to look ahead - so gentle your pax would not even notice ... it only takes a second or two ... and wont really affect your climb perfroamnce
Looking at the initial post, shum is using a cloud instead of a ground ref point, it is actually using a ground ref point that will cause you to fly a curve as you will drift and have to adjust heading to maintain it
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I would not totally agree with how you have worded this statement -
heading = track + drift
you need to choose a drift compensated heading that will ensure the aircraft tracks directly to a ground point - choosing one well ahead and keeping it fixed in the window will ensure you fly an accurate track which is generally what we care about - this will also ensures accurate heading maintainence ...
not sure I agree with using clouds as heading references !!
attitude should be set with external references and confirmed with instruments
forget about weaving around .... every 1000ft or so lower the nose to get a good look ahead, it should be a gentle lowering of the nose of the nose just enough to look ahead - so gentle your pax would not even notice ... it only takes a second or two ... and wont really affect your climb perfroamnce
Looking at the initial post, shum is using a cloud instead of a ground ref point, it is actually using a ground ref point that will cause you to fly a curve as you will drift and have to adjust heading to maintain it
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I would not totally agree with how you have worded this statement -
heading = track + drift
you need to choose a drift compensated heading that will ensure the aircraft tracks directly to a ground point - choosing one well ahead and keeping it fixed in the window will ensure you fly an accurate track which is generally what we care about - this will also ensures accurate heading maintainence ...
not sure I agree with using clouds as heading references !!
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Talking realistically when will you use a cloud as a referance? Usually when you are up amongst the clouds with limited views of the ground below.
Good VFR days with extensive views of the ground ahead and you will probably pick a small hill or a power station or town/village on track.
Up amongst the clouds you will be using conventional nav aids so the cloud fixing will probably be because you are tired of instrument/nav flying and decide to fly visually admiring the cloud scenes.
Realistically if you go off track flying to clouds you will soon go back on track using the navaids.
The other reason will be picking your way through weather and avoiding large CBs or for that fact even lumpy stuff like towering cumulus etc.
It is then a matter of picking the right areas to visually head to while reading the tops and bases of the clouds in front as well as whats likely to lie beyond.
In this second scenarion you will be all over the shop so will still rely on navaids to get back on track when the weather has been cleared.
Pace
Good VFR days with extensive views of the ground ahead and you will probably pick a small hill or a power station or town/village on track.
Up amongst the clouds you will be using conventional nav aids so the cloud fixing will probably be because you are tired of instrument/nav flying and decide to fly visually admiring the cloud scenes.
Realistically if you go off track flying to clouds you will soon go back on track using the navaids.
The other reason will be picking your way through weather and avoiding large CBs or for that fact even lumpy stuff like towering cumulus etc.
It is then a matter of picking the right areas to visually head to while reading the tops and bases of the clouds in front as well as whats likely to lie beyond.
In this second scenarion you will be all over the shop so will still rely on navaids to get back on track when the weather has been cleared.
Pace
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Bingofuel suggests that passengers may be made uncomfortable if you weave to maintain viz; they'll be even more uncomfortable if you hit another aircraft.
Seems to me there are two questions here. Climbing out of an airfield, yes, lower the nose to check you are on runway heading, and do this several times. If your climb rate is truly nose up and your performance like in my supercub, remember that in Britain they have curious ways of joining overhead!
As for climbing enroute, weaving is much better for notifying other aircraft of your existence.
As for using clouds for reference, the only one that's guaranteed to stay in one place is the lenticular - unless of course the wind changes.....
Otherwise, by the time you dive back down through the hole, if your GPS has gone up the Swanee, you may find yourself out over the North Sea.....in which case best to radio Aberdeen and ask for help please.
Seems to me there are two questions here. Climbing out of an airfield, yes, lower the nose to check you are on runway heading, and do this several times. If your climb rate is truly nose up and your performance like in my supercub, remember that in Britain they have curious ways of joining overhead!
As for climbing enroute, weaving is much better for notifying other aircraft of your existence.
As for using clouds for reference, the only one that's guaranteed to stay in one place is the lenticular - unless of course the wind changes.....
Otherwise, by the time you dive back down through the hole, if your GPS has gone up the Swanee, you may find yourself out over the North Sea.....in which case best to radio Aberdeen and ask for help please.
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I was always taught lower the nose periodically for two reasons:
1) Viz
2) Cooling - especially in a long climb.
Surely weaving around the place would have a deterimental effect on the climb performance?
1) Viz
2) Cooling - especially in a long climb.
Surely weaving around the place would have a deterimental effect on the climb performance?
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lowering the nose does reduce ROC .... but its pretty insignificant in the grand scheme of things ... remember you are only lowering for a few seconds to look ahead - it might mean your average ROC is 695ft instead of 700ft over a few thousand feet climb
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cloud - no thanks
I went through this excercise 23 years ago -when learning to fly glider - winch take-off. After approx. 80 I flew with chief instructor of our club and he recognised that immediatelly "what are you going to do when there are no clouds?". So I started looking sideways...