The International Cessna 170 Association

OK... I understand... you are hooking yours to the elevator outer hinge instead of where I've illustrated at the outer stab/leading edge above....

...which leads to another potential problem, (especially with 170 and 170A models due to their heavier elevators.)

If the elevator is not restrained with some form of gust-lock, then wind and prop-blast from other aircraft may lift and DROP the elevator onto it's stops. As Steve Grimsley's article on elevator bellcrank support BRACKET CRACKS recently addressed, this can cause damage to the upper attach hole areas. It's a good idea to have all elevators, regardless of model, secured with gust-locks (the simplest being the seat-belt looped thru the control wheel.)

Yes I hook mine into the top hinge area not at the end of the stabilizer as in you picture. BTW the hinge area is where Cleo Bickford's drawing of this device depicts. I found his drawing from 1972 as well.

Yes I agree a B model elevator needs to be secured in one position and when I had a B model elevator I also had a telescoping rod inside the cabin that fixed the elevator down.

I'm not convinced that the unbalanced elevators found on the A and '48 have the same problem. They are very heavy. My partner has been tying this airplane down for 35 years outside. He's been using a similar system as this but made with steel tie rods and attached at the hinges as I have. With his system if you try to lift the elevator much you will jam it against the top elevator skin eventually causing damage. There is no skin damage and he hasn't felt the need to secure the elevator down in 35 years. Not a definitive answer to whether the early elevator should be secured but one that might make you think your OK without it.

Certainly no harm in securing all elevators and I like my extendable rod from the seat to the yoke to hold it down.

It's not the B-models that receive all the damage to their bellcrank brackets. It's ALL models, and the early models are more susceptible than the B-models because it is the DOWN stops that cause the damage. (Heavier elevators stress the downstops more than lighter/balanced elevators.)

Umm we have quite a lot of wind up here in the far north and what I use for a rudder system is to take two 1X4's and glue some closed cell foam (read sleeping pads 3/8" thick) I drill a hole in each end for a bolt and wing nut and the whole affair goes fore and aft from the leading edge of the vertical stabilizer to past the end of the rudder. It wraps the rudder and the vertical stab together and is pretty bomb or wind proof. I have not had a problem with this type and yes it does take some space in the aircraft but if at home base is probably the way to go.

If you have a Super or other Cub, two 2X4's top and bottom on the rear strut will keep it from being collapsed in wind downloads fromthe aft (rear wind loads).

gahorn wrote:and the early models are more susceptible than the B-models because it is the DOWN stops that cause the damage. (Heavier elevators stress the downstops more than lighter/balanced elevators.)

George, you are assuming the elevator is lifted at all in order for it to be slammed into the stop. I'm saying in PA I haven't seen wind that has done that yet on the heavy unbalanced elevator. Apparently my partner hasn't seen it in 35 years of ownership either which is why he doesn't insist on protecting against it. I don't have any heart burn with someone using an elevator lock don't get me wrong. I will say I wouldn't have left my B model balanced elevator unsecured over night, my unbalanced A model elevator is not secured.

Bruce Fenstermacher wrote:

gahorn wrote:and the early models are more susceptible than the B-models because it is the DOWN stops that cause the damage. (Heavier elevators stress the downstops more than lighter/balanced elevators.)

George, you are assuming the elevator is lifted at all in order for it to be slammed into the stop. I'm saying in PA I haven't seen wind that has done that yet on the heavy unbalanced elevator. Apparently my partner hasn't seen it in 35 years of ownership either which is why he doesn't insist on protecting against it. I don't have any heart burn with someone using an elevator lock don't get me wrong. I will say I wouldn't have left my B model balanced elevator unsecured over night, my unbalanced A model elevator is not secured.

Bruce, I have seen the damage George talks about on A models. I don't think it comes so much from the wind as from people either taxing without holding the yoke back or some that hold the yoke back but then just let the elevator drop. If you don't get the elevator off the stop while taxing that is a lot of weight bouncing on that stop, especially on a grass runway.

Interesting observation Walt.

It's my belief that ALL causes of elevators hitting the stops is harmful, whether caused by wind, prop-blast, or passers-by handing them, and that is ample cause for securing the elevator with control locks.

Certainly, it is good technique to taxi with the elevators held off the (lower) stops to prevent slamming.... to my knowlege, upper stops have not shown evidence of damage from taxying with elevators held in the up position, nor have they shown damage from locking them in the up position.

I have also observed many airplanes with damaged rudder-stops, presumeably from failure to use rudder gust-locks. On a few airplanes, I've seen evidence of rudders contacting the inboard-ends of elevators as the result of damaged/mal-adjusted rudder stops. (Look at the rudder and see if evidence of "scraping" exists from the elevator inboard-trailing-edge contact.)

gahorn wrote:...I have also observed many airplanes with damaged rudder-stops, presumeably from failure to use rudder gust-locks. ...

Here's what can happen to the rudder horn if rudder gust locks aren't used:

http://www.cessna170.org/forums/downloa ... &mode=view
http://www.cessna170.org/forums/downloa ... &mode=view

See this thread for more details.

Rather than make something from twine that wraps around a light, I just purchased a real gust lock. It seems foolish to risk damaging your $40,000 airplane when for $200 you can purchase a quality gust lock.

http://www.gustlock.com/

I have the same control lock - it is easy to use and it is great with the elevator and aerolons.
After putting it on go walk to the tail and try to move the rudder left and right. I think you will
be adding a twine rudder holder as the control lock does not stop the wind from beating the
rudder to death.

Good photo demonstration Miles. At least it didn't RUST, thanks to the Continental oil leak syndrome Aluminum will rust won't it My tail wheel springs sure don't rust. They seem to stay well lubercated

mekstrand wrote:Rather than make something from twine that wraps around a light, I just purchased a real gust lock. It seems foolish to risk damaging your $40,000 airplane when for $200 you can purchase a quality gust lock.

http://www.gustlock.com/

SteveF wrote:I have the same control lock - it is easy to use and it is great with the elevator and aerolons.
After putting it on go walk to the tail and try to move the rudder left and right. I think you will
be adding a twine rudder holder as the control lock does not stop the wind from beating the
rudder to death.

The York gust lock allows considerable strain to be placed upon the rudder control-cable system, subjecting it to the possibility of damaged pulleys and stressed brackets/bulkheads, and is more dead weight to haul around taking up space.

gahorn wrote

"The York gust lock allows considerable strain to be placed upon the rudder control-cable system, subjecting it to the possibility of damaged pulleys and stressed brackets/bulkheads, and is more dead weight to haul around taking up space."

George,

I'm no expert, but I believe the entire rudder control system was designed to handle the loads generated by full rudder deflection at maneuvering speed. I'm really not concerned about the loads that the system may encounter as a result of breezy winds and the York gust lock damaging my aircraft. By the way, the York lock is almost identical in function to the "factory original" gust lock Cessna sold with our aircraft.

If you feel the best solution is wrapping twine around the position light at the end of your rudder, I respectfully disagree. You are correct about the twine weighing less than a York gust lock. I have elected to "haul around" the 2 pound gust lock and forgo the addition of a third attitude indicator in my aircraft.

mekstrand wrote:gahorn wrote

"The York gust lock allows considerable strain to be placed upon the rudder control-cable system, subjecting it to the possibility of damaged pulleys and stressed brackets/bulkheads, and is more dead weight to haul around taking up space."

George,

I'm no expert, but I believe the entire rudder control system was designed to handle the loads generated by full rudder deflection at maneuvering speed. I'm really not concerned about the loads that the system may encounter as a result of breezy winds and the York gust lock damaging my aircraft. By the way, the York lock is almost identical in function to the "factory original" gust lock Cessna sold with our aircraft.

If you feel the best solution is wrapping twine around the position light at the end of your rudder, I respectfully disagree. You are correct about the twine weighing less than a York gust lock. I have elected to "haul around" the 2 pound gust lock and forgo the addition of a third attitude indicator in my aircraft.

My comments were not directed as a personal attack or criticism. They were intended to bring to attention the fact that the York system does not protect either the rudder OR the rudder control cable/pulley system. The fact it mimics the system Cessna discontinued as optional equipment is irrelevant, IMO, as it mimics as well the same defects of that system.

The FAA has recently issued revised definitions of maueuvering speed, by the way, which I'll try to find/post a copy. In any case, manuevering speed has no relevance to control system locks.