Club Homepage Forums Classified Ads Buy & Sell - Everything But Airplanes Poll: Rudder AD

Me too. If someone is willing to skimp on this, what else would the cut corners on.

Hmmmm..The poll didn't imply not to comply with the AD. Just what if it was complied with by placard and not by installing the kit.

Bill
Grants Pass, Oregon

Not what I'm saying! I'm just thinking that if someone took the placard method... which is cheap and expedient and perfectly legal.... there is still nothing on the tail to prevent the rudder from jamming. Aside from a warning not to do intentional spins.

it seems to me that a piece of metal installed there would do a lot more than to prevent any potential jamming than words on a placard in the cabin.

If someone is unwilling to perhaps part with the money, time and inconvenience to get the kit, have it installed and update the logs, what else are they unwilling to do. There's a pattern here. Folks who skimp on something are prone to do the same skimping on other areas.

Believe me... I understand that the placard by itself is perfectly legal. But rather than doing the mnimum, I'd just be more comfortable with something that goes a bit over the minimum.

Do ya want your brain surgury done by a newbie who passed with a 70.0... perfectly legal.... but minimal... or the experienced pro who aced everything? Same analogy.


I'd also be interested to seee the mad dash toward the end of the window to get this done by the procrastinators. And I'll bet that it won't be to install the mod kit.

Again, I want to emphasize I am NOT saying anyone that placards the airplane is skimping. I am saying the kit installation goes beyond what is minimally required.

If on close inspection by an AI the decision is made that the mod is not needed, I see nothing wrong with the "skimping" method. My intention is to go for the mod, but it seems like an over-reaction by some one in a FISDO.

Bill D.
N3500L
AJP

Agreed if it's not needed.

Someone counld conceivably take what I'm saying to an extreme - why not redesign the 150-152... go through a whole new certifaction process to ensure that it will not ever fail mechanically. But that's silly. All I'm saying is taking the extra step is prudent!

Poobs bows to alternative points of view!

Can I just pass on the brain surgery? Not all of us require it.

If being placarded is the minimum, I won't not purchase the plane. But, what other "minimums" have occurred? Or, less than "minimum".

I'm thinking - if the rudder stop is dangerous during intentional spins, then its just as dangerous on unintentional spins. And if the spin is unintentional, then you've already got one problem - don't need two.

To me the placard is a temporary fit, until the cash shows up on the tree. 500 bucks is 500, but the risk I might take shouldn't be shared with my passenger.

Remember, the two aircraft that crashed were not properly maintained and did not meet type design.

I personally inspect rudder operation and travel, (as well as all other control surfaces), each preflight. Don't you?_

If your aircraft is properly maintained. Inspected each preflight by yourself. Annually by your mechanic. Determined to be safe. And now per this AD, a placard is also added. How does the term "minimum" apply?

Bill
Grants Pass, Oregon

Jim,
>>>You mean the best price?
Not necessarily, but maybe.

>>>NOBODY is going to develop a kit for this other than Cessna.
I was under the impression that there was a kit out by another manufacturer...perhaps I was mistaken.

>>>Cessna is the manufacturer, they did the engineering, issued the Service Bulletin BEFORE it was an AD, made the kit- which in my opinion is now considered factory parts, AND the Cessna kit and SB is in the AD, so you HAVE to use what it calls for otherwise use a AMOC. Since the Cessna kit is under $100, I really don't see a rush to make kits by another party. So, either buy a kit from Cessna, or install the placard and leave it at that. I'm amazed that the FAA allowed owners to slap a sticker on the panel and promise not to do spins. Sticker or not- it'll still spin!!!

I am amazed that on the strength of two accidents the FAA would mandate alteration of the entire fleet without individual inspections.

From the standpoint of liability, Cessna has moved to prevent future financial losses but has in essence admitted that the rudder was improperly designed, improperly tested, and occasionaly, improperly installed. I am not certain, but I believe that that opens them for lawsuits going back before the 18 yr cutoff mandated by the GA Revitalization Act. So everybody who lost somebody in a spin can take a shot at Cessna.
If I am wrong, someboady please coreect me.

Having seen Hung's pictures and hearing that it is a one hour proceedure, I am less reluctant to change the hardware. Previous to that I had read a $500 dollar figure.

Jim

I invite you to read the following report from Transport Canada. Altough there was a missing return spring on the accident aircraft, evidence found on multiple other aircraft inspected during the BST investigation, showed the importance of develloping a solution to a potential catastrophic situation. I think the rudder kit is a very cheap insurance that all C150-C152 owners should buy.




From 17 January to 04 February 2000, Transport Canada conducted a maintenance audit of another flight school operator at Saint-Hubert Airport, Québec. During the audit, Transport Canada inspectors found discrepancies that led to the grounding of 22 aircraft for various reasons. Following this maintenance audit, the operator, on 15 February 2000, submitted a Service Difficulty Report (SDR) after inspecting its fleet of 10 Cessna 152 aircraft. On five of these aircraft, there was evidence that the rudder stop plates on the rudder horns had ridden over the stop bolts. Transport Canada also submitted an SDR on the same subject. TSB investigators visited the operator the next day for preliminary examinations of the five aircraft with the rudder problems.

On 22 February 2000, four TSB investigators met at the flight school at Saint-Hubert, with representatives of Laurentide Aviation, Transport Canada, and Cessna, to examine the aircraft with suspected rudder anomalies to determine if rudder anomalies were related to the circumstances that led to the accident involving C-GZLZ. It was determined that a very hard left rudder pedal input could cause the right side of the rudder horn to deflect slightly and over-travel and hang up momentarily on the stop plate (bumper) on the top of the stop bolt. Witness marks were evident showing that this had occurred on previous occasions. However, a slight application of right rudder pedal would release the rudder. During those tests, it was not possible to make the rudder horn stop plate override the stop bolt and hook behind and below it, as was found in the accident aircraft. It was noted during these tests that the rudder was being stopped from further over-travel in its movement by contact with the left elevator. Witness marks found on the accident aircraft correspond with previous contact between the rudder and elevator.

To better understand whether and how the rudder could have over-traveled and jammed on the accident aircraft, additional tests were conducted on a similar aircraft. The test conditions included removing the right rudder bar return spring and disconnecting the right rudder cable. As with a loose rudder cable, this facilitated over-deflection of the rudder to the left. It was also determined that moving the elevator to a position more than two-thirds up--increasing the clearance between the rudder and the elevator--permitted further travel of the rudder. In that condition, a very hard left rudder pedal input permitted the rudder to over-travel and the stop plate locked below and behind the stop bolt, exactly as had been found in the accident aircraft. The rudder was locked irreversibly and had to be released by levering the rudder horn with a screwdriver. A second test, with the rudder cable reconnected, but slightly loose, and with other conditions the same, again led to a locked rudder. These tests showed that the design and condition of the stop bolt and rudder horn stop plate allowed the stop plate to over-travel the stop bolt and jam.

On 14 March 2000, Cessna notified TSB investigators that it is developing a new design for the rudder horn stop bolt to preclude the possibility of over-travel of the rudder. Cessna has notified the Federal Aviation Administration (FAA) Aircraft Certification Office that it is developing a Service Bulletin to offer the new configuration for all Cessna 150s and 152s produced after 1966. Transport Canada and the FAA are considering airworthiness actions.

The following Engineering Branch report was completed:

* LP 89/98 - Investigation of a Locked Rudder.

This report is available upon request from the Transportation Safety Board of Canada.

Complete report here:
http://www.tsb.gc.ca/eng/rapports-reports/aviation/1998/a98q0114/a98q0114.asp