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All Models - No Thermals at all? (And Other Questions)

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Thank you very much everyone (especially B21 for that fabulous explantion) or your help!

- So basically, approximately 7,000ft (plus a bit extra for confidence) is sensible for a 30NM glide

- Wind is always good - However I did not quite understand from what direction? I've always followed the rule that headwinds are more useful but I may be wrong! As a rule of thumb, what direction would you say the wind should be relative to the Aircraft?

- And also, how do I set the McCready value? In the manual it says that the McCready ring is un-useable in this add-on.

Cheers and kind regards,

Jackbiggrin.gif

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Not easy to explain.

First, headwind makes you slower above ground and reduces your glide angle.

Tailwind makes you faster and your LD bigger.

If you fly in the mountains, the wind towards a mountain is good. Keep on the side of rising air (as in the graphic from Ian)

Wind "leans" your thermals. So if you fly against the wind you will always fall back while circling in a thermal

With wind on the nose you will not come that far as with wind from behind.

So you see, wind is not always good.

You can set the McCready value in the C4 wich is way better than manually on the analogue vario.

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Right so a slight tailwind is better then, thanks for your explanation (maybe I've been hindering myself with a 20 knot headwind?).

And I will attempt to set the McCready value later tonight!

Also, I am currently Flying around Tamworth Australia - There are some good hills (not really mountains as such) around Tamworth, which should help if I have wind blowing into them from my direction (what I mean is, the wind is blowing against the hill in the same direction that my nose is pointing) - Correct?

Finally, what Cable Length would I need for around 7000 AGL? I'm currently using 65,000ft of Cable.

Jackbiggrin.gif

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Finally, what Cable Length would I need for around 7000 AGL? I'm currently using 65,000ft of Cable.

Jack

As Ian said, around 2000ft is your usual. With a few airfields in the UK you can get a max of 3000ft Winch Launches. With WinchX I find that setting your altimeter to the Field i.e QFE 0ft (zero) and WinchX on 3000mtrs then looking at your altimeter, release it manually at 2000ft. You then have the joy of looking and finding the thermals or ridge lift to increase your altitude.

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So I can glide 30NM using lets say... A 2,500ft Winch Launch?

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Yeah 7000ft winch launch is highly unrealistic. I get around 1100ft on my homebase.

So I can glide 30NM using lets say... A 2,500ft Winch Launch?

You could even do with a 1000 ft winch launch.

Regarding ridge lift. I think you still didn't understand it. If the wind blowes against a mountain, you fly along the mountain in the rising air. So you can fly foreward while getting altitude. It doesn't matter where your nose points to.

For example. You are on an airfield with a ridge east of you. Your destination is in the north. If you have west wind you can fly along the ridge and gain altitude. No matter if you fly to the north or to the south.

Here is an example how it could look:

Bests Joachim

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I understand Ridge Lift yessmile.gif .

Also, how do I know what to set the McCready and LD Values to on the C4? I've read the manual to no avail and google search brings me nothing.

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You must set the assumed average climb of the next lift in the McCready setting.

If you had only 2.5 meters/second over the last few thermals you can assume, the next one will have around 2.5 meters/second, too. So you must set 2.5. If you expect 3 meters, set 3. The higher the Value is, the faster is your speed to fly.

You cannot change the LD reading of the C4. The reading is calculated with your current groundspeed and sinkrate. So with headwind your LD reading will be way below 40 and with tailwind above 40 (in dead air)

If you have more sink, the LD reading decreases, if you have less sink it increases. If you have climb it goes to 99.

The McCready is explained in the C4 Manual.

Bests Joachim

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Right we're getting there.

I just managed a 15NM glide from a 2,550ft Winch Cable!

There are some nice hilly areas near Tamworth and Quiridi (where I started from).

I managed to not loose much altitude at all, I just crashed into the mountainside because my speed dropped from 50 knots to 37 due to FSX's stupid wind shifting issues.

Apart from that all good!

Will try a few more glides!

Also, what should I set the righthard adjsutable L/D setting to?

and why does the McCready reading on the left always say 0.0?

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I just managed a 15NM glide from a 2,550ft Winch Cable!

Set a cable lenght of 3000-4000ft, this will give you launch altitudes around 1000 until 1500 ft, depending on wind and skils.

Do you know how to take off on winch? I mean how to do it right?

due to FSX's stupid wind shifting issues.

As I said, set only ONE wind layer and drag it higher as you will climb. Then You don't have any windshifting issues

Also, what should I set the righthard adjsutable L/D setting to?

Let it at it is ;-) You can set it if you plane gets worse due to moskitos on the wings or something

and why does the McCready reading on the left always say 0.0?

Shouldn't be. It should show the average climb of the last thermal.

Cheers Joachim

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Okay gotcha.

I think am I doing the Winch correctly, but can you please tell me the correct procedure?

Also, regardless of what the wind settings are, I'll always get wind shifting (its a pure FSX issue).

Is 4000ft Cable really realistic? Someone said about 2000-3000ft is the usual.

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Also, what should I set the righthard adjsutable L/D setting to?

and why does the McCready reading on the left always say 0.0?

I'm assuming you've got the SDI C4 user manual... each cursor setting is described in there. On the L/D cursor setting, the bottom row of the C4 displays two numbers, e.g. "41 43". The left number (41) is the current *achieved* glide ratio, and right number (43) is the still-air glide ratio *programmed* into the SDI C4 which it is using in the calculation of your arrival height. At this stage, there is no good reason for you to change the programmed value (43 is accurate for the Discus). You would change it in flight if you have bugs on the wings or you left the wheel dolly on (ok I'm not serious with that one) and you think the C4 should be adjusted to be more conservative.

"The McCready on the left" - Of the two numbers displayed (e.g. "2.1 3.0"), the left one is the positive thermalling climb rate achieved so far, and the right number is the McCready setting. The right knob allows you to change the McCready setting on the right ( I think you get this bit now). The reason you are seeing 0.0, as in "0.0 3.0" is a bit subtle... the C4 operates in two modes - thermalling and cruise - the 'vario/stf' switch is *actually* switching the C4 between its cruise (stf) and climb (vario) modes. As it happens in cruise mode the vario needle and sound displays STF, and in thermalling mode it displays Total Energy Vario, hence the label on the vario/STF switch (taken from a real glider). The 'averaging thermalling rate achieved' is the climb rate achieved across the whole time the C4 has been in thermalling (i.e. 'vario') mode. The C4 *assumes* you would be switching between cruise and climb modes manually every time you enter and leave a thermal, so the 'avg. climb' is an accurate reading of the true climb rate in the thermal. *But*, if you *leave* the C4 in vario mode during both climbs and glides, the 'avg. climb' will quite quickly average out to zero, so this is what you will see every time you enter that cursor position. Because it is a bit of a pain in the ass to click the panel each time you enter/leave a thermal (and also in a real glider), most pilots don't bother and hence the 'avg. climb' reading is ignored by the pilot when he's setting the McCready.

B21

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No it is only an issue if you have various wind layers. If you have only one layer you can't have any shifting.

Nevertheless, you shouldn't fly that slow near mountains. Add safety speed!

Winchlaunch has to be done as following: (short)

Once the plane lifts off you do not much only pull a bit. After getting safety altitude of 200ft slowly begin to pull the stick to get a good climb rate. Climb with around 60kts (set this into the winchprogram also) Sometimes it is easily possible to pull the stick all the way back. Once you've reached the point, where the nose begins to go down slowly release elevator imput and wait for the automatic release. manually releare 3 times after this

If you got some cross wind hold the nose INTO the wind to not be blowen away and help the winchdriver to get the rope in front of the winch.

Doing winch launchs like this, you'll get around 1000-1500ft altitude out of 3000-4000ft rope lenght.

Note rope lenght is NOT the final altitude!

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As I said, set only ONE wind layer and drag it higher as you will climb. Then You don't have any windshifting issues

Also when setting one wind layer in advanced weather setting, set gusts to zero and turbulence to none. That will give you stable wind.

Bert

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Hey,

Thanks everyone for replying - My Glider knowledge has vastly improved!

@Joachim - How can I get 15,000ft altitude from a 4000ft cable? Wouldn't that be impossible as the cable would have to be elastic!

I will try just setting one layer and see if the problem persists.

Also, am I correct in thinking that to get the best ridge lift (as per B21's picture) You need to Fly slightly offset from the peak on the side from which the wind is blowing?

I'll see if I can make Tamworth from a 5,000ft cable!

Cheers,

Jack

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@Joachim - How can I get 15,000ft altitude from a 4000ft cable? Wouldn't that be impossible as the cable would have to be elastic!

Yes, they are elastic. Winchcables are steelwires, they are elastic. But not THIS WAY :D Sorry this was a typo and I corrected it to 1500ft...

Also, am I correct in thinking that to get the best ridge lift (as per B21's picture) You need to Fly slightly offset from the peak on the side from which the wind is blowing?

Not always, every mountain is different. You must find the best lift yourself every time.

Bests Joachim

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Will do a flight now then.

Not expecting to get to Tamworth, but I'll just see how far I can get.

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Wooooooo!

I made it!laugh.gif

With a 5,000ft Winch Cable and a 15-20 Knot Tailwind (yes I only applied one layer and no gusting... No Wind Shifting!).

I even made it with only lift from 2 Thermals no and Ridge Lift whatsoever (was too high really for the Tamworth Hills to effect me).

Here is a picture of the Flight Status of my victorious attempt:

ToTamworthProg.jpg

I even managed to circuit all the way around runway 36 at Tamworth so I could land into the wind instead of with it (to allow much better stopping).

I used a tiny bit of help from the C4, and loads from the Winter TEC and the Petal Display.

Next job is to really get immersed into the C4 - I'm still a bit unsure on some of its modes and functions.

Jackbiggrin.gif

P.S: Flight distance is actually about 35-40 Miles

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Congrats, but to be honest, what you've done is no real sailplane flight. It is like the last part of a flight, -the final glide.

Sry for destroing your happiness here :(

You didn't use one thermal or something. You lost altitude all the time. Next thing should be taking off, with no special destination, search, find and use thermals.

Searching, easy somewhere under the CumulusX! clouds

finding, a bit more difficult, because you must search a bit under the cloud, the wind leans the thermals and so on

using, even more difficult, stay in the lift while doing continous circles with 50-55 knots and a bank of around 30 degree. You must practise to use thermals to be successfull on long overland flights.

With a 5,000ft Winch Cable and...

What I see on your log is a more than 5000ft take off altitude. Again, it has nothing to do with rope lenght. A normal take off or release altitude is at 1000 - 1500ft.

Cheers Joachim

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Hello there,

I can confirm that I did sucessfully use one thermal (there was hardly any).

I wanted to try this without too much lift - Using thermals would've made the flight easier and given me more lift and height.

Now that I know I can glide properly I will try Ridge Flying more often (I'm 100% okay using Thermals).

Qiridi is about 1,500ft Elevation so that would explain the high altitude at the start of the flight.

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Hmm, but the red line in your barogramm shows me sinking from the beginning, and the brown line showes me your ground profile. So I see a take off altitude of over 5000ft and from there only gliding straight down. Same in the map view no circle at all.

Tamworth is at around 1500ft, too, but your take off alt was 7000ft.

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Qiridi is slightly higher than Tamworth.

Anyway, the Thermal used was discovered late on in the Flight.

by now means was this a thermal or ridge flight - I simply wanted to go from A to B.

This was more of a test to see if I got the Glide Speed correct.

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Ahh ok, then I missunderstood the goal of this flight.

speed should be always as high as possible and as low as needed. ;-)

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Okay thanks for your help as always another flight (Ridge Flying) will be done later tonight.

Now, please tell me if I have my understanding of the C4 functions correct (I need some help here):

- NAV: Not too sure what this does

- GOTO: Something to do with the final gldie and some sort of glide path?

- DISTANCE: The distance to a set goal (do I have to input this manually?)

- WIND: Displays wind, also Headwind inputs should be negative and vice versa for tailwinds (again do I manually enter this?)

- A.H: Arrival Height. Not really sure what to do here

- VOL: Volume

- L/D: Right reading is manually inputted L/D, and left reading is current L/D (I should aim for right L/D value)

- W/L: Wing Loading. I know what this is but how do I find out what it "is for the day"

- HEIGHT: QFE or QNH entry for your location. Which is better and what should I do?

- BAT: Battery

- TEMP: Shows OAT

- INFO: Shows various information (when changed using right rotary) such as Turn/Time/etc) - When I use the right rotary it only switches between two modes though

Thank you very much for reading and I hope you can answer,

Jackbiggrin.gif

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