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funkster319
03-28-2008, 08:02 AM
Ok we all know the expression "step on the ball" for correcting yaw etc so this is kinda a silly question which has bugged me for ages.

In Spitfires there is NO BALL to step on. We have the Slip/Turn indicator -

I presume that the upper needle is the same thing as the ball?

And if should be kept centred for coord turns etc?

Is the princilple the same i.e If the needle is to the left then lef rudder to correct?

Jambock_Dolfo
03-28-2008, 09:45 AM
One of the pointers is a turn coordinator, the other acts like a slip ball. Cant say which is which from memory.
Try kicking full rudder on level flight and see the instrument response. Should give you the idea.


-dolfo

rnzoli
03-28-2008, 10:47 AM
Example: if upper arrow points left, you step on the left pedal in order to bring it back to the middle. Or more frequently, trim the rudder to the left.

Platypus_1.JaVA
03-28-2008, 10:54 AM
http://forums.ubi.com/images/smilies/351.gif

K_Freddie
03-28-2008, 03:08 PM
The pointer (needle) is usually an indicator of your turn circle time (2 minutes in the horizontal AFAIK), when the ball is centred.

This is a basic guideline, but not the 'TRUTH' http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

buzzsaw1939
03-28-2008, 03:43 PM
I hope your reffering to the game Freddie!.. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

M_Gunz
03-28-2008, 04:14 PM
Originally posted by funkster319:
Ok we all know the expression "step on the ball" for correcting yaw etc so this is kinda a silly question which has bugged me for ages.

In Spitfires there is NO BALL to step on. We have the Slip/Turn indicator -

I presume that the upper needle is the same thing as the ball?

And if should be kept centred for coord turns etc?

Is the princilple the same i.e If the needle is to the left then lef rudder to correct?

Yes. And it's a beotch in the Spit IX's to get used to. Switch off to other planes and you
lose that as well. Best to fly Spit-dedicated for month or more or leave it alone.

Nicholaiovitch
03-28-2008, 04:27 PM
Many of the British types of that era were fitted with this "turn indicator".
As has been pointed out, the top needle shows "slip", and the bottom needle shows "rate of turn".
To complete a co-ordinated "rate 1 turn" (bottom needle indicating No 1), you need to keep the top needle centered (rudder left/trim left- if needle left of centre) and 30deg. bank.
This gives 3deg.per second rate of turn so 2 minutes to turn through 360deg.
A rate 2 turn is harder to fly needing 45deg. bank and gives 6deg.per second.
The Spitfire/Seafire in IL-2 is quite accurate in re-producing these figures at cruise config:-
RPM 2650
Boost 7ins (60% power)
210kts indicated in clean config.
Does that help or have I made the water even muddier?
I guess it shows my age as I learnt to fly on aircraft fitted with this device!
Have fun.
http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

stathem
03-28-2008, 05:22 PM
Originally posted by Nicholaiovitch:
Many of the British types of that era were fitted with this "turn indicator".
As has been pointed out, the top needle shows "slip", and the bottom needle shows "rate of turn".
To complete a co-ordinated "rate 1 turn" (bottom needle indicating No 1), you need to keep the top needle centered (rudder left/trim left- if needle left of centre) and 30deg. bank.
This gives 3deg.per second rate of turn so 2 minutes to turn through 360deg.
A rate 2 turn is harder to fly needing 45deg. bank and gives 6deg.per second.
The Spitfire/Seafire in IL-2 is quite accurate in re-producing these figures at cruise config:-
RPM 2650
Boost 7ins (60% power)
210kts indicated in clean config.
Does that help or have I made the water even muddier?
I guess it shows my age as I learnt to fly on aircraft fitted with this device!
Have fun.
http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

No that's brilliant Nicho, I always wondered what a Rate 1 turn was.

Many thanks.

buzzsaw1939
03-28-2008, 06:17 PM
Your quite right Nicholaiovitch.... http://forums.ubi.com/images/smilies/25.gif

However, in rl your speed and power sttings have no bearing on the turn rate, if your cordinated and smooth, haven't tried it in game, are you saying it matters in game? just curious!

Nicholaiovitch
03-29-2008, 04:45 AM
Originally posted by buzzsaw1939:
Your quite right Nicholaiovitch.... http://forums.ubi.com/images/smilies/25.gif

However, in rl your speed and power sttings have no bearing on the turn rate, if your cordinated and smooth, haven't tried it in game, are you saying it matters in game? just curious!

Sorry Buzz, I did not give you the full picture.
- It is more complex IRL as the problem becomes different with increasing height. reducing IAS and increasing TAS.
- To give you an example, At 30,000 with an indicated IAS of 250Kts, your TAS is around 420kts. This will require 5 minutes to turn through 360deg. at 25-30deg bank (equivalent of an old fashioned Rate One Turn.
- To keep it simple, I flew the profile in IL-2 at an indicated 210kts. in level flight at 2000ft. Since TAS is not a problem at that altitude, the Rate One Turn works well. I only gave the power settings so that others may wish to try the experiment.

Hope that makes it clearer! I have spent quite a lot of time "exploring the flight envelope" particularly in the Seafire as it featured heavily in my offline campaign "Z Force Singapore 1941". I find it very interesting to see how close Oleg has managed to get to RL.

http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

M_Gunz
03-29-2008, 08:45 AM
Funny how I accepted that bank angle set how many G's the plane is turned with and TAS sets
the radius of the turn.

Kettenhunde
03-29-2008, 12:33 PM
Funny how I accepted that bank angle set how many G's the plane is turned with and TAS sets
the radius of the turn.


Bank angle does set the load factor for any turn no matter what the altitude.

TAS will change with altitude but EAS remains constant. That is why EAS is commonly used in aerodynamics to describe aircraft performance.

buzzsaw1939
03-29-2008, 12:47 PM
http://forums.ubi.com/images/smilies/25.gif http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

M_Gunz
03-29-2008, 09:05 PM
Originally posted by Kettenhunde:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Funny how I accepted that bank angle set how many G's the plane is turned with and TAS sets
the radius of the turn.


Bank angle does set the load factor for any turn no matter what the altitude.

TAS will change with altitude but EAS remains constant. That is why EAS is commonly used in aerodynamics to describe aircraft performance. </div></BLOCKQUOTE>

My lift may be by EAS but my inertia is by TAS. Are you sure that turn radius won't change
with changing EAS/TAS relation at different alts and same bank?

buzzsaw1939
03-29-2008, 11:18 PM
maybe it would be easier to understand this turn and bank thing if we put it in a practical application.

I tought my students that it could save your bacon if you flew into a fog bank or cloud.

when turning, your mag compass would have a turning error, (dip), if you can hold the bank needle steady on the 2 minute mark through 60 seconds, you have made a 180 degree turn, no matter what altitude or airspeed your doing.

the less dense air at altitude means more speed, the more speed, the greater the radius.

TX-EcoDragon
03-30-2008, 02:33 AM
Originally posted by buzzsaw1939:
maybe it would be easier to understand this turn and bank thing if we put it in a practical application.

I tought my students that it could save your bacon if you flew into a fog bank or cloud.

when turning, your mag compass would have a turning error, (dip), if you can hold the bank needle steady on the 2 minute mark through 60 seconds, you have made a 180 degree turn, no matter what altitude or airspeed your doing.

the less dense air at altitude means more speed, the more speed, the greater the radius.

Yes, though the bank angle required for that turn rate would be be variable depending on airspeed.

A way to approximate the bank angle required for a 3 degree per second turn rate is to divide KTAS by 10 and add 7 to the result. So at 100 KTAS you would need a 17 degree bank for a standard rate turn, at 300 you would need 37 degrees.


This can be handy in turbulence, when making that 180 degree turn!

Nicholaiovitch
03-30-2008, 03:21 AM
A way to approximate the bank angle required for a 3 degree per second turn rate is to divide KTAS by 10 and add 7 to the result. So at 100 KTAS you would need a 17 degree bank for a standard rate turn, at 300 you would need 37 degrees.

Excellent formula TX. I guess we have all found that with the size of the rate of turn indicator, certainly on the Seafire, it is impossible to use it accurately as Buzz is suggesting IRL, so to convert it into a useable bank angle is just what you need.
All we need now is a practical application in IL-2!
Damage modelling in the Seafire does not seem to include "limited panel" requirement unfortunately, so at night, in low level mist and in what cloud there is available, one tends to use the AH.
We sure have hammered this one!
http://forums.ubi.com/images/smilies/88.gif

Kettenhunde
03-30-2008, 04:27 AM
It's covered.

M_Gunz you understand that EAS does not change with altitude but TAS does correct? Your question is confusing on this point.

It is standard to use TAS for turn radius calculations.

TAS is EAS corrected for density effects.

All the Best,

Crumpp

M_Gunz
03-30-2008, 04:51 AM
I don't see what's so confusing. The relation of TAS to EAS is TAS/EAS and changes with alt,
ie is not constant: at the same EAS and two different alts, TAS is higher at the higher alt
so the relation changes.

Of course I'm more used to IAS than EAS since my panels show IAS.

I see my confusion. When you wrote "aircraft performance" I thought you included turn radius.

Kettenhunde
03-30-2008, 06:01 AM
The relation of TAS to EAS is TAS/EAS and changes with alt,ie is not constant: at the same EAS and two different alts, TAS is higher at the higher alt so the relation changes.

Nobody has said it was constant either. It changes with SMOE.


When you wrote "aircraft performance" I thought you included turn radius.

I see. No I was only talking about Angle of Bank. The fact all aircraft at the same radius and angle of bank will make exactly the same turn is why we can have a standard rate turn in aviation.

All the best,

Crumpp

M_Gunz
03-30-2008, 12:29 PM
Yeah, if I gain SMOE altitude, TAS goes up for same IAS.

buzzsaw1939
03-30-2008, 12:48 PM
Originally posted by TX-EcoDragon:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by buzzsaw1939:
maybe it would be easier to understand this turn and bank thing if we put it in a practical application.

I tought my students that it could save your bacon if you flew into a fog bank or cloud.

when turning, your mag compass would have a turning error, (dip), if you can hold the bank needle steady on the 2 minute mark through 60 seconds, you have made a 180 degree turn, no matter what altitude or airspeed your doing.

the less dense air at altitude means more speed, the more speed, the greater the radius.

Yes, though the bank angle required for that turn rate would be be variable depending on airspeed.

A way to approximate the bank angle required for a 3 degree per second turn rate is to divide KTAS by 10 and add 7 to the result. So at 100 KTAS you would need a 17 degree bank for a standard rate turn, at 300 you would need 37 degrees.


This can be handy in turbulence, when making that 180 degree turn! </div></BLOCKQUOTE>

My old memory wants to argue that point TX, but I think it would be wiser to concede to your more recent experience and knowledge! http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

I never got into or taught more than the basics in those days, even when I got my instrument rateing, I just ask that every one concider that when I speak in here, I comeing from the basics, never had time to study advanced aerodynamics.

Still don't have time! http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

I forgot to mention that I never saw a DG till I had about 30 hr's, then the timed turn seemed kind of irrelevant from then on!

Viper2005_
03-30-2008, 01:47 PM
It's quite surprising how well the simple method put forward by TX-EcoDragon works provided that you keep within a reasonable speed range.

It will overestimate the bank angle required at low speeds, but once you get to about 120-150 knots it is accurate to within 1º.

Above this speed range it will tend to slightly underestimate the bank angle required. It becomes accurate to within 1º again between 390 and 450 knots. Above this speed it rapidly loses accuracy, overestimating bank angle, and therefore should not be used...

Wildnoob
03-30-2008, 03:09 PM
I are having a trouble with this.

I'm trying to set the variometer neutral to level fligth, but are having many trouble and cannot make it. wat I want is set the variometer on 0 to do cruize fligth like EVERY aircraft.

people tell me to adjust the rudder, but some planes don't have rudder trim. so, wat I should do ?

in fact, wat I should do keep the variometer neutral. can't be complex, it's a very basic fligth procedure.I try adjust the rudder trim, but the variometer still stay positive or negative.

please, wat you guys do to set the variometer neutral to hands off fligth ?

buzzsaw1939
03-30-2008, 03:36 PM
Wildnoob...It sounds like your confuseing your rudder with your elevator, it's been said in here that some planes don't have rudder trim, that it's been set to cruise conditions in that particular aircraft.

I'm pretty sure all ac's have elevator trim, (could be wrong), your VSI (vertical speed indicator) or (variometer) will read weather your climbing or desending.

If you have no trim in your chosen AC, you will have to find the cruise speed, or try another AC!

Good luck!

M_Gunz
03-30-2008, 08:33 PM
No rudder trim like in 109 you are supposed to hold the pedals where they need to be.
Galland and other FW pilots joked about Hartmann always walking in circles for a reason.

It is elevator that wildnoob needs to adjust trim on though as well as use the rudder to
coordinate the turn. IL2 is not so easy with twisty stick or cheap tiny close-set pedals.