Re: [COUPERS-TECH] Elevator Cable Tension

[mjoans]

----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]---- 'Coupers,   I have been watching this cable tension discussion with some interest.  I have over 16 years of experience rigging flight controls on Heavy Aircraft with the Air Force.  With the exception of the Air Refueling Boom control cables on a KC-135 (250 lbs) I can't think of any cables (flight control or other systems) that are higher than aprox. 100 lbs as measured on a tensiometer.  In fact most of the flight control cables that I have worked with have been right in the 100 lbs range.    If I understand the principles of cable tension correctly it seems to me that if you hung 100 lbs of weight on a single cable then measured it with a tensiometer it would read 100 lbs.  If it is a 2 cable system like most of our closed loop systems on flight controls are then a 100 lbs weight would measure only 50 lbs on each cable for a total of 100 lbs of force on the system.  That would mean that if I were reading 100 lbs of tension on a closed loop cable system then you are actually pulling the two ends of the system together or towards each other at 200 lbs of force.    I don't recall what the tension was that someone quoted for the 'coupe but it seems to me that if it said 150 lbs of force on the system then the cable tension reading on a tensiometer would only be 75 lbs.  not 150 lbs.  150 lbs on the tensiometer would equal 300 lbs of force on the bellcranks.  I have a hard time believing that the 'coupe is suposed to be any higher than 50 to 75 lbs as measured on a tensiometer.  I could be wrong but that is my 2 cents worth.   As a side note Advisory Circular 43.13-1B ACCEPTABLE METHODS, TECHNIQUES, AND PRACTICES--AIRCRAFT INSPECTION AND REPAIR  CHAPTER 7. AIRCRAFT HARDWARE, CONTROL CABLES, AND TURNBUCKLES is a great resourse for cable info.   Mavin Jones MSgt USAF ----- Original Message ----- From: Jim Read <[EMAIL PROTECTED]> To: Coupers Tech <[EMAIL PROTECTED]> Sent: Friday, February 23, 2001 5:31 PM Subject: [COUPERS-TECH] Elevator Cable Tension > ----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]---- > > We're talking tension here, not pressure and it seems that most of the > > respondents that have done this job have elected to use a lower figure > > than the book.  For the job in hand I consider the tension called out > to > be high.  I have no scientific evidence to back up this opinion, just > experience with other types.  I'm also aware that we get down to 32 > degrees here at VNY and that internal hanger temperatures often get > above 150 degrees in mid-summer.  Like our Canadian friend suggested, > sticking blindly to the written word and ignoring instinct and > experience is contrary to good practice, which is the basis for the > advice I originally sought.  I'll let you know what we decide. > many thanks. > jim > > > --------------------------------- > to unsubscribe send mailto:[EMAIL PROTECTED] > > ____________________________________________________________ > T O P I C A  -- Learn More. Surf Less. > Newsletters, Tips and Discussions on Topics You Choose. > http://www.topica.com/partner/tag01 > > --------------------------------- to unsubscribe send mailto:[EMAIL PROTECTED] ____________________________________________________________ T O P I C A -- Learn More. Surf Less. Newsletters, Tips and Discussions on Topics You Choose. http://www.topica.com/partner/tag01