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Recent content by JQCF1

  1. JQCF1

    European Blind Rivets

    Hi all, Developing a wing leading edge skin repair for a Czech Blanik L-23 glider and need to use CherryMax or equivalent rivets in a couple of locations. Blanik repair manual says "If the area is inaccessible from the inside...use special rivets with pins per the Standard 1646S49 (or 1646549...
  2. JQCF1

    Opto-Mechanical design

    Drawoh, Please do your homework.....In FAA speak a Designated Airworthiness Representative is a DAR and a DER is a Designated Engineering Representative. Typically neither has much to do with any revolutions. Primarily, the DAR is involved with Airworthiness issues and a DER with Engineering...
  3. JQCF1

    Opto-Mechanical design

    Drawoh, You cited the problem OK but unless I'm confused about the situation I think you need DER help not DAR help, Right?
  4. JQCF1

    Parachute Models

    Michael, We did the testing of the full-scale full deployed Vortex Ring chute in the settling chamber of the UAC main subsonic tunnel. The 18 ft octagonal test section was too small!! Neat project; I have a test report around here somewhere. Good luck, John Cragin
  5. JQCF1

    Parachute Models

    Michael Orenstein Speaking about ancient history of parachutes...I was involved in full-scale wind tunnel tests at United Aircraft Corp (Now United Technology)back in the 60's of a Vortex Ring parachute being developed hy Pioneer Parachute, Manchester, CT. Designed as I reccall by a Dave...
  6. JQCF1

    Material Properties 20 mil PVC Film Needed

    Hi All, I need material properties, primarily tensile strength, on 20 mil thick pvc film used for boat and tent windows, seat covers etc. This material is described as double polished, optically clear and cold crack resistant to -40 F Can anybody help with tensile strength details? Thanks JQCF1
  7. JQCF1

    wear rivets

    Kontik99, I'd tell the ASI to go pound sand if he came up with that mandate!! Maybe the AD dimple was just filled with paint or Bondo?? What then? You'd do more damage replacing many 402 rivets than just leaving them alone. JQC DER/DAR
  8. JQCF1

    fitting analysis

    GBor Your finagle factor of 1.15 is right out of 23.625 and probably Part 25 and 27 as well. The problem is the definition of "fitting"?? I understand a seat belt fitting that goes between the nylon webbing and the seat. But what if the manufacturer identifies a widget as a "bracket" and the...
  9. JQCF1

    Lightening holes??

    Hi all. When asked why the T-18 doesn't have more lightening holes, John Thorp's reply typically was "Because they weaken the stucture faster than they lighten it!! Agree?? John Q.
  10. JQCF1

    Definition of a Metallurgist

    This string reminds me of an old saying in the post-WWII days by Theodore Von Karman a famous low speed aerodymacist from the Netherlands I believe. A typical aerodynamacist will define his problem condtions before proceding and will say "Assume the aircraft weighs 2000#, has xxx ft squared...
  11. JQCF1

    Vintage Volpar dwgs??

    I'm chasing details of an STC SA3458WE that refs Volpar drawing list 5300, rev B of 6/28/77. Can anybody help in my search? To my recollection Volpar is long in the history books. Any source of Volpar dwgs? Thanks for any comments. John Q.
  12. JQCF1

    Interference affects on Pitot probe

    Hi Berkshire, We must be on the same frequency!! I also found Space Age Control (via Google) and some of their components look quite doable. Neat website. I forwarded their URL to my client and we'll see what he wants to do. He's holding the purse strings. I'm also proposing a Pitot probe at...
  13. JQCF1

    Interference affects on Pitot probe

    RB and Berkshire. Neat ideas. I like the trailing probe. This a/c is pressurized. How do we trail the p/s probe? ie, How do we release it to trail after take-off and retrieve it before landing? I've never used this scheme but it sounds like it will work. Are there kits available or do we...
  14. JQCF1

    Interference affects on Pitot probe

    Hi Rb and Field Team, We do not propose changing the pitot probes, just the radome configuration; and that not drastically. The static ports are on the aft fuselage and will not be disturbed. This TC'd a/c is currently operating on a Special/Experimental A/W cert (8130-7) so we can play games...
  15. JQCF1

    Interference affects on Pitot probe

    Hi all, We are considering minor exterior (aerodynamic) changes to a nose radome. Any leads as to how this will/might affect the pitot (total pressure) probe that is slightly aft of the radome. We are talking Vne appx 250kts. Any reasonable measure of probe standoff distance to fuselage...

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