It's great to read that the "regulators" are actually putting out information about human factors in aviation maintenance (AM, May, p. 4).

Such items as calendars and posters used by our regulators to inform maintenance personnel about human factors in maintenance can have a positive affect on the `guys on the floor'. They actually feel optimistic when the regulators relate to everyday issues. The more publications the better, but don't just put it on your web site and expect the average mechanic to go searching for the benefits about human factors in maintenance; get the information in their hands and in front of their eyes. The pocket guide/calendar does this.

Shawn Darcy

Maintenance Safety Officer, WestJet

Calgary, Canada

I read your article about the human factors program (AM, May, p. 4) ... My job is manager in Saudia Airlines in the engine overhaul shops; I am also the team quality leader in this facility. I believe human factors should be included in airframe and powerplant (A&P) school, and it should be required in recurrent training for A&P license and mechanic certification. In my personal opinion, human factors training is essential for all maintenance mechanics, and the training would do much to combat accidents and incidents due to human errors.

Essam Abuljadayal

Manager, Powerplant Support Shops

Saudia Airlines

Rigging Control Cables

Having been involved in flight control adjustment (rigging) for several decades, your article caught my interest and exemplifies a couple of problems that have been with us for quite a while (AM,.June, p. 68)

First, cable blocking. This appears to still be a little known technique to prevent control cables from becoming loose during the rig process. As your article described, this lack of knowledge contributed to the loss of life and equipment.

A note in AC 65-15A that makes a reference to "blocks" that can be used to temporarily lock the controls in place. I took a look at that paragraph, and there was no other information about what these blocks looked like, how they're used, where to locate them, or the best time to relieve cable tension. As an experiment, I took the reference to work and showed it to a few AMTs that have not, as yet, been involved with much rigging and asked them how they would go about using cable blocks. Responses went from "No clue" to some very elaborate schemes ultimately doomed to failure. So to make reference to a technique with no instructions is, in my humble opinion, worthless. A possible solution would be to revise AC 65-15A to give a more detailed description and "how-to" of cable blocking.

Second, locating necessary information in a timely manner can be a very time-consuming and frustrating endeavor. Information is scattered throughout a variety of locations and publications, to include FAA and manufacturer publications. Even within the airframe manufacture's AMM, maintenance procedures can be vague and confusing, increasing the workload on the AMT to have procedures corrected and, at the same time, accomplish the task in a legally fit and timely manner. A possible solution to this would require an industry/governmental commitment to improve technical information that would be easier and quicker to find.

Joseph Mizerak