Horn inspection

[Zach Grant L1011jock]

Monica and Richard,

In reading your question I was confused as the rudder weights described by SB 362A are indeed external weights on the rudder and have no bearing on the stabilator. SL 687 addresses the tip balance weights on the stab., not the rudder. I just spoke with Friedrich on this and realize it was an english translation issue with the terms used.

To answer the question pursuent to the tip weights, there is no correlation between having or not having tip weights, between 2 or 3 blade props, or any other definitive conclusion at this time. We have so few horns that are cracked relative to the fleet, and we have seen no definitive indication that vibration coupling fatigue is the culprit as some aircraft have 11000+ hrs with no cracks and some with <3000 hrs with cracks. As it stands now, the majority of the cracks have been on found on aircraft based on the west coast of the USA. This is why we need more data. Please everyone fill out and mail in the questionare as we need lots of data and fast to stop a very damaging AD from being imposed on us.

-Zach

[Hank Spellman]

Zach,

The early models of the 180 and 250 each came with either of two propellers. The 180 had either a Hartzell HC92ZK8D or a McCauley 2D36C14. The 250 had either a Hartzell HC82XKID or a McCauley 2D36C28-G.

Although it it seems unlikely that it makes any difference, perhaps the propeller model has something to do with it.

My 1959 250, with the McCauley propeller, had no cracks.

Just a shot in the dark.

Hank
Henry A. Spellman

[Matt Angst]

[T210DRVR]

[Bill Creech]

[Don Ostergard]

[Kristin Winter]

[Hansmeister]