SFMA Map - Bad Winds?

[Electroman]

Hi All,

I was recently flying on the SFMA map in Lancs towards a field at around 13.5K Level. There was a massive wind pushing me south on the map when I was flying and not sure why as I was below the wind levels. I noticed it on other areas of the map as well pushing me in different directions but this one in particular was noticeable.

I've attached a film clip which catches it at the beginning if you are looking in the gun view and can see the movement.

Can someone confirm if there are some wind layer issues on this map?

Cheers!
Elec1

[Zener]

What I've noticed (on ALL maps) is that the wind layer effects seem opposite in direction.  For example, below 14K the wind is given in direction as 180°.  That should be a wind that moves from dead South to dead North, and indeed the E6B info reflects that... but if you fly on a course of 090° you will see that the "wind" actually pushes you TO the South.  It should push you TO the North. 

I have always thought this effect was due to the "north" pushing winds having a greater effect on the tail of the aircraft than on the nose, thus it makes your course change slightly toward the South. but it fails to "push" on the whole aircraft.  The result is you drift south - into the wind - rather than north, with the wind.

I try to line up (just slightly) on the side opposite the wind when approaching a target, as it becomes visible.  That would be slightly N of target with a wind out of the south (090°).  The "wind" will drift the plane slightly south so you should be right over the target when you need to be.

The effect is very slight, VERY slight, but it's there.

Test it on any map.  Try to fly E or W along a sector line with a N or S wind.  You'll see that you drift into the wind.

[hitech]

The arrow on the map show the direction the wind is traveling.

The e6b show the normal wind from direction.


HiTech

[Zener]

Well I just upped a set of B-17s from a 6K field and climbed up through the first wind layer at 14K.  I was headed 000°.  At 15K, I dove back to 10K and turned to heading 180° and climbed back up through 14K.  Then I got on a sector line headed east at 15K feet and travelled appx. 3/4 of a sector on a course of appx. 088°, simulating a "crab" into the wind of about 2 degrees or so.

Here are the results.

Northbound climbout: 
Climb rate just before hitting the 14K wind layer: 834 fpm
Peak climb rate when hitting the wind layer: 1591 fpm

Southbound climbout:
Climb rate just before hitting the 14K wind layer: 865 fpm
Peak climb rate when hitting the wind layer: 651 fpm

These numbers are consistent with encountering a wind blowing from N to S just as both the wind rose shows AND the E6B shows.  The difference in climb rate from the first climb to the second climb (about 21 mph) is likely the result of having spent some fuel turning and repeating the climb in the opposite direction.

Next on the turn eastbound along a sector line, the wind did indeed blow me off course to the south.  I adjusted course a couple degrees to the north just to make sure I wasn't flying south on purpose.  With the clipboard max at max zoom, over 3/4 of a sector I drifted south by a distance of two sector line widths.  Maybe a mile or so.  This is consistent with the wind rose showing a wind from N to S, and the E6B showing a Left Crosswind component of 20.

So it appears to work fine and be consistent during those quick tests.

However... I have experienced course abnormalities in the past up in the high 20K alts that seemed opposite in direction to what the crosswinds were telling me (E6B).  Most recently I was trying to skirt a dar circle and nearly drifted into it when the wind should have kept me away from it.  Unfortunately I have no data to back that up, it was just one of those things where I expected A, got B, and just compensated to get the job done without thinking in terms of a bug or something.  So all I can say is it appears to work like it's supposed to and the onus is on me to collect some proof if I encounter another one.

[Electroman]

Hey Zener,

If you bring up the winds direction chart (right click map. click winds I think) you will see the chart. The numbers basically as follows:

14K - South - 20 MPH
16K - East - 20 MPH
18K - North - 20 MPH
20K - West - 20 MPH
22K - South East - 30 MPH
24K - North East - 30 MPH
26K - North West - 30 MPH
28K - South West - 30 MPH

Note the above is the direction in which the wind will push you. However, also to note, the full wind deflection only happens 500 feet above the stated altitude. So for example, to get the full South wind at 14K / 20 MPH you need to be at 14.5K up to 15.999K. Then a wind shift will start to occur as you go through the next wind shear level. The same applies for each as you go through it.

This comes in handy when you want to say get the best wind while transiting altitudes based on the direction you want to go. For example, I want to fly up at around 20K and am heading directly south. The wind at 20.5K pushes me at that altitude westward. However, if I jump up to just over 22K where the wind starts to shift and push me Southeast I can find a due south wind of about 15 MPH around 22.3K. This is because the winds are shifting from West to South East. So I can get better altitude while still getting a good tailwind and not having to sacrifice too much. You can see all of this happening when you pull up the E6B from the clipboard and watch the winds change direction (Tail / Head / Left / Right).

That being said, as I originally posted there should be NO WIND below 14K and I was seeing a huge wind deflection happening as I was flying east and there was a massive wind pushing me south. There is supposed to be no wind (0 MPH) below 14K. So hence the original question if there was a problem in the terrain / map settings for wind.

Hope this info helps you or others!

Cheers! 
Elec1

[Zener]

Well I've never tried level flight to test for any "push" below 14k, but I can give it a shot.  I can say that below 14K there is no difference in climb rate no matter which direction you fly, which leads me to believe the 0kt wind indicator on the E6B is accurate.

I'm also aware of the transition altitudes you mention.  That's why I did the above test run at 15K, so I was sure to be out of any transition zone.

Over the course of my next few high-alt missions I'll try to gather some more data and see how it all wrings out.  The anomalies I've encountered don't appear to me to be consistently present.  That's why when I was trying to skirt some dar rings, I set the kind of course I always do yet got different results.  As I said, I wasn't thinking abnormal bug or anything like that at the time, I was just focused on being where I should be and adjusted.  The fact I had to adjust is the anomaly to me, and I'm sure the course was right, leaving only the wind as suspect.

So I want to gather more info and be sure before saying something is "off."  All I have is one or two anecdotal pieces of data which is really worth zip.