Bonanza ADs

[Let'sgoflying!]

A friend is asking about a Bonanza AD, it has to do with the material used to make a 'pitch horn' -sounds like the part that the ruddervator actuator is attached to.
Anyone know what AD that might be? Its a 47 A35 I think.
He said it refers to a SL/SB that explains how to test the metal to determine if its Al or Mg so I will be looking for that as well.
Thanks

 

[Don Jones]

Is this it Dave?
http://www.airweb.faa.gov/Regulator...63166BCB66483459862569B30052993E?OpenDocument

Don

 

[Stache]

I believe this is the AD 89-05-02. The magnesuim fittings may have been installed as original equipment or as replacement spares.

Compliance: Required as indicated, unless already accomplished.
To prevent the failure of the magnesium elevator control fittings, accomplish the following:
(a)Within 100 hours time-in-service (TIS) after the effective date of this AD, determine the composition of the elevator control fittings in accordance with the instructions contained in Beech Service Bulletin No. 2242, Revision 1, dated August 1988.
(1)If the fittings are determined to be aluminum, no further action is required by this AD.
(2)If the fittings are determined to be magnesium, accomplish the actions specified below.

Below is the test procedures.

1. The elevator control fitting does not need to be removed to perform the following test.

2. Perform the following test on both elevator control fittings to ascertain if the fittings are of magnesium or aluminum construction.
a. Sand a one inch by one inch area of the elevator control fitting to bare metal.
b. Coat the entire sanded area with Alodine 1200, 1200s or 1201. (obtain locally).
c. Allow the Alodine coating to remain for one minute and flush with clean running water.
1) If the elevator control fitting is aluminum, a gold color will develop.
2) If the elevator control fitting is magnesium, the magnesium will turn gray or black.

3. If the elevator control fitting is of aluminum construction, prime, paint and return to service. No further action is necessary.

4. If a magnesium control fitting is not being replaced with an aluminum fitting at this time, resand to remove the effect of the alodine solution, coat with Dow 19 (instructions below) and return to service:
a. Place approximately 3/4 gallons of distilled water in a stainless steel, aluminum, vinyl polyethylene or a rubber lined container which will measure one gallon of fluid. The water should be at a temperature of between 70°F and 90°F.
b. Add 1 1/3 oz. of chromic acid (H2CR04).
c. Add 1 oz. of calcium sulphate (CAS04) to the water.
d. Add distilled water to make one gallon of solution and stir vigorously for at least 15 minutes.
e. Brush the solution in and around the bare surface of the magnesium, keeping the area wet wìth the solution for one to three minutes to produce a brown film. Do not exceed three minutes.
f. Rinse with cold running water and dry by exposure to hot air blast.
g. Apply a liberal coating of zinc chromate primer and paint. If the elevator control fittings are magnesium they must either be replaced with aluminum control fittings or be reinspected at each 25 service hour interval until they are replaced.

Stache

 

[Let'sgoflying!]

That would be it. Thanks, Don and Stache.

 

[Henning]

That would be it. Thanks, Don and Stache.

There were other AD's as well on the early ones with the small diameter horns, it's an old AD though and most have been replaced. Not many of the Mag horns left in service, usually you only find them doing a restoration on a super hangar queen.