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Flying With Wind  Topic is solved

Controlling your aircraft, using the autopilot etc.

Flying With Wind

Postby Matuchkin » Fri Dec 21, 2018 3:41 pm

It's quite apparent that, with real life conditions, simply pointing your aircraft at a certain course (i.e. intercepting a radial or flying RNAV) doesn't cut it - you just won't be going that direction due to wind. However, I (flying the C182S) cannot spot any equipment that will allow to calculate course deviation in flight. I can, of course, do what I always did: do basic vector addition in flight. But this obviously isn't the way that actual pilots deal with wind. Is there a way that I can deal with course deviation in flight, preferably without trigonometry, a calculator, and a lot of frantic scribbling?
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Re: Flying With Wind

Postby Thorsten » Fri Dec 21, 2018 3:58 pm

simply pointing your aircraft at a certain course (i.e. intercepting a radial or flying RNAV) doesn't cut it -


Actually intercepting a VOR radial does cut it - it's not the same as pointing the nose. Maybe you should read some radio navigation theory?

The CDI is what you want to be looking at.
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Re: Flying With Wind

Postby Matuchkin » Fri Dec 21, 2018 4:30 pm

Thorsten wrote in Fri Dec 21, 2018 3:58 pm:
simply pointing your aircraft at a certain course (i.e. intercepting a radial or flying RNAV) doesn't cut it -


Actually intercepting a VOR radial does cut it - it's not the same as pointing the nose. Maybe you should read some radio navigation theory?

The CDI is what you want to be looking at.


Thank you for your information - the only source of information I have on aviation would be this sim, and I am fairly new to the concept of radio navigation. I will certainly read deeper into the matter. In the meantime, I apologize for my ignorance.
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Re: Flying With Wind

Postby Alant » Fri Dec 21, 2018 4:56 pm

The Dalton E6B computer is the standard tool for this. It is a form of rotary slide rule and has been around since the 1930´s. The same job can be done with a ruler and protractor.

Modern electronic calculators and aircraft avionics such as the CDI now do the same job, but pilots are still required to be able to navigate without electronic aids.

Alan
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Re: Flying With Wind

Postby FlugHund » Fri Dec 21, 2018 5:26 pm

Matuchkin wrote in Fri Dec 21, 2018 4:30 pm:[...] - the only source of information I have on aviation would be this sim, and I am fairly new to the concept of radio navigation.


This site helped a lot of simmers to get started with navigation: http://www.navfltsm.addr.com/
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Re: Flying With Wind

Postby dilbert » Sat Dec 22, 2018 10:24 pm

If you're flying the anticipated correct heading for the VOR and the needle begins to drift left or right, you're drifting off course. Alter heading to stop it drifting further;
then note about how much "crab" it's taking. Double the crab angle to get back on the radial; then resume the amount of crab it took to stop the needle. At some point, using this method you'll determine necessary crab to stay on course. For most pilots it becomes second nature. Also, you would probably have a planned initial flight time on leg based on airspeed and winds aloft. The amount of actual flight time on the completed leg compared to that anticipated gives you an indication of how much time to add or subtract for head or tail wind when estimating time to next way point.

I did a number of cross country flights of limited distance 64 years ago in a
J3. No radios and computer was in head. Used the same basic
method, as above; except course was based on line of sight to a distant object, and I had to adjust crab to keep my requisite heading from changing.
Best Regards :)
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Re: Flying With Wind

Postby Matuchkin » Sat Dec 22, 2018 11:12 pm

I understand the crabbing, et al. But I just don't trust the VOR. I can't bring myself to: the thing doesn't have accuracy and after comparing the needle position with my actual position relative to VORs (using the map feature) at a large distance, I believe it's safe to say that these systems lack in long-range precision. I'm not required to keep my plane exactly on the radial, right? Is the point of this system to gradually hone an aircraft into the localizer, rather than to keep it dead-straight on the radial at any distance?

I should also put the chronometers to use for the first time. Never quite paid attention to them as a simple non-pilot, but now that I'm getting deeper into this I should probably start mimicking professionals. Thank you for your help.
Last edited by Johan G on Thu May 30, 2019 6:01 pm, edited 1 time in total.
Reason: No need to quote the entire preceding post. It is right above yours.
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Re: Flying With Wind  

Postby Alant » Sun Dec 23, 2018 12:06 am

The magnetic variation for a VOR station is usually correct when it was first installed. After that it depends upon how recently the beacon was reset. The same with your charts, and with runway numbers (runway number is meant to be be magnetic heading / 10) . They all change in step with magnetic variation over time.

These days we have GPS which we can assume always gives correct true (not magnetic) track.

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Re: Flying With Wind

Postby dilbert » Sun Dec 23, 2018 12:21 am

VORs are quite reliable. However, if the needle (vertical bar) is all the way left or right in the gauge, you won't no how far you're off track-just whether to the left or right.
In that case you temporarily adjust the radial selection until the needle centers, and note what radial you're actually on; then once knowing, note how many degrees you are off from the radial you want to track. If it's more than 30, your best course of action is to keep the needle centered on the current radial and fly to the station (waypoint).
otherwise turn 30 degrees left of original course, if approaching from right; and 30 right if approaching from left; set the radial selection back to the proper (original) one; then fly back to intersect it.

When the needle gets toward center, turn 30 degrees right if intersecting from
right, or 30 degrees left if intersecting from left, so as to resume a proper (original) course; then maintain it by keeping the needle centered. The important thing to remember is that the needle (bar) merely tells whether you are left, right, or on a selected radial.
The miles off course can be a lot if you are far from the station, and little if close-visualize your position as it might be on a map, where radial lines separate the further you get from the station. Hope this helps
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Re: Flying With Wind

Postby Matuchkin » Sun Dec 23, 2018 10:04 pm

Thank you for your help. As someone who is only now trying to find out how this navigation system works, I have to confirm something: they're tracks, in all essence, right? You can't just set whatever radial is closest to you? I see VFR maps outline various radials in a way that makes it seem as though you absolutely have to use these radials. The way SkyVector details the Hawaii airspace makes it seem as though, to travel from Hilo international to Lihue one has to: perform, say, the Paris 4 departure, traveling to fix PARIS through SAPDE; fly radial 082 to Upolu; fly radial 107 to Lanai; use Lanai radial 278 to intercept South Kauai radial 111 at GECKO; do a Lihue approach from fix MORKE.

So if you are on the wrong radial, do you not have to intercept the radial detailed on the actual travel map?

Also, do you use the KAP 140 to keep on a radial? I notice that, if I'm a bit off course, the aircraft (C182S) starts oscillating between both sides of the radial. Is autopilot traditionally used to keep the plane on course, or is this done manually?

My apologies, again, if this is something that I should have known before. Thank you for your help.
Last edited by Johan G on Thu May 30, 2019 6:02 pm, edited 1 time in total.
Reason: No need to quote the entire preceding post. It is right above yours.
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Re: Flying With Wind

Postby Alant » Sun Dec 23, 2018 11:19 pm

If you want to fly a defined approach or departure procedure (STAR/SID) you should capture and follow the radials detailed on the chart.

It takes some practice to be able to fly a VOR manually. ;)

If the aircraft has one, you may be able to use a flight director, which sends autopilot commands to pointers on the HUD or the HDD for the pilot to follow.

An autopilot in VOR mode should work perfectly. It is one of the simpler modes to implement. If it does not please report your problem.

Finally, do not try to capture a VOR radial if you are too close to the station.

The trick when flying VOR manually is to control the heading, not the bank angle.

So if the VOR beam is to your left, look at the compass and turn left a few degees. (dependent upon how large the error). Maintain that new heading and watch the VOR error. If it decreases, all is well. If it increases adjust your heading a few more degrees to the left. As soon as the VOR error starts to reduce you can fly right on a heading that is closer to the VOR radial, but still is on an inteception course.

To continue following the VOR beam keep turning left or right by a small amount, always using the compass as a reference for your heading. You must always keep in your head both the VOR radial and the compass heading that you are currently using.

If you try to follow VOR using just aileron and bank angle you are making things very difficult.

I hope that you can follow this, but think that there must be clearer explantions out there on the Internet.

Alan
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Re: Flying With Wind

Postby dilbert » Mon Dec 24, 2018 11:28 am

The VORs are for Airways, just like roads in the sky; they are also used as specific locations from which to initiate approaches, or to fly to in order to avoid other traffic, when under Air Traffic Control. Therefore, your planned route, when flying under Visual Flight Rules determines the radial you would want to use for the most direct course to the next VOR; whereas, when flying on an Instrument Flight Plan, or any time when flying under Air Traffic Control, you are required to maintain course on an assigned altitude and radial, or fly directly to a VOR, depending on the filed flight plan or in-flight instruction from Air Traffic Control.

In Flight Gear, when you plan and activate a flight using Route Manager, it's path will appear in >Equipment>Map colored in Magenta. Best Regards :)
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Re: Flying With Wind

Postby cptRon » Tue Feb 05, 2019 4:48 pm

Just to add, the VOR, DME, and ADF radio nav simulation in FlightGear is quite reliable. I've used it many times without problem.

There are some slight hitches sometimes, which can be do to the particular aircraft, but also make sure the real world frequencies match with FlightGear data. I have experienced on occasion that a VOR freq in sim was different than what was on the charts. Always use the FlightGear nav data if it differs from the charts. You can find the map with nav aids in sim under Equipment->Map. You may have to select the Data and Navaids boxes and zoom in on an area before seeing the frequencies.
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