Elevator up & down travel

Discussion for builders, pilots, owners, and those interested in building or owning a Onex.

Re: Elevator up & down travel

Postby Mike53 » Mon Aug 11, 2014 3:09 pm

I will have to join what I am assuming is a common problem for some Onex owners.
I have no idea how one would accurately measure for the 25 degree up and down travel using the cord line of the stab so I have measured from the top of the stab as per plans and after grinding as much as I am willing to from the horn and even a little from the bracket where the upper arm of the horn was contacting it and can only achieve 165 degrees where it calls for 160 degrees to achieve the 25* up travel.
Down travel is not an issue and is 27*.
Has anyone achieved 25* (160* measured from top of stab) up travel by simply grinding material from the horn?
Apparently 18 degrees is all we require according to Tech Support so I guess I will settle for 20*
Thanks .
Mike Turrell Onex 080
Mike
I know but one freedom, and that is the freedom of the mind.
Antoine de Saint-Exupery
Reserved C-FONX for the 80th Onex,Hummel 85HP ,Tri gear,GRT Mini X EFIS,and EMS,iFly 740 GPS
User avatar
Mike53
 
Posts: 480
Joined: Mon Jun 20, 2011 10:00 pm
Location: Dutton,Ontario , Canada

Re: Elevator up & down travel

Postby onex0127 » Mon Aug 11, 2014 6:25 pm

Mike , I was only able to get 20 on my aircraft but the factory said 18 would be okay.

Roy Taylor
onex0127
 
Posts: 22
Joined: Tue Mar 25, 2014 3:40 pm

Re: Elevator up & down travel

Postby Mike53 » Tue Aug 12, 2014 5:09 pm

Thanks Roy.It's a bit frustrating to follow the plans ,and considering everything is pre drilled ,to come up short of the design ideal.
Something is not right in Peoria :(
Mike
Mike
I know but one freedom, and that is the freedom of the mind.
Antoine de Saint-Exupery
Reserved C-FONX for the 80th Onex,Hummel 85HP ,Tri gear,GRT Mini X EFIS,and EMS,iFly 740 GPS
User avatar
Mike53
 
Posts: 480
Joined: Mon Jun 20, 2011 10:00 pm
Location: Dutton,Ontario , Canada

Re: Elevator up & down travel

Postby thomasjones42 » Wed Aug 13, 2014 8:38 am

Ground my first rudder horn to the point of discomfort and then bent with a torch. Got to around 19 degrees from the flat. Didn't like the looks of the horn at that point and ordered a new part. Measured one in the interim that has been flying without problems for a couple years and it was 14 degrees up from the flat. With minor grinding got to 17+ degrees with the new horn and quit.

Tom Jones
Onex #133
thomasjones42
 
Posts: 77
Joined: Wed Sep 04, 2013 12:26 pm

Re: Elevator up & down travel

Postby Don_P » Sat Nov 08, 2014 12:31 am

Here are a couple of suggestions for fellow Onex builders having trouble with the elevator up deflection. These, however, only solve the deflection problem up to the point of mounting the vertical stabilizer, as there will be additional clearance problems after that. As suggested on the drawing, I ground down the up deflection stop on the elevator horn's pushrod arm, removing about 1/8 inch of material. (Taking off more than that will cause the pushrod plate to extend out beyond the stop.) Next, in order to provide clearance for the nut and the head of the AN4 bolt (the one that holds the pushrod to the horn), I cut notches in the Upper Fuselage Attach Angle, ONX-T08-13. (Would have posted a photo, but I see the board quota has been exceeded.) The notches keep the bolt head and the nut from striking the underside of the angle before the stop strikes the vertical leg of the angle. Doing these two things achieved an upward deflection of about 20 degrees (measured through the centerline of the elevator). This, however, was prior to putting the vertical stabilizer in place. Builders will discover that doing this will pose clearance problems near the root rib of the stabilizer. To attack that problem, I will be turning the root rib attach angle over, relocating the attach bolts and cutting other chunks out the tail post as necessary. Messy work. By the way I contacted Kerry Fores about the up deflection problem, and he said that flight testing had shown that 18 degrees up worked well for the Onex. Based on this. I hope to achieve at least that much with my planned mods to the vertical stabilizer.
Don
Onex 0095
N464D (reserved)
User avatar
Don_P
 
Posts: 39
Joined: Thu Apr 11, 2013 1:33 pm
Location: Seabrook, Texas

Re: Elevator up & down travel

Postby SonexEZ » Fri Dec 18, 2015 9:58 pm

I just noticed my elevator is not even left and right side off 1/4 " has anyone else had this problem
I didnt build this sonex so i am not sure it can be changed now
SonexEZ
 
Posts: 135
Joined: Sat Aug 29, 2015 12:38 pm
Location: central west coast Florida

Re: Elevator up & down travel

Postby gammaxy » Sat Dec 19, 2015 12:44 am

I have a hard time understanding almost all of your posts. Are you saying the trailing edge of one elevator is 1/4" higher than the other? If not, explain where/how are you measuring the 1/4"?

It would be pretty difficult to build it with the trailing edge of one 1/4" higher than the other since the horn and root ribs should all be clamped together against a flat surface during initial assembly. I guess one elevator might have a little extra twist, but from your description, it is impossible to tell what you are talking about.

As far as affecting flight characteristics, I imagine it would probably give you an imperceptible amount of roll and a similar amount of extra drag. I probably wouldn't try to fix it.
Chris Madsen
Aerovee Sonex N256CM
Flying since September 2014
Build log: http://chrismadsen.org
gammaxy
 
Posts: 593
Joined: Wed Sep 04, 2013 9:31 am

Re: Elevator up & down travel

Postby Concorde » Sat Dec 19, 2015 9:35 am

Check your end caps and see they're straight.
Ben
Sonex # 1684
Tri-Gear, Dual Control
Rotax 912uls
N379BS reserved.
Concorde
 
Posts: 176
Joined: Sun Aug 10, 2014 2:11 pm
Location: North Carolina

Re: Elevator up & down travel

Postby 13brv3 » Mon Dec 28, 2015 11:03 am

thomasjones42 wrote:
When I recieved my second set of root ribs (which I did not use) and new rudder horn, I noticed that these new root ribs were not pilot drilled.

Tom Jones
ONEX kit 133


Thanks for all the details Tom. FWIW, my kit is #191, and the root ribs are not pre-punched. They must have realized those holes were causing an issue with the up travel. I'll hedge my elevator horn forward a bit as a precaution, since more up is always better than more down when it comes to elevators.

Cheers,
Rusty
Rusty
Onex- Rotax 912 (130 hours and counting)
Fixed wing, gyroplane, A&P
13brv3
 
Posts: 432
Joined: Fri Sep 25, 2015 11:59 am
Location: Tellico Plains, TN

Previous

Return to Onex

Who is online

Users browsing this forum: No registered users and 4 guests