Announcement

Collapse
No announcement yet.

Quantum luff line checks

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Quantum luff line checks

    Regarding the latest service bulletins from P & M, can the luff lines be disconnected whilst wing still rigged but off trike etc or does the wing have to be de-rigged, I was checking them today with no issues found but the bulletin mentions disconnecting lines if putting shrink tubing protectors on etc, any advice welcome,

  • #2
    Quantum luff line checks

    Chris,

    The luff lines on the Q are connected to the wing via small U shaped items I don't know the name of. With the wing still tensioned, by lifting the batten where the luff line attaches, and its opposite number on the other wing, you can relieve the tension enough to disconnect the luff line, thus leaving you with the cloth strap under no tension. If you want to you can then have a really good look at the material where it goes through the eyelet, and if there is any wear, and assuming it's only minor, then fit some sort of plastic tubing. As long as there's enough room left for the loop of the fabric to be reattached to the U shaped fastener you won't have any problems.

    Obviously if you've got a mate with you to help by lifting the opposite batten end for each luff line then it makes the job that much easier, but it can be done on your own, as I know from experience.

    Best regards,

    Bob Hood
    XL's forever! Well, one of them anyway. It's all I can afford, not to mention the Raven and the Mini-Max. Oh, and I almost forgot the Spectrum as well :-)

    Comment


    • #3
      Quantum luff line checks

      Thanks for that Bob,
      If I may, can I pick your brains just a bit further as my usual source/inspector is out of the country at moment,
      I think my luff lines are not in the correct pulleys at the top end, I can see how to change their positions but can the all the luff lines be detached whilst wing still tensioned as the top pulley looks like it has to be detached to move them around the pulley positions,

      Thanks,
      Chris

      Comment


      • #4
        Quantum luff line checks

        Chris,

        As far as I recall, my luff lines all go through one pulley, but if you want to move yours around I guess you must have a dedicated pulley for each one? If that's the case then I think the longest one is supposed to go through the top pulley (nearest the kingpost), the middle one through the middle pulley, and the shortest one through the bottom pulley. That way they don't get in each other's way.

        You should be able to disconnect the luff lines one at a time, till all three are disconnected at one end (usually the same end, such as right wing or left wing for all). Then you can take out the pin on the bottom luff line pulley (furthest from the kingpost), then the middle one, then finally the top one. Now you can put the longest luff line on top of the top pulley, then put its pin back in. Then do the middle one, and finally the bottom one, which should have the short luff line going through it.

        With the luff lines arranged on the correct pulleys you can now reattach each of the luff lines to their respective connectors on the wing you took them off.

        Best regards,

        Bob Hood
        XL's forever! Well, one of them anyway. It's all I can afford, not to mention the Raven and the Mini-Max. Oh, and I almost forgot the Spectrum as well :-)

        Comment


        • #5
          Quantum luff line checks

          Chris,

          The reason I said to take out the pins on the pulleys was because as far as I know, the luff line ends won't go through the gap between each pulley and the holding straps it sits between. So you have to take the pins out (noting which hole each went through) then put the luff line cable on top of the pulley, then push the pulley back into the gap between the parallel metal straps (for want of a better word) and position it so that the pulley pin can be pushed through from one strap to the other. It's probably best to push the pins down from on top, so that if you lose the security ring that holds it in place, it won't necessarily fall out and let the pulley fall out as well.

          With all the hooha about the security rings lately, it might be wise to replace them with stainless steel split pins while you've got the pulley block apart.

          Best regards,

          Bob Hood
          XL's forever! Well, one of them anyway. It's all I can afford, not to mention the Raven and the Mini-Max. Oh, and I almost forgot the Spectrum as well :-)

          Comment


          • #6
            Quantum luff line checks

            Thanks again Bob,

            I also did some digging on this forum and found a pic of similar problem a few years back with "Henry Long" on his wing, the luff lines on my wing have separate pulley wheel for each line all together in a block up near king post so to move any you have to disconnect them all as you've explained, I'll have a look at the pins to see about changing over to stainless split pins as you suggest when working through it,

            Thanks

            Chris

            Comment


            • #7
              Quantum luff line checks

              From memory, if you have three pulleys, it's best to run the outer lines over the centre pulley. This line has the greatest tension, and if it is over one of the outer pulleys (as I've seen them), it tends to pull the pulley combination out of square. Apologies if my memory is playing tricks...
              Dave

              Comment


              • #8
                Quantum luff line checks

                Dave,

                Interesting point. I didn't know about that as my plane has the single pulley. Perhaps a call to P+M might sort that one out Chris?

                Best regards,

                Bob Hood
                XL's forever! Well, one of them anyway. It's all I can afford, not to mention the Raven and the Mini-Max. Oh, and I almost forgot the Spectrum as well :-)

                Comment


                • #9
                  Quantum luff line checks

                  Yes, mine has 3 pulleys and is rigged as you described Dave, the problem I have is that the pulley block catches on the top wire wearing away the plastic protection, Henry Long had same config and rang P & M with same conundrum, the thread is still on this forum, they advised the long lines go on outer pulley, middle on middle and short on inner etc,

                  Chris

                  Comment


                  • #10
                    Quantum luff line checks

                    Hi guys, I recently put new luff lines on a Q2 and the outer one was causing the pulley block to sit off-square as Dave said and was forcing the lines to slip out of the pulley and rub the steel plate, not ideal at all, so I had to rearrange the order to find the best compromise. I will take a note of the order next time at the field.
                    It's a tough but possible job to do on your own if the wing is fully tensioned, but I would recommend removing and de-tention the wing as it's much easier to slip them in and out then.

                    Ok. Inner is on the front pulley, outer is on the middle pulley and middle luff Line is on the rear pulley. Is the only way I could get them to sit any way civilised in the pulleys. Even now looking at it the inner luff line is nearly jumping the pulley.
                    flying is good for you!

                    Comment


                    • #11
                      Quantum luff line checks

                      Hello Gents,

                      I'm looking for some guidance with SB142 concerning applicability to a Quantum please, as I'm a bit confused about it.

                      The SB implies the work has to be carried out by an inspector before next flight, as it seems he is meant to sign for the work. My problem is that I'm not located at at an airfield or anywhere near where a flexwing inspector is based. I had some issues getting the permit renewed and so if I have to get an inspector to do the work (and repeat it every 50 hrs according to the SB requirements) it's going to cost me a goodly sum each time. Is it correct that the work has to be done by an inspector initially and each subsequent 50 hr check?

                      It has been mentioned by Bob Hood above that if the damage is minor, the heatshrink sleeving can be fitted. However, what would be classed as minor damage? Slight polishing of or flattening of the webbing? Slight "fluffing" of the strands? One broken strand (of possibly 150 in total, so loss of less than 1% strength)? Again, the SB doesn't give any guidance. I don't wish to cast any questions over anyones competence or integrity, but what is the opinion of an inspector please? One other point which doesn't seem to be covered by the SB is that the work is on a flying control system and so independent checks should be carried out after completion.

                      In respect of replacing the webbing (the backup cord temporary fix is just that - temporary), this is major and expensive work, so will P&M do it under any sort of warranty or goodwill scheme?

                      I await comments from learned members please.

                      Thanks,

                      Frank.

                      Comment


                      • #12
                        Quantum luff line checks

                        Frank,

                        As far as I understood SB 142 it initially is an owner/operator check to be carried out, then every 50hrs but checked by an inspector on its permit renewal, which I would have thought that sort of thing would have been part of their inspection anyhow,

                        My wing is less than 200hrs old so isn't included but I'm checking it as "best practice preventive" rather than waiting another 100hrs to see if any wear has occurred,

                        I'm not an inspector but fairly sure I've read and understood it correctly, I'm sure someone will put me straight if this isn't the case,

                        Chris

                        Comment


                        • #13
                          Quantum luff line checks

                          Hi Chris,

                          Thanks for your comments.

                          The SB clearly states in section 3 that the technical log must be signed "Service bulletin SB142 carried out" by a qualified inspector. In my view, that means the whole process and there doesn't seem to be any get-out. However, I have seen clarification in another post regarding an SB that actually the "Inspector" can be someone who inspects, rather than a BMAA registered Inspector.

                          In my humble opinion, many of these types of documents (SB's MPD's etc) are quite loosely written and leave a lot of things open to individual interpretation. That shouldn't be the case for such important matters. As it happens, I used to write such documents for a living in a former life.

                          OK about checking your wing with less than 200 Hrs - That makes sense to me too.

                          Regards,

                          Frank.

                          Comment


                          • #14
                            Quantum luff line checks

                            Hi Frank. It says nothing about a qualified inspector having to do the work. He just needs to sign the logbook. It's where the inverted commas are placed that's important!
                            Might be worth asking the question if you posted him the logbook and a bunch of photos and a video even of the job you did, would he then sign the logbook if he is satisfied that you did it IAW the bulletin??
                            flying is good for you!

                            Comment


                            • #15
                              Quantum luff line checks

                              Hello Henry,

                              Thank you for your comments.

                              Yes, it does make a difference where the inverted commas are placed, but I'm trying to get clarification from P&M at the moment. I'll post the response I get on here.

                              Best regards,

                              Frank.

                              Comment

                              Working...
                              X