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Jatro13th
03-15-2006, 02:53 PM
Hi there, I was just landing and taking off from carriers, and I remembered something that troubled me since I bought PF. I don't know if someone has already mentioned it, so I will ask.

When the plane is sationary on the carrier facing forwards, and the carrier is moving with a speed of 40 Km/h then I get IAS of 40 Km/h. So far so good. The trouble comes when I try to turn the ac around. I apply the brakes, deflect hte rudder in full, and give throttle. The plane starts rotating around its wheel, but when I get almost perpendicular to carrier, the plane stops moving.

My question is: is the force applied to the rudder by a 40 Km/h wind so fearsome that a multi-thousand HP engine cannot overcome it? Was it like that IRL? Something tells me it wasn't, although I may be wrong. But if it wasn't, then this tells a lot about the FM, and maybe it should be checked up on. Here is a schematic:
http://i11.photobucket.com/albums/a172/Jatro13th/Carrier.jpg

P.S. Krashan, please stay out of this until we figure it out, and then say whatever you want http://forums.ubi.com/groupee_common/emoticons/icon_razz.gif hehe

Capt.LoneRanger
03-15-2006, 02:58 PM
Now, honestly...

... are you in some way related to a guy with the nick 'raaaid'? http://forums.ubi.com/images/smilies/10.gif

FoolTrottel
03-15-2006, 03:46 PM
Try and make a left turn ...

Stackhouse25th
03-15-2006, 04:30 PM
he has a point, the wind in this game sucks

Tully__
03-15-2006, 04:31 PM
Originally posted by Capt.LoneRanger:
Now, honestly...

... are you in some way related to a guy with the nick 'raaaid'? http://forums.ubi.com/images/smilies/10.gif
No, he can't be. Raaaid seems to be incapable of a simple force analysis diagram like that.

Capt.LoneRanger
03-15-2006, 04:53 PM
Hey, Tully! Raaaid deserves the title of a professor! The one with a hat like this: http://forums.ubi.com/images/smilies/partyhat.gif

http://forums.ubi.com/images/smilies/784.gif


Well, we have implemented some physics of BoB in a game-engine from 1999 - okay it was constantly updated, but, well, we all know it's flaws.
So, think about Oleg running out and stopping you from turning further - you're simply not allowed to. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Viper2005_
03-15-2006, 05:26 PM
Your diagram is incorrect. You should carry out vector addition of the propwash and the relative wind due to the motion of the carrier. Then you'll see what the problem is...

Most fighters of WWII vintage were piston singles of a tractor configuration with a tail-wheel undercarriage.

To turn around they use a combination of differential braking and prop wash over the rudder.

When power is applied, prop wash is generated. This provides relative wind over the fin and rudder. Application of rudder acts to camber the fin, causing it to produce a lifting force which acts to yaw the aeroplane.

This is great when you're static and there's no wind.

On the carrier you aren't static.

When pointed into the relative wind it's easy to turn the aeroplane around; the relative wind is added to the propwash, and so the rudder is more effective.

However, the relative wind due to the motion of the carrier is a vector quantity, and therefore the rules of vector addition apply.

This means that the further you turn around, the greater the angle of attack produced on the fin. This angle of attack works in opposition to the camber applied by the rudder, and so you can't turn any further.

You're seeing the effects of yaw damping.

To see a more extreme version, try flying along at speed and applying full rudder, whilst holding wings level with the ailerons. You'll enter a side-slip. The yaw angle will stabilise at a finite angle.

It may be mathematically proven that in high speed flight the prop-wash velocity is insignificant. Therefore the sideslip angle you've attained is identical to the maximum angle of attack in yaw which the rudder can produce.

You will never exceed this angle aerodynamically.

On the carrier, greater "sideslip" angles may only be obtained because the propwash is significant.

However, significant prop wash implies significant thrust, and that is a problem with a tail-wheel configuration because it means that the aeroplane wants to nose over. And of course you're asking a lot of the brakes; most fighters are incapable of holding full power on their brakes; somewhere along the line your propwash is therefore going to be limited.

The only remaining option available to you is to build up a bit of speed and employ differential braking in the hope that your inertia will carry you around the corner, which implies some interesting difficulties of its own.

The fact is that if the carrier is steaming at 30 knots it's actually likely to be extremely difficult to turn around by yourself.

You'll make life easier for yourself by folding the wings (this tends to reduce the yaw stability of most fighters somewhat), but the real solution is to get some help from the crew.

MLudner
03-15-2006, 05:36 PM
Keep trying it. I had that same problem once, but since I have on more than one occasion turned an aircraft around on a carrier deck after landing to get back into take-off position for the next run.

Tully__
03-15-2006, 05:43 PM
I figured I'd best check the latest patch before I piped up, but it can be done without too much trouble. 40km/h carrier speed in an F6F-3, need full up elevator to stop the thing from nosing over and bending the prop but it only takes a short burst of about 40-50% throttle to get it round and pointed at the blunt end with brakes applied and full right rudder. I didn't try left turn but there's plenty of extra throttle left if you need a bit more.

Waldo.Pepper
03-15-2006, 05:57 PM
Turning around is easy in 404.

I think it is one of the BEST things about 404.

http://forums.ubi.com/eve/forums/a/tpc/f/23110283/m...011086714#3011086714 (http://forums.ubi.com/eve/forums/a/tpc/f/23110283/m/3011086714/r/3011086714#3011086714)

Jatro13th
03-15-2006, 07:13 PM
Viper, very good advice, and the rest of you, thanks, cause all it needed was patience and different and more delicate handling of the controls!

P.S. LoneRanger, you really know your insults don't ya? http://forums.ubi.com/images/smilies/winky.gif http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

P.P.S Krashan, you're welcome to the conversation!

triggerhappyfin
03-16-2006, 01:33 AM
At first I thought this thread were related toTHIS (http://media1.break.com/dnet/media/content/flyingfish.wmv).... http://forums.ubi.com/images/smilies/59.gif

Capt.LoneRanger
03-16-2006, 01:40 AM
I turned to use the complete deck to start my B25J in a self-made-mission. You can turn.

Capt.LoneRanger
03-16-2006, 01:58 AM
LOL, even I could fish with this method, triggerhappyfin. http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

bolillo_loco
03-16-2006, 11:14 AM
ear m8 u should try the shhh ark fin (that's pronounced "shh (long aye) ka hu" fur you yanks)

http://img.photobucket.com/albums/v358/bolillo_quemado/chunder.jpg

MLudner
03-16-2006, 05:23 PM
Originally posted by triggerhappyfin:
At first I thought this thread were related toTHIS (http://media1.break.com/dnet/media/content/flyingfish.wmv).... http://forums.ubi.com/images/smilies/59.gif

http://forums.ubi.com/groupee_common/emoticons/icon_eek.gif http://forums.ubi.com/images/smilies/blink.gif http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif http://forums.ubi.com/images/smilies/34.gif http://forums.ubi.com/images/smilies/88.gif http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

That was funny.

KrashanTopolova
03-16-2006, 05:44 PM
Originally posted by Jatro13th:

When the plane is sationary on the carrier facing forwards, and the carrier is moving with a speed of 40 Km/h then I get IAS of 40 Km/h. So far so good. The trouble comes when I try to turn the ac around. I apply the brakes, deflect hte rudder in full, and give throttle. The plane starts rotating around its wheel, but when I get almost perpendicular to carrier, the plane stops moving.

My question is: is the force applied to the rudder by a 40 Km/h wind so fearsome that a multi-thousand HP engine cannot overcome it? Was it like that IRL? Something tells me it wasn't, although I may be wrong. But if it wasn't, then this tells a lot about the FM, and maybe it should be checked up on.

P.S. Krashan, please stay out of this until we figure it out, and then say whatever you want http://forums.ubi.com/groupee_common/emoticons/icon_razz.gif hehe

_____________________________________________
The problem is too much throttle or rudder...tweak the rudder uniformly in conjunction with throttle and you will turn easily into any crosswind (cyber-speaking only - not RL).

You must be a CBF...(yes)...now I remember you...(a few others here too I see)!

CBF's wouldn't think of taking off the brakes now and again in conjunction with rudder deflection and throttle in order to have...THE WHEELS FREE-SPINNING...now would they...?

Thus the greater rotational force comes into being to turn the aircraft on the ground...

Raising the elevators takes force off the undercarriage as well...I think this was pointed out in one of the posts. It should be standard practice when taxiing over rough ground - as in RL.
_____________________________________________
'...the last time I spoke here I asked if those in the back row could hear me and a fella stood up and said he could...and that he would gladly change places with anybody who couldn't...' http://forums.ubi.com/images/smilies/shady.gif

Jatro13th
03-17-2006, 01:08 AM
HAHA, you make sense Krashan http://forums.ubi.com/images/smilies/11.gif http://forums.ubi.com/images/smilies/11.gif
Nice to hear from you again!

M2morris
03-17-2006, 01:41 AM
When I land on a carrier I just fold my wings and hit: Shift-E, and then I just let the little carrier Elves run out and turn my plane aroun by hand for me. Dont forget to release your chocks, or those little bstrds get peed off pretty bad. Not pretty.

M2morris
03-17-2006, 01:49 AM
Just kiddin, turning around is a pain. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif