So I finally got around to addressing the rigging on my '47 140.
I had a heavy left wing in cruise that required constant aileron and rudder pressure for straight & level flight.
Two turns out on the "light" (right) wing rear strut per SL 49 and Voila! , it now cruises fairly flat, albeit with the ball to the right.
So what's next to get the plane to cruise straight & level, ball centered ?
Thnks!
Ball is right of center in cruise
Forum rules
You must be a member of the Cessna 120-140 Association in order to post new topics, reply to existing topics, or search for information on this forum. Use the "Join" link in the red menu bar.
You must be a member of the Cessna 120-140 Association in order to post new topics, reply to existing topics, or search for information on this forum. Use the "Join" link in the red menu bar.
-
- Posts: 2
- Joined: Sun Apr 19, 2020 11:46 am
- Location: Europe
- Name:
- Aircraft Type: 140
- Occupation-Interests: FBO Owner, A&P/IA
- Contact:
- 6643
- Posts: 2383
- Joined: Tue May 01, 2018 7:00 am
- Location: KLCI, NH
- Name: John C
- Aircraft Type: 1946 C140/C90
- Occupation-Interests: A&P, semi-retired
- Contact:
Re: Ball is right of center in cruise
If you needed both rudder and aileron, you need to correct both. IF you apply rudder to center the ball, I expect the plane will start turning, right? Anyhow, first thing to check is your rudder pedal springs. They are not (supposed to be) the same length. Put the tailwheel up in the air and center the pedals. Is the rudder centered? Adjust the cables so it is. Now, let go if the pedals. Do they stay centered? If not look at the springs.
When all that is set, look at the tail wheel. Is it centered when the rudder is centered? If not it will act like a rudder trim tab.
Lastly fly the plane hands off. Use the rudder to center the ball. Is the plane turning? If not adjust he trim tab on the rudder. If turning, adjust the lift strut. Wash, rinse, repeat. I'm guessing you'll need to remove a little of the aileron correction you made and add some rudder correction, unless you changed something in the first steps.
(All from memory, feel free to correct me if I'm confused!)
John Cooper
www.skyportservices.net
www.skyportservices.net
-
- Posts: 231
- Joined: Tue May 01, 2018 7:00 am
- Location: Ann Arbor, MI
- Name: Ray Hunter
- Aircraft Type: C-140
- Occupation-Interests: Retired AF, B-17, UH-1, pilot for Yankee Air Museum
- Contact:
Re: Ball is right of center in cruise
I had a similar problem. Turns out that I had a broken rudder return spring. Yes, they are not both the same length.
-
- Posts: 2
- Joined: Sun Apr 19, 2020 11:46 am
- Location: Europe
- Name:
- Aircraft Type: 140
- Occupation-Interests: FBO Owner, A&P/IA
- Contact:
Re: Ball is right of center in cruise
Thanks guys - will check rudder cables and TW, and yes I do remember seeing the un-equal length return springs last time I was in there.
A&P/IA
- 8413
- Posts: 88
- Joined: Sun Mar 03, 2019 3:11 pm
- Location: Bonney Lake, WA
- Name: Josh C
- Aircraft Type: 140A/C90-14F
- Occupation-Interests: Telecommunications
- Contact:
Re: Ball is right of center in cruise
I'm curious if the rigging should be adjusted without taking into account the weight of a passenger? Isn't it normal for the left wing to be slightly heavy due to the pilot weight being left of the centerline of the fuselage when not flying with a passenger?
Josh
Josh
- 6643
- Posts: 2383
- Joined: Tue May 01, 2018 7:00 am
- Location: KLCI, NH
- Name: John C
- Aircraft Type: 1946 C140/C90
- Occupation-Interests: A&P, semi-retired
- Contact:
Re: Ball is right of center in cruise
I guess if you're going to do that, you should also consider which wing tank you usually use first...
Just to beat a dead horse, the spring portion of the rudder springs is the same. It's one of the loops that is longer to account for the fact that one of the rudder bars is forward of the other.
John Cooper
www.skyportservices.net
www.skyportservices.net
Who is online
Users browsing this forum: Bing [Bot] and 9 guests