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John R

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About John R

  • Birthday 03/09/1941

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  • Gender
    Male
  • Location
    West Sussex
  • Interests
    Jets - Experimentals and prototypes

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  1. Paul Bradley did a review of the Xtrakit version https://ipmsusa.org/reviews/Kits/Aircraft/xtrakits_72_sea-vixen/xtrakits_72_sea-vixen.htm Somewhere else he did a 'WIP' and showed a finished build. My own experience with it was an unhappy one. Instead of ending on the shelf of doom it ended up in the dustbin. John
  2. Thank you. I have edited the main post to show a comparison between FR5 and F7 Apparently they did not use the dogtooth on the F2 because it was not the complete answer. It was later found that the CG needed to be moved forward. John
  3. My interest is in prototypes and as the Supermarine 541 was allegedly the prototype Swift this started me wondering if an Alleycat F1 conversion kit that I had could be used to make a 541 instead of an F1. The subsequent investigation resulted in some confusion before I worked out what was going on. It started when I found that the wing supplied by Alleycat had a greater chord than the 541 wing shown in Barrie Hygate’s book of British Experimental Jets. As there were two 541 a/c and the second was much more like the F1 than the first and as Hygate did not give a drawing of the second I wondered if the second had a different wing. Digging into the history of the Swift wing shape produced the following summary The 541 had the 535 wing with streamwise wingtips The F1 had the same wing as the 541 but some sources say that it was moved rearwards. The F2 had the wing root extended forwards giving a kink in the leading edge leading to pitch-up problems. One solution tried was a ‘dog-tooth’ extension to the outer section but was not adopted for the F2. F3 as F2 F4 had the ‘dog-tooth’ but confusingly the prototype F4, WK198, used for the World Speed Record did not have it. FR5 and FR7 had the ‘dog-tooth’ It has been told that the ‘dog-tooth’ on the F4 and subsequent versions was created not by extending the chord of the outer section but by cutting back the inboard section. This always seemed unlikely to me but until now I accepted it. I now believe that for the F4, FR5 and F7 the chord of the outboard section was increased and AlleyCat got it wrong in simply producing a copy of the FR5 wing with the leading edge between the root and the dog-tooth filled in. This resulted in the increase in chord of the AlleyCat wing. Odd because AlleyCat produced an F2/F4 wing that I think was OK so it was only necessary to remove the LE extension of the F2. There is a description of how the dog-tooth was created by increasing the chord of the outer wing in Guy Ellis’s book ‘WK275’ given by someone who was present when it was first done. Finally a warning. The drawing of the 541 in Hygate’s book is not quite 1/72 scale. The wingspan is given as 32’ 4” which in 1/72 scales as 5.4” or 13.7cm whereas span on the drawing is 13.25 cm/ 5.25”. Rivet counters beware, it’s 1/74! A comparison between the wing of the Airfix FR5 and the tip extension of the F7
  4. Clearly the work of someone with a serious mental problem. Bill, you should see someone about it. Happy New Year John
  5. Sorry Steve, I meant to say the Hunter's BIG brother (not bit)
  6. Looks like the Hunter's bit brother! Nice one, Steve John
  7. Mediocre? In what way - fit, accuracy or lack of details? It looks like you did a good job anyway John
  8. Curse you Ed! That's another one on my bucket list that you have beaten me to. Still this time you have paved the way. Keep up the good work John
  9. Nice work. When I built the Hi Planes version many years ago my wife thought that it was 'sweet' John
  10. I have been trying for ages to work out how to build one of these. Whether to work forward from an Attacker or backwards from a Swift without success. Well done on finding the way. John
  11. I bet that many, when they first saw this, would think that it was a "what if". I felt much the same way when I saw a picture of the real thing. I didn't know that the Iranians possessed the design and manufactring capability to do it. Nice work and thanks for showing it. It is something I would liked to have done. John
  12. Nice work. As the builder of several Modelsvit kits I can appreciate the 'challenges' that you faced. John
  13. In some ways I feel guilty about putting people off trying to build it but I thought it wise to highlight the problems so people were warned what to expect before buying one or starting one they had. If you do start yours think very carefully about what the end result should look like when assembling the intakes. There may be a better way of getting the outer wing section to match that of the centre by using a spacer between the leading edges of the outer wing halves. I couldn't have done this because I had already glued them together when I found the problem. John
  14. Thanks Chris. I feel an idiot for realising. It's my age you know... John
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