Instrument Panel Tilt
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Instrument Panel Tilt
What is the panel tilt angle of the instrument panel in a '52 170B? Info needed to order new AI. Thanks.
Re: Instrument Panel Tilt
Instruments (typically horizons) are made for either ZERO or 7-degree tilt panels. This is important in order for the horizon line and the indicator to have full-and-correct capability or range-of-pitch.
Our 170's have "zero" tilt. (If the aircraft is levelled...the panel is vertical.)![Wink :wink:](./images/smilies/icon_wink.gif)
Our 170's have "zero" tilt. (If the aircraft is levelled...the panel is vertical.)
![Wink :wink:](./images/smilies/icon_wink.gif)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.![Wink ;)](./images/smilies/icon_wink.gif)
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
![Wink ;)](./images/smilies/icon_wink.gif)
Re: Instrument Panel Tilt
I learn something new everyday. Will you elaborate more George? I've never given this any thought, because I never heard about it before. I guess it's more of an avionics deal. What aircraft have a 7 degree tilt? And which way are they tilted? Thanksgahorn wrote:Instruments (typically horizons) are made for either ZERO or 7-degree tilt panels. This is important in order for the horizon line and the indicator to have full-and-correct capability or range-of-pitch.
Our 170's have "zero" tilt. (If the aircraft is levelled...the panel is vertical.)
Del Lehmann
Mena, Arkansas
Mena, Arkansas
Re: Instrument Panel Tilt
Many of the multi-engine aircraft have a 7-degree panel. The panel top tilts away from the pilot for better viewing.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.![Wink ;)](./images/smilies/icon_wink.gif)
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
![Wink ;)](./images/smilies/icon_wink.gif)
Re: Instrument Panel Tilt
So is the external housing of the unit made different to allow for the panel, or is it the guts of the unit that are different?
Del Lehmann
Mena, Arkansas
Mena, Arkansas
- cessna170bdriver
- Posts: 4068
- Joined: Mon Apr 22, 2002 5:13 pm
Re: Instrument Panel Tilt
Where's that documented George? I had always assumed the same thing until I had a problem with a new attitude indicator once, and (as I remembergahorn wrote:...Our 170's have "zero" tilt. (If the aircraft is levelled...the panel is vertical.)
![Confused :?](./images/smilies/icon_confused.gif)
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
Re: Instrument Panel Tilt
Miles I believe your right. Mine is pretty close to vertical when the plane is sitting on the ground. I seem to remember buying the attitude indicator for zero tilt and have had no issues to date. Bill K
Polished 48 170 Cat 22 JD 620 & Pug
Re: Instrument Panel Tilt
Good one, Miles!cessna170bdriver wrote:Where's that documented George? I had always assumed the same thing until I had a problem with a new attitude indicator once, and (as I remembergahorn wrote:...Our 170's have "zero" tilt. (If the aircraft is levelled...the panel is vertical.)) my panel was about 5 degrees from being perpendicular to the upper door sill.
I seem to have suffered another bran-pharrt....(too much fiber, I guess.)
The part numbers Cessna used for VG (Vertical Gyro/Artificial Horizon) in our airplanes are for vertical panels....and I guess I gradually made an assumption with regard to the panels themselves.... You are correct that they are tilted approximately 5-7 degrees. I called their tech-number and got a fuzzy reply that presumeably Cessna averaged the matter due to the 3-point stance of the 170 and installed instruments for zero-tilt, while the virtually-identical 172 (except for it's level, tricycle-gear stance) used 7-degree instruments. The difference in the instruments is denoted by the "dash no." I see the 170 used -2 T/B while the 172 used -5's. "Don" at tech-support said those numbers indicate vertical and tilted gyros, respectively. (It is rare that anyone at Wichita actually sounds old enough to be credible, however.)
![Laughing :lol:](./images/smilies/icon_lol.gif)
Most aircraft instrument mfr's can accomodate panels from 0 thru 8 degrees, and many will calibrate their gyros for customers, although most are produced for the most common tilts:... zero, five, seven, or eight degrees. Turn and Banks are mfr'd to specific tilt-angles but it's generally relatively unimportant by most folks because, while the rate-of-turn indicated is dependant upon the yaw about the axis...most T&B/Coordinators already have their gyros tilted 30-degrees in order to detect the yaw. The inaccuracies inherent in another error of 0-8 degrees isn't a lot of concern. Horizons are usually considered more important, presumeably because of limited remaining parallax adjustment.
As I ordered my new Sigma-Tek horizon for the latest project this subject came up and the Sigma-Tek representative looked up his data and said that the 170 should have a zero-tilt instrument. I guess I absent-mindedly relegated my brain-cells to assign the same to the panel. Thanks for catching it.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.![Wink ;)](./images/smilies/icon_wink.gif)
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
![Wink ;)](./images/smilies/icon_wink.gif)
- cessna170bdriver
- Posts: 4068
- Joined: Mon Apr 22, 2002 5:13 pm
Re: Instrument Panel Tilt
Thank YOU for doing the legwork to verify that I wasn't imagining things.gahorn wrote:...Good one, Miles!... Thanks for catching it.
![Smile :)](./images/smilies/icon_smile.gif)
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
-
- Posts: 72
- Joined: Tue Jun 08, 2010 10:34 pm
Re: Instrument Panel Tilt
The esteemed GAHorn wrote,
"Cessna averaged the matter due to the 3-point stance of the 170 and installed instruments for zero-tilt, while the virtually-identical 172 (except for it's level, tricycle-gear stance) used 7-degree instruments."
Can you tell me what the tilt angle is for a 1959 C-172? Am I correct in the George confirmed the tilt angle should be 7 degrees?
I had my AI reworked by SigmaTek (it's a 5000B model) and noted that the horizon line doesn't seem to line up. I thought it was my imagination until I read this email post. Can I check my panel with a level while the plane is sitting in the hanger?
Pete P.
"Cessna averaged the matter due to the 3-point stance of the 170 and installed instruments for zero-tilt, while the virtually-identical 172 (except for it's level, tricycle-gear stance) used 7-degree instruments."
Can you tell me what the tilt angle is for a 1959 C-172? Am I correct in the George confirmed the tilt angle should be 7 degrees?
I had my AI reworked by SigmaTek (it's a 5000B model) and noted that the horizon line doesn't seem to line up. I thought it was my imagination until I read this email post. Can I check my panel with a level while the plane is sitting in the hanger?
![Confused :?](./images/smilies/icon_confused.gif)
Pete P.
The better is the enemy of the good.
1959 C-172
1959 C-172
Re: Instrument Panel Tilt
The only living soul who correctly regards me with esteem is my dog....but is a she, a Labrador and after 14 years now seems to be disregarding me more and more. Perhaps she is finally as smart as I've been telling folks.ptporebski wrote:The esteemed GAHorn wrote,
"Cessna averaged the matter due to the 3-point stance of the 170 and installed instruments for zero-tilt, while the virtually-identical 172 (except for it's level, tricycle-gear stance) used 7-degree instruments."
Can you tell me what the tilt angle is for a 1959 C-172? Am I correct in the George confirmed the tilt angle should be 7 degrees?
I had my AI reworked by SigmaTek (it's a 5000B model) and noted that the horizon line doesn't seem to line up. I thought it was my imagination until I read this email post. Can I check my panel with a level while the plane is sitting in the hanger?![]()
Pete P.
![Laughing :lol:](./images/smilies/icon_lol.gif)
If your AI is incapable of correcting the parallax to your levelled airplane, your sitting viewpoint...you can have it calibrated for panel tilt.
You can measure panel tilt with a protractor or digital level.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.![Wink ;)](./images/smilies/icon_wink.gif)
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
![Wink ;)](./images/smilies/icon_wink.gif)
Re: Instrument Panel Tilt
I recently had my gyros overhauled by AQI in Wichita and they did a beautiful job. One issue, however, was the panel tilt that is discussed here. When I did the initial test flight after re-installation, I noticed that the AI (old "AN" type) showed about a 4-5 degree pitch down indication in level flight. I got out my protractor and noticed that the attitude taken at the upper door sill on the ground was +11 degrees and the panel showed about a +6 degree tilt for a 5 degree difference. Went flying and measured about a -4 degree panel tilt in level flight at 2000' and 2450 RPM ("high speed" cruise configuration). I'm sending it back tomorrow for adjustment. I'll let you all know the results.
Just thought I would throw out some "real world" tilt numbers if it helps anybody.
Just thought I would throw out some "real world" tilt numbers if it helps anybody.
Former Caretaker of N4410B '55 170B
s/n: 26754
s/n: 26754
Re: Instrument Panel Tilt
Coincidence? I just flew my 170A today with a freshly-overhauled AI (by AQI) and noticed nearly the exact same thing. I previously had thought the 170 to have a zero-tilt panel, but now am wondering. AQI may have 2 indicators coming to them this week!busav8or wrote:I recently had my gyros overhauled by AQI in Wichita and they did a beautiful job. One issue, however, was the panel tilt that is discussed here. When I did the initial test flight after re-installation, I noticed that the AI (old "AN" type) showed about a 4-5 degree pitch down indication in level flight. I got out my protractor and noticed that the attitude taken at the upper door sill on the ground was +11 degrees and the panel showed about a +6 degree tilt for a 5 degree difference. Went flying and measured about a -4 degree panel tilt in level flight at 2000' and 2450 RPM ("high speed" cruise configuration). I'm sending it back tomorrow for adjustment. I'll let you all know the results.
Just thought I would throw out some "real world" tilt numbers if it helps anybody.
The good news is AQI is very good about correcting problems. I had an altimeter that had been overhauled by them in 2010. I had a major project with the airplane and didn't fly it until this spring, at which point I noticed my altimeter thought we were at 74,500 MSL! They fixed the 10,000 pointer at no charge, nearly 2 years after they did the overhaul.
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--Josh
1950 170A
1950 170A
Re: Instrument Panel Tilt
Josh...is that a picture of your gyro ...WHILE IT IS SPINNING AT PROPER SPEED? Or is it while it's sitting on the ground in the hangar at REST? (Makes a difference! Also makes a difference if the airplane is airborne or not.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.![Wink ;)](./images/smilies/icon_wink.gif)
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
![Wink ;)](./images/smilies/icon_wink.gif)