The International Cessna 170 Association

Since things are slow (conversation-wise) I thought I’d birng up yet another curious thing about these airplanes:

The specified grease for these airplanes are what one might expect...until one reads the 100 Series Service Manual....which allows deviation from Mil-Specs if “good quality” automotive greases are utilized... And many of us do use our favorite automotive grease for things like wheel bearings, etc...

But the tailwheel grease is an interesting (if not downright comic) specification.

I don’t know how many of us have the Javelin auto-pilot installation. In fact, I don’t think I’ve ever seen one in any airplane.
And of all the autopilots I’ve used in 50 years of flying, I don’t know of ANY that control a tailwheel...
...and if any DID... I doubt they’re authorized to be operated on the GROUND anyway.

But the comment found in the 170-B Owner’s Manual struck me as both curious AND comical when it specifies MIL-L-771 1—Grease for the tailwheel.... EXCEPT IF the Javelin auto-pilot is installed... where it specifies:

“(Use MIL-G-327H grease in tail wheel with Javelin auto-matic pilot installation.)”

I hope no one gets busted by their FAA Mx Inspector over this.

I use ARCTIC CAT EXTREME LOW TEMP GREASE. Anyone who maintains and snogo's in the winter know's that to keep your steering happy and be able to turn at -20 temps or lower we have to have a excellent cold weather grease. Arctic cat has done that. Not only for cold weather but for adhesion and for water repelling water. This is what I use in all our tail-wheels and in the mains.

JP

My 170A had an auto pilot installed. A wing leveler really as best I can tell. Leroy and I still have many of the components and there are still some installed on the aircraft. I have never investigated enough to find the name of the system.

The system used the rudder only to steer and level the wings. And if you are moving the rudder, you are also moving the tailwheel. Guess they wanted to be sure one wasn't lubing the tailwheel with tar.

Given the properties of lubricants available in 1948-56 vs. those available today, I can’t help but think that most anything today would be better. JMO

George, mine had some kind of auto pilot steering gismo installed at the factory , it was attached to the rudder, which is attached to the tailwheel. Like Bruce's plane some of the stuff is still in there but not connected to anything.ie. tray, and pulleys, no cables. I have long ago forgotten what it was called, but it may have also been installed when the Javelin fuel tank was done. These records are not in my Canadian books but were from the FAA.I don't have the US log books prior to import to Canada
I remember talking to Richard Pulley about it, but can't remember the equipment name.

I looked into autopilots in the late 80s, and as I remember, the only autopilot I could find that was already approved was a Brittain, which had a pneumatic servo, intended to be powered by a vacuum pump. I thought that was odd for an airplane equipped with venturis. I thought it operated ailerons, but very well could have been the rudder.

Went on an archaeology dig tonight and found the write up where a Javelin Autopilot, in 1955, was installed and then, in 1957, removed. The only artifacts from the installation are the two fairings where the autopilot control cables exited the aft fuselage to connect to the rudder control horn.

johneeb wrote:Went on an archaeology dig tonight and found the write up where a Javelin Autopilot, in 1955, was installed and then, in 1957, removed. The only artifacts from the installation are the two fairings where the autopilot control cables exited the aft fuselage to connect to the rudder control horn.

Javelin-Autopilot-Install-&-Removal.jpg

That describes most of the remaining artifacts and large cover plugging the hole where the ADF was in my 1955 model.