Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

VS offset

Matronics Email Lists Forum Index -> RV4-List

View previous topic :: View next topic

Author Message

SSampson.SLN21(at)london.
Guest

Posted: Fri Apr 13, 2007 12:29 am Post subject: VS offset

I asked this question on Vansairforce but got  nothing from the -4 community. I thought I would try here, since it must have  been considered. 

  

 With all the -4 flying in the USA is there any  'conventional wisdom' about offsetting the VS at the front spar to the left to  reduce the need for right rudder in order to fly in trim?



I found a bit  about it in the matronics archives back in '98 but nothing since. They were  talking 1/4". The -9 is certainly designed this way and I expect the  -7.



If yes, how much offset? Also does it mean you have to throw the VANS  fairing out?



Thoughts?

  

 Thanks, Steve.

   [quote][b]

efortner(at)ctc.net
Guest

Posted: Fri Apr 13, 2007 9:33 am Post subject: VS offset

I am building a RV-4 but have not worked on it in a  while. I do remember building in offset to the vertical stablizer.  I

 don't remember if it was 1/4 inch or 3/8 inch but  was built

 in when I attached it.Don't recall if it was in the  instructions or not but I did read it somewhere to do that.

 Earl Fortner, Harrisburg, NC

 [quote]   ---

Oldsfolks(at)aol.com
Guest

Posted: Fri Apr 13, 2007 1:11 pm Post subject: VS offset

I have built two  RV-4's and set the HS in line with the  fuselage.  There are enough variables in building with out adding more  possibilities of out -of-trim.

  

 Bob Olds 

 RV-4     -  N126RV  &  N1191X

 Charleston,Arkansas



See what's free at AOL.com. 

  [quote][b]

halbenjamin(at)optonline.
Guest

Posted: Fri Apr 13, 2007 5:54 pm Post subject: VS offset

Hi Steve C

  6nbsp;

 I considered 6nbsp;offsetting the VS C but after 6nbsp;talking to a couple of people with flying 4s (Including Van 7s) I decided to 6nbsp;mount it straight as per plans E

  6nbsp;

 Hal Benjamin

 RV4 C Long Island C NY

 Endlessly tweaking canopy frame 6nbsp;



---

jlisler(at)alltel.net
Guest

Posted: Sat Apr 14, 2007 1:49 am Post subject: VS offset

I built mine with a 1/4" offset. I did not use the  Vans tail intersection fairing. It was not even close and it looked  awful. I layed up a new fairing that fits really good so far. As for the  offset, I still need the pressure of your foot resting on the right rudder  peddle to center the ball.  I guess I will eventually put on a  trim tab.

  

 Jerry Isler

 Donalsonville, GA

 RV-4 N455J

 16 hrs and counting

    [quote][b]

SSampson.SLN21(at)london.
Guest

Posted: Sat Apr 14, 2007 9:08 am Post subject: VS offset

Thanks everyone for the VS offset info. On balance  I think I have been talked out of the idea. I had thought that since the later  RV are built with the VS offset, it would make lots of sense, but though  there was some, there was not a lot of support. Cheers,  Steve.

   [quote][b]

efortner(at)ctc.net
Guest

Posted: Sat Apr 14, 2007 9:31 am Post subject: VS offset

I would suggest you research it a little more. I  have yet to see and RV-4 that did not have a wedge or trim tab on the rudder.  How about asking Van. I am sure he

 would reply to your request and I doubt if there is  anyone that knows more about the RV-4 than Van.

  

 Earl

 [quote]   ---

cubflyr(at)comcast.net
Guest

Posted: Sun Apr 15, 2007 8:31 am Post subject: VS offset

Steve: 



When I was first building (George Bush The First was president) I had been

working with airplanes for years (since Nixon was president; yikes!). Since

I was now building my own, I looked at every airplane I could, factory or

custom built, which you should also do. I also have a 1946 J-3 Cub in the

hangar and could look at it. Almost ALL of them, from the fastest to the

slowest, had an offset vertical fin. I also noticed some rather humongous

rudder trim tabs on the two RV models that were out: the -3 and the -4, then

later on the -6. And some of them were not pretty. (Do NOT just stick a

piece of flat stock on the rudder; THAT is ugly.) I decided to offset my

vertical (I am the factory, after all) and, although I can't remember how

much, I believe it was 1/4 inch. Then I went flying. I found I still had to

hold a little rudder in level flight and ended up putting on a trim tab

anyway, but smaller than most I had seen. I found myself wishing I had

offset it more. But how do you know until you put air under the wings? Trim

flight involves so many factors.



The tail fairing was discarded almost as it came out of the box: from the

box to the trash. I built my own that has a glove-like fit and I like it. 



Trim tab: an aluminum wedge plate that sits at the trailing edge. Placement

is a controversial issue: it is my opinion that the lower (or higher, what

ever you don't mind people seeing) may work better. I place mine where I saw

most others placed: about in line with the middle hinge of the rudder. That

may not be the best place as the rudder may not have as much authority there

due to the disturbed air from the fuselage, but I am not sure because I

didn't play with the up and down as much as I should have. The Bugs know:

there are rarely any bugs on the tail fairing. Most bugs start about 8

inches above the fairing, meaning that the air is disturbed from the

canopy/fuselage and may not be reaching the trim tab as well as it could.

Tufting would also help determine where to put it but to see back there

necessitates formation flying with you and someone else that ALSO knows

formation flight. 



SO: when you are duct taping your wooden trim tab test model on the rudder

for flight trials, play with the size (height and width) as well as the

angle that you need. But also, once you found the size that works best for

feet on the floor flying AT CRUISE, move it up and down the rudder to see

where it is most effective. You do NOT want to fly everywhere with your foot

pressed against the rudder for the next 3000 hours. Also remember this has

to be done AFTER the main gear leg fairings are in place because they can

influence how straight the airplane flies. Suzie Q is one of the straightest

airplanes I have flown. There is NO elevator sticking up or down from the

horizontal when I am in cruise and solo, minimal baggage. Even with a

passenger only about 1/8 inch sticks up. She cruises, once trimmed, feet on

the floor.



I LOVE my airplane. So will you.



Michael

N232 Suzie Q

1038 hours, more to be put on this morning......

SSampson.SLN21(at)london.
Guest

Posted: Sun Apr 15, 2007 11:05 am Post subject: VS offset

Brian, calling the factory from here doesn't work  too well, so I will be very interested to hear if you manage to engage them in a  discussion, and more importantly what they have to say. WRT Smokey, I have seen  no input, but I sense he catches up in blocks. Perhaps he is away a lot since it  is the sort of thing he normally joins in on.

  

 No, my tent is not folded! I was just trying to get  some reaction...which appears to have worked. It is not a thing which I need to  act on for a while, since the next major operation is the dreaded canopy. Just  trying to get my ducks lined up though.

  

 Glad you are also interested. Its a big  help.

  

 Cheers, Steve.

 [quote]   ---

DFCPAC(at)aol.com
Guest

Posted: Sun Apr 15, 2007 11:32 am Post subject: VS offset

steve,

  

 i did not build my rv-4, but i did check it and it has a very little  offset. and i still have one of those little angle blocks on my rudder. before i  painted the plane i taped it on and got what i wanted. no falling asleep right  foot.

  

 good meeting you last week.still fooling around with that canopy? i'll try  to fly over next Saturday and maybe we can do some flying.

  

 regards

 danny

 rv-4

 N2275S



See what's free at AOL.com. 

  [quote][b]

smokyray(at)yahoo.com
Guest

Posted: Sun Apr 15, 2007 4:00 pm Post subject: VS offset

Steve, Danny,



  I helped a friend assemble an RV4 with 1 degree right offset in the vertical stab. I thought at the time it was a great idea, and it was. The aircraft flew hands off and needed no rudder trim up to 170mph. Above 170mph up to VNE it would displace the ball to the middle of the "centered" reference line. His cruise speed was 155 knots (170 mph) so it really worked great. 

 

I highly recommend the mod, it works!



Rob Ray



DFCPAC(at)aol.com wrote:[quote]     steve,

  

 i did not build my rv-4, but i did check it and it has a very little  offset. and i still have one of those little angle blocks on          Ahhh...imagining that irresistible "new car" smell?

 Check out [url=http://us.rd.yahoo.com/evt=48245/*http://autos.yahoo.com/new_cars.html;_ylc=X3oDMTE1YW1jcXJ2BF9TAzk3MTA3MDc2BHNlYwNtYWlsdGFncwRzbGsDbmV3LWNhcnM-]new cars at Yahoo! Autos.[/url]  [quote][b]

smokyray(at)yahoo.com
Guest

Posted: Sun Apr 15, 2007 4:11 pm Post subject: VS offset

Guys,



OOPS, I meant the other right...1 degree LEFT offset producing right rudder! I get Lysdexic sometimes!



Smokey

Rob Ray <smokyray(at)yahoo.com> wrote: 	  Quote: 	
		   Steve, Danny,



  I helped a friend assemble an RV4 with 1 degree right offset in the vertical stab. I thought at the time it was a great idea, and it was. The aircraft flew hands off and needed no rudder trim up to 170mph. Above 170mph up to VNE it would displace the ball to the middle of the "centered" reference line. His cruise speed was 155 knots (170 mph) so it really worked great. 

 

I highly recommend the mod, it works!



Rob Ray



DFCPAC(at)aol.com wrote: 	  Quote: 	
		       steve,

  

 i did not build my rv-4, but i did check it and it has a very little  offset. and i still have one of those little angle blocks on          Ahhh...imagining that irresistible "new car" smell?

 Check out new cars at  size="2"> 	


	


[/quote]

           Ahhh...imagining that irresistible "new car" smell?

 Check out [url=http://us.rd.yahoo.com/evt=48245/*http://autos.yahoo.com/new_cars.html;_ylc=X3oDMTE1YW1jcXJ2BF9TAzk3MTA3MDc2BHNlYwNtYWlsdGFncwRzbGsDbmV3LWNhcnM-]new cars at Yahoo! Autos.[/url]  [quote][b]

SSampson.SLN21(at)london.
Guest

Posted: Sat Apr 21, 2007 4:13 am Post subject: VS offset

Brian, did you talk to the factory yet? Thanks,  Steve.

 [quote]   ---

Display posts from previous:

	Matronics Email Lists Forum Index -> RV4-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum