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  • Originally posted by Savoia View Post

    Elipix, would you be able to dig up any more info on this history of this patent? I wonder if a diagram was submitted with this?


    FENESTRON

    G & J Weir, of Cathcart, Glasgow patented their design for a shrouded tail rotor concept in May 1943. It was designed by C.G Pullin and the patent was held by Cierva who Weir were working in collabration with. The patent no can be seen on the drawings. This helicopter as far as I know never flew.


    572,417. Helicopters. WEIR, Ltd., G. & J., and PULLIN, C. G. May 24, 1943, No. 8186. [Class 4] A helicopter of the kind having a single tiltable rotor with articulated blades is provided with an auxiliary rotor, for compensating the torque reaction, arranged within a normally transverse duct at the rear of the aircraft. The duct may have adjustable parts to vary the direction of the reaction on the helicopter, or the whole duct may be rotatable about a vertical axis independently of or with the rotor. In the latter case, the duct and rotor may be set fore and art of the machine to assist propulsion during high-speed horizontal flight, and steering effected by adjustment of the duct about its vertical axis. In one form, the auxiliary rotor comprises a hub 42, with blades 43 variable and reversible in pitch, which is driven from the main engine through shafts 37, 40 and gear-boxes 39, 41. The rotor is enclosed by a duct 44, 45, in two parts of which the rear part 45 is adjustable about a vertical axis by worm gear 50, 51 and sprocketwheel 53 controllable through cables 54 from the pilot's cockpit. The blades 43 have eccentric pins 56 engaged by a groove in a striker 57 movable by a rack 59 and worm 60 controlled through a sprocket 61 and cables 62 from the rudder bar. Branch cables 64 are connected to a rudder 24. The pitch change gear is enclosed by a fairing 47a having radiating blades 48 secured to the fixed part 44 of the duct. A fairing 47b encloses the gear-box 41. In another form, the blades 43 are fixed to the hub and the blades 48 are adjustable to control the flow through the duct by mechanism similar to that shown for adjusting the blades 43 in Figs. 2 and 3. In these two forms the part 45 of the duct is mounted on a spherical seating and provision may be made for tilting the part 45 in a vertical plane. In another form, the whole of the duct is adjustable about a vertical axis, together with the motor, the speed of which is controlled by a change-speed gear in the gear-box 39 under the control of the pilot.

    There was another patent application in the USA in 1946 by John G Lee



    Now to the French FENESTRON, designed by Paul Fabre from Aix en Provence who chose the name Fenestrou - a Provencal meaning for small window. So it seems Weir/Cierva may have been the first to patent this design. Where does that leave the Fenestron, is it just the name that has a trademark ? Or do SUD Aviation owe it all to G & J Weir ?

    Another concept that Weir had developed well ahead of its time was a Notar system ! This they did develop and flew a slightly bigger version.



    โ€‹Scotland seems to be very much the birthplace of the powered helicopter, the Denny Mumford Helicopter and now we find they may also be responsible for the Shrouded tail rotor !
    Last edited by Helipixman; 25th August 2020, 19:29.

    Comment


    • Savoia
      Savoia commented
      Editing a comment
      Now you know why we call Elipix .. Eliโญ

    • Zishelix
      Zishelix commented
      Editing a comment
      Well done, Helipix!



  • G-VOIP Change of Ownership

    G-VOIP Gazelle HT.3 (1792), changed ownership to J.H. Coventry, London, on 04-Aug-2020.

    Comment


    • Savoia
      Savoia commented
      Editing a comment
      Grazie mille Jos! ๐Ÿ‘

    • Zishelix
      Zishelix commented
      Editing a comment
      Thanks Jos for always freshly info regarding Gaz's ownership!



  • SA341B XW847 (WA1011) as seen at Manchester Barton on 10th November 2017 (Photo by Craig Duffy)




    SA341D XZ936 (WA1743) as seen at RAF Fairford on 14th July 1985

    Comment


    • LE FENESTRON: A LESSER TOLD STORY

      Thanks to the research efforts of Avia member Elipix (also known as EliStar), a slightly different angle as to the history of the Fenestron has come to light.

      Since the 1960's the development of the Fenestron has been regarded by many throughout the rotary-wing community as being an exclusively French concept invented by Renรฉ Mouille, while it would appear as if neither of these assumptions are accurate.

      It seems instead that Paul Fabre working under Renรฉ Mouille was the one who developed Sud Aviationโ€™s interpretation of an already existing โ€˜fan-in-tailโ€™ concept, and it was also Paul Fabre who gave the Fenestron its name, for as we read:

      Born in Aix-en-Provence and fiercely loyal to his roots, Paul Fabre chose the name โ€˜fenestrouโ€™, a Provencal word meaning โ€˜small round windowโ€™, to designate his shrouded rotor invention. However, Franรงois Legrand, head of the Design Office at the time, refused to accept this deviation from the French language, and Fabreโ€™s Fenestrou soon became the โ€˜Fenestronโ€™.

      Of Paul Fabre, the Airbus-owned publication โ€˜Rotorโ€™ writes:

      In the 1960โ€™s, the fragility of conventional tail rotors prompted research into reducing sensitivity to the environment. Paul Fabre, head of the Sud Aviation Aerodynamics department and specialist in seaplanes, under the supervision of head engineer Renรฉ Mouille in the Design Office, designed a fan-in-fin shrouded rotor for the SA340.

      - Monique Colognes (Rotor, September 2007)

      While UK Aviation news wrote:

      The Fenestron is now a familiar sight on helicopters produced by companies like Aรฉrospatiale, Sud-aviation and later Airbus, but before 1968 the safety-improving device didnโ€™t exist; now we look back at 50 years since the invention of the Fenestron.

      Invented by Paul Fabre and Renรฉ Mouille the shrouded tail rotor was initially developed to provide safety for workers. It operates like a ducted fan and by doing so it reduces tip vortex losses whilst shielding the tail rotor from damage making it ideal for operating in complex operational environments such as high-voltage power lines or in confined areas.

      - Nick Harding (UK Aviation News, 13th April 2018)

      The only trouble is, the Fenestron (or ducted tail rotor) did exist before 1968, at least in terms of a concept with drawings.

      History reveals a somewhat different story behind the origins of what was to become the Fenestron. Cyril Pullin was a British inventor and motorcycle racer who in 1932 joined G & J Weir Ltd, an engineering firm founded by brothers George and James Weir, the latter being an early Scottish aviator and successful industrialist who financed Juan de la Cierva's development of the autogyro.

      Pullin joined Weirโ€™s aircraft development workshop in Glasgow as chief designer, initially developing single-place autogyros before moving on to small helicopter designs. In the early 1940โ€™s he began working on the development of a helicopter design which incorporated the use of a ducted-fan tail-rotor. This design was registered by G & J Weir with the British patent office (patent no. 572417) on 24th May 1943.

      The patent notes describe the following design:

      A helicopter of the kind having a single tiltable rotor with articulated blades is provided with an auxiliary rotor [tail-rotor] for compensating the torque reaction, arranged within a normally transverse duct at the rear of the aircraft.

      The duct [ducted tail-rotor] may have adjustable parts to vary the direction of the reaction on the helicopter. The auxiliary rotor [tail rotor] comprises a hub with blades both variable and reversible in pitch, which are driven from the main engine through shafts and gear-boxes. The rotor is enclosed by a duct.

      This ducted tail-rotor invented by Cyril Pullen therefore seems to be the true origin of the present day fenestron, for that the present-day fenestron is a ducted tail-rotor possessing variable pitch blades is without question.


      Cyril Pullen's ducted-fan tail-rotor, the 1943 precursor to the Fenestron


      Cyril Pullin, the true inventor of the fenestron, seated upon a Rudge Multi motorcycle on Isle of Man in 1914

      In 2018 Airbus celebrated the fiftieth anniversary of the first flight with a Fenestron, with their press release reading as follows:

      On the 12th of April 1968, the first Fenestron, invented by Paul Fabre and Renรฉ Mouille, took to the skies on the second prototype of the Gazelle. It has since become emblematic of Sud Aviation, Aerospatiale, Eurocopter and now Airbus helicopters with the H160 carrying this sound-reducing, safety-enhancing technology into the next generation of rotorcraft.

      The idea behind shrouding the tail rotor was initially developed to provide additional safeguards for workers on the ground but also to protect the tail rotor in forward flight and in complicated operational environments, such as working around high-voltage power lines. Sound reduction benefits followed after much research and optimisation from one generation of the Fenestron to the next.

      Originally called the โ€œFenestrouโ€, which is Provenรงal for โ€œlittle windowโ€, the term evolved into the renowned Fenestron. It was first certified on the Gazelle in 1972 and then subsequently integrated into the first single-engine Dauphin prototype, whose first flight was in June 1972.

      โ€“ Airbus press release (Marignane, 12th April 2018)

      But again, the Fenestron wasnโ€™t in fact invented by Paul Fabre and Renรฉ Mouille, but by a British inventor and motorcycle racer while working in Scotland some twenty-five years before the Fenestron first flew!

      This may account for the use of a fan-in-tail (Fenestron) on types such as the Cabri and Marenco/Kopter SH09 in that Sud Aviation may not have been able to claim exclusive rights to the concept, because they didn't invent it.

      According to Elipixโ€™s research it isnโ€™t just the origins of the Fenestron which have been largely forgotten, but also that relating to the development of the NOTAR which too seems to have been conceived by Cyril Pullin.

      ~ ~ ~

      We are posting this on our FB page see here. Please re-post this on your FB page if you are able, as we are keen to receive feedback concerning this history, especially should anyone have any further light to shed on this matter.



      Comment


      • Helipixman
        Helipixman commented
        Editing a comment
        Yes the Weir patent has expired, and if they only last 20 years would have expired in 1963. Can anyone use the fan in fin concept now ? as in the new Hill HX50 ?

      • Fabrice
        Fabrice commented
        Editing a comment
        Indeed, the shrouded tail rotor concept is much older than the Fenestron designโ€ฆ and even as the ones patented by Pullin in Scotland and Lee in the USA.
        Two German brothers, Fritz and Wilhelm von Achenbach, draw a giant helicopter project (powered by a boiler !), which, for the very first time, incorporated a tail rotor, enclosed in a large fin, for torque reaction control. That was inโ€ฆ1874 ! In 1897, another German, B. R. Beenan, patented another helicopter project, once again equipped with a ducted tail rotor. Noteworthy for this project, apart from the tail rotor, is the fact that, for the first time, a main rotor collective pitch control was described.
        But a Fenestron is not only a ducted tail rotor.
        With a ยซ simple ยป ducted tail rotor, you achieve two major improvements :
        -increased safety for ramp personnel,
        -better aerodynamic efficiency, caused by the suppression of the drag from a ยซ classical ยป (unshrouded) tail rotor.
        But with a Fenestron, the tail rotor is fully enclosed in a large vertical fin, whose special profile allows to take on charge all the torque reaction force when the forward speed is important enough. In hovering flight, a Fenestron demands a bit more power than a ยซ classical ยป tail rotor (especially with crosswind : every Gazelle pilot will understand what I meanโ€ฆ), but from a given speed, the torque effect is entirely compensated by the fin-induced side force, then the tail rotor uses virtually zero power (apart when the pilot gives yaw inputs), and all the power is then available for the main rotor. In case of loss of engine power, as long as the speed is kept above a given value, thereโ€™s no handling difficulty. This is a major feature from the Fenestron, which was imaginated from the very beginning of the design.
        As a conclusion, there is no evidence that either Mouille or Fabre had any knowledge of the Weir or Lee patentsโ€ฆ but it wouldnโ€™t be the first time that a given concept is imaginated from scratch by different engineers, living in different places at different periods (the ramjet engine is a good example).

      • Zishelix
        Zishelix commented
        Editing a comment
        It would be interesting to read what's said about history of the shrouded tail rotor solution in the introduction section of this scientific article https://www.ingentaconnect.com/conte...00004/art00003



    • SA342L 241 (cn.1854) as seen at RAF Cottesmore on 29th July 2001 (Photo by Rob Schleiffert)




      SA342M from 3RHC departing Charleville-Mรฉziรจres on 26th August 2020

      Comment



      • Elipix wrote: Can anyone use the fan in fin concept now as in the new Hill HX50?
        Kopter are certainly using it and it has flown on both the Ka-60 and Kawasaki OH-1 since the late 90's. I'm not sufficiently 'au fait' with design laws, but there are certain design rights which are automatically apply to proprietary products. However, my assumption is that these are weakened when a product is based on a non-original design, as is the case with the Fenestron.

        Returning to the HX50, herewith a comparison with a fifteen-year-old humorous concept drawing for a 'Bell 351'.



        Comment


        • Helipixman
          Helipixman commented
          Editing a comment
          Some similarities there... which one would you have ? I do like the sleek looks of the HX50, but Bell have a proven track record ! Shame they did not build it. Good luck to Hill helicopters

        • Savoia
          Savoia commented
          Editing a comment
          They both look neat, but handling would be a factor that would influence me and if for commercial use then performance. I have some hours on the MD530F which I thoroughly enjoyed. Being able to comfortably pull out of a confined area with 2-3 pax with plenty of torque and temp to spare combined with crisp handling was a joy.



      • SA341G G-BXJK (cn.1417) as seen at Thruxton Aerodrome in the late 90's (Photo by Michael Rice)




        SA342M F-MGEG panel

        Comment


        • Savoia
          Savoia commented
          Editing a comment
          Grazie Fabrizio! ๐Ÿ‘

          Can you please explain what the '7 alpha' alarm?

          Also, the last 30 342L1's were these all for the same customer and do you know which one?

        • Fabrice
          Fabrice commented
          Editing a comment
          '7 alpha' is how the alarm panel is commonly referred to in the ALAT;I have no idea why, perhaps it is linked with the position it occupies on the instrument panel...

          The 30 SA 342L1 were originally built for an export customer, but were eventually embargoed and taken over by the ALAT. I'm not sure about the original destination, it could have been Iraq but this is pure assumption...

        • Savoia
          Savoia commented
          Editing a comment
          Grazie mille Fabrizio! ๐Ÿ‘



      • YU-HPZ Engine Failure and Boom Strike in Serbia

        Hi everybody!

        Looks like YU-HPZ was involved in an accident on July 31st.

        Smoke was reported in the cabin then suddenly the turbine stopped forcing the pilot to make an autorotative landing.

        Sadly the main rotor blade tips contacted the tail boom during the landing, but the pilot escaped unhurt.

        Let's hope good old #1473 will fly again.

        Comment


        • Helipixman
          Helipixman commented
          Editing a comment
          Glad to see you back Zis ! You have a lot to catch up with.

          Sad news about YU-HPZ boom etc can be replaced, glad to see all escaped unharmed. Wonder where it happened, one of the flight trackers has it as last being in either Austria or Bratislava ?

        • Zishelix
          Zishelix commented
          Editing a comment
          Thanks, trying to get in the saddle again

          The accident happened in Serbia, in the capital Belgrade suburb.

        • Savoia
          Savoia commented
          Editing a comment
          Welcome back Zis!

          Thank you for this info, much appreciated.

          Thankfully no one seems to have been injured and for which we are grateful.




      • E7-VDH Impounded

        SA341H E7-VDH (c/n 060) was impounded last month by Bosnian police. Allegedly, the owner and associates, among other stuff, were charged to provide helicopter services they weren't licensed for.

        Comment


        • Savoia
          Savoia commented
          Editing a comment
          Grazie Zis. ๐Ÿ‘ Let's hope they get it sorted out.



      • SA342L's as seen at Rayak Air Base in Lebanon in August 2020




        SA341B as seen aboard HMS Illustrious in Portsmouth on 24th August 2001 (Photo by Javier Iturbe)

        Comment




        • G-ZZEL Repainted

          G-ZZEL has had a repaint ! Interesting where they have painted a Gazelle on the engine cowling.

          Photo with thanks to Dan Savident.



          And another angle .. SA341B G-ZZEL sn. WA1152 at Pembrey Airport in Carmarthenshire, Wales on 29th August 2020 and with thanks to Eiona Roberts for this photo.

          Last edited by Helipixman; 30th August 2020, 20:18.

          Comment


          • Savoia
            Savoia commented
            Editing a comment
            Well spotted Zis! ๐Ÿ‘

            It seems as if the boys at Bourne Park may have developed some 'home grown' fairings in similar fashion to those developed by the team from SA34X at Wonderboom in South Africa.

            These ones look quite different.

          • Zishelix
            Zishelix commented
            Editing a comment
            Definitely not a standard skid fairings


          • xbdt
            xbdt commented
            Editing a comment
            The purpose of a skid fairing is to make it look nice but also (primary) to gain airspeed. A well designed is the original one (teardrop shape) so the drag onto the skid is minimal.

        • XZ319

          WA341B XZ319/S #1610 at Abingdon in September 16th, 1978. (Photo: Alex Christie)

          Comment




          • SA342M HA-HSG (cn.3615) as seen at Dunchurch in Warwickshire on 30th August 2020 (Photo by Martin Plaskitt)

            Below: The Crabtree Warrior arriving at the Tanks, Trucks & Firepower Show at Dunchurch in Warwickshire on 30th August 2020





            SA341G(S) YU-HHH (cn.1307) as seen at Stapleford on 15th August 2020 (Photo by David Moth)

            Gaz Memorabilia

            Currently For Sale
            • RAF Aircrew Manual and Operating Data Manual for the Gazelle (all versions, AH Mk 1, HT Mk 2, and HT Mk 3), AP 101C-0901 to 0903-15 and 16, 1st edition dated March 1974 with approx. 275 pages
            • Manufacturerโ€™s Flight Manual for the SA341G Gazelle, dated December 1974 with approx. 264 pages
            • Manufacturerโ€™s colour brochure for the Gazelle dated April 1970 with approx. 26 pages


            https://www.flight-manuals-online.co...tland-gazelle/




            ZB689 departing Bray in Ireland in 2014


            Fenestron History

            Fabrice wrote: Indeed, the shrouded tail rotor concept is much older than the Fenestron designโ€ฆ and even as the ones patented by Pullin in Scotland and Lee in the USA.

            Two German brothers, Fritz and Wilhelm von Achenbach, draw a giant helicopter project (powered by a boiler!) which, for the very first time incorporated a tail rotor enclosed in a large fin for torque reaction control. That was inโ€ฆ1874 !

            In 1897, another German, B. R. Beenan, patented another helicopter project, once again equipped with a ducted tail rotor. Noteworthy for this project, apart from the tail rotor, is the fact that for the first time a main rotor collective pitch control was described.
            Are you saying I need to make another T-shirt .. this time saying that the concept of the Fenestron comes from Germany?

            Thanks for this very interesting info Fabrizio!

            I should love to see a diagram of a steam-powered Fenestron!

            Comment


          • C/n for YU-HHH (see previous post) is 1307, ex G-OLDH.

            Comment


            • Savoia
              Savoia commented
              Editing a comment
              Grazie Jos! ๐Ÿ‘ Not quite sure what happened there!



          • Cypriot SA342L1 '355' c/n 2199 on the ramp at Lakatamia AB probably in early 1990s. (Photo: R. Francillon)

            Comment


            • Savoia
              Savoia commented
              Editing a comment
              Very nice Zis! ๐Ÿ‘



          • SA342M1 F-MGFB 4233 (cn.2233) as seen at Poznaล„ Krzesiny Airport in Poland on 17th May 2018 (Photo by Mariusz Woลบniak)


            SA342M F-MCKW (cn.3511/1511) as seen in Kosovo in 1999 (Photo by Oliver Cousin)




            SA341C G-SWWM (WA1033) as seen at Silverstone in 1998 (Photo by Chris Lane)




            Thanks to the Avia team (notably Elipix and Fabrizio) we now have a clearer understanding of the origins of the conceptual design of what is today the fenestron. It would seem that this emerged as a concept first developed by the German brothers Fritz and Wilhelm von Achenbach in a steam-powered helicopter design from 1874. From there a ducted-fan tail-rotor was proposed by the Scottish-based English inventor Cyril Pullin as a patented design in 1943 and in 1968 Paul Fabre developed a fan-in-tail design which he named 'fenestrou' which would go into production as the Gazelle's standard tail-rotor.

            If anyone has any further details as to the origins of the fenestron, please let us know.


            Fritz and Wilhelm von Achenbach's steam-powered fenestron-fitted 1874 design



            So, we owe the origins of the fenestron to two German brothers who imagined the device being driven by steam!

            At least everyone agrees that the helicopter design itself was invented in Italy in 1493!




            Another take on Stefano's arrival at Dunchurch on Sunday


            G-ONNE vs. G-ZZEL Which Paint Scheme Do You Prefer?

            Coming up with an imaginative scheme for a black and white aircraft may not be the easiest of tasks, but of these two designs, which do you prefer. You may either write a comment below or on our FB page.



            Comment


            • Zishelix
              Zishelix commented
              Editing a comment
              Since I'm old fashioned when it comes to Gazelle liveries I'll excuse myself from the voting

            • Helipixman
              Helipixman commented
              Editing a comment
              I agree with Zishelix, both he and I like the original schemes. Some of the new schemes are also ok though.

              We should have some sort of attempt at designing a new scheme just to see what else we could come up with. Anyone got a half decent template for us to try ?

          • Gaz Line Up

            40 British Gazelles lined up in the air at the Middle Wallop Airshow probably back in mid '80s (Photo: Stuart Mitchell)



            Wish I was there at least to hear the sound

            Comment



            • Gazelle Maintenance Manual/Document

              I would love to receive a scanned copy of this document should anyone happen to have this publication.

              Comment




              • SA341H HA-LFN (cn.045) as seen at Nyรญregyhรกza Airport in Hungary on 1st September 2020 (Photo by Peter Csabai)




                SA342L ZU-RHH (cn.1787) as seen at Rand Airport in South Africa on 26th September 2013 (Photo by Bruce Perkins)


                Gazelle flight training with Paramount Aviation Academy
                at Polokwane in South Africa in September 2020



                G-ONNE vs G-ZZEL

                The overwhelming result in the preference of paint schemes from our FB comments was .. G-ONNE.

                The best comment so far was:

                Regarding G-ZZEL, it looks like its been hit by a large black golf ball!



                Additional Facebook Comments Relating to G-ZZEL

                Andy wrote: G-ZZEL has the designator SA-341 painted on the transmission cowling, shouldn't this be WA341?
                Elipix replied: This has always been a sticking point, even the CAA are inconsistant. The early civilian Westland Gazelles had varied construction numbers, some had prefix WA and others didn't. Most of the newer ex-military Westland Gazelles do not show WA.

                As the Westland Gazelles were built under licence I suppose they should be called SA341 but I think all should have a WA prefix on the c/n to show they are Westland built. As an example, the registration document for G-BAGL states it was constructed by Westland Helicopters and SNIAS. It calls the type 'Gazelle SA341 Srs.1'.

                Did Westland build them from scratch or were parts sent across from France? My personal records always show the c/n as WA. and the type SA341. I can see a case for both, calling it SA341 or W341. What does the WA stand for anyway? Westland Aircraft? I think not, they are Westland helicopters, maybe it's Westland/Aerospatiale?
                Sav replied: The Westland-built Gazelles were actually assembled. There was little if anything fabricated by Westland.

                Facebook Comment in Response to YU-HPZ's Boom Strike

                Paul wrote: Just struggling to understand .. you would expect high disc load in an engine off? But if done in final flare it was very lucky not to flip. I would just like to understand so I can learn from the lessons/mistakes of others.


                Sav replied: Sadly, not only boom strikes .. but slicing-off the entire fenestron is not unheard of when it comes to Gazelle engine-off landings. Whether this happens at the final stage of an aggressive flare or through flex in the the blades after a heavy touch-down (the Gazelle blades are extremely 'bendy') I am uncertain .. but will enquire and post the reply on the forum.




                Could one of our Gaz drivers clarify whether these boom strikes occur after a heavy touchdown?

                Comment


                • Zishelix
                  Zishelix commented
                  Editing a comment
                  http://www.aviafora.com/forums/forum...=9830#post9830

                  'Due to the low main rotor inertia and the aft cyclic control stick input,the main rotor blades made contact with the tail boom and severed the structure.'

                • Savoia
                  Savoia commented
                  Editing a comment
                  It seems to me most likely that these strikes on the tailboom are occurring at touchdown or immediately post-touchdown and when such a touchdown is hard. Once the airframe contacts the ground, and if that contact is aggressive, it is going to send a shock load through the fuselage up through the mast and cause the entire disk to bend downwards and if (as you have suggested) there is less energy in the rotor, then the Gazelle's very flexible blades are likely to strike the boom.

                  This is just my assumption though. Would love to hear a more informed opinion.

              • I have a technical question. I am aware that the extended fuselage Gazelles have shorter end plates on the horizontal stabilizers. Is this because the longer fuselage requires less directional stability than the shorter fuselage Gazelles or is there another reason for the shorter end plates?

                Also, a what-if question, what would be the effect of having an extended fuselage Gazelle with the longer end plates? Would it cause any aerodynamic problems? My first thought is why change to a different part (shorter end plates) and added cost, if the original (longer end plates) didn't cause any issues? I imagine the whole reason for switching to shorter end plates is because of some aerodynamic issues. Any information on this would be most appreciated.

                Comment


                • xbdt
                  xbdt commented
                  Editing a comment
                  The small vertical fins are no ballast weights. There is absolutely no reason to put additional stress on the horizontal stabiliser bar or to induce additional vibrations.
                  Ballast weights are normally mounted in the lower boot. Some army gazelles also have an inspection hole on the right side of the lower boot just to check if there are ballast weights installed or not (depending on equipment installed).
                  But why are these fins shorter? I don't know.

                • Zishelix
                  Zishelix commented
                  Editing a comment
                  We're blessed to have Gazelle experts here Always something new to learn. Thanks, XB!

                • goose814
                  goose814 commented
                  Editing a comment
                  I would think that with the cabin being stretched ahead of the main rotor mast, that would cause a shift of the CG towards being slightly more nose heavy, which would require it to have more weight aft of the rotor mast to balance it out. A decrease in the size of the end plates would lessen the weight aft and shift the CG forward even more, so I don't think their purpose is for weight & balance.

                  Savoia, I have seen the photo of the stretched Gazelle with larger end plates. It was posted by xbdt in post #4357 (SA341G c/n 1310 N47300). Like you mentioned, I believe it was a prototype. I'd like to see what it looks like currently.

                  xbdt, when you say lower boot which part are you referring to? I'm not familiar with where that is. Thanks.

                  Zishelix, hello to you too. It's been a while.



              • Gazelle Squadron Gazelles at Pembrey Airfield in Wales on 30th August 2020 (Photo by Robert Griffiths)


                Gazelle Squadron Gazelles practising with Team Raven
                at Pembrey Airfield in Wales on 30th August 2020




                Another take on SA341H HA-LFN (cn.045) as seen at Nyรญregyhรกza Airport in Hungary on 1st September 2020 (Photo by Peter Csabai)

                Comment


                • N341ZL

                  An interesting detail on N341ZL's tail:



                  Comment




                • SA341G(S) G-BKLV (cn.1307) as seen at Gloucester Staverton on 21st November 1983 (Photo by Keith Wilson)


                  YU-HOT


                  SA341G(S) YU-HOT (cn.1390) as seen at Nikola Tesla Airport in Belgrade, Serbia on 3rd September 2020




                  New Preta Gazelle model

                  This is a fully flying mini-Gaz.

                  Preta Models.

                  Comment




                • SA341F2 F-MGQW as seen at Phalsbourg-Bourscheid Air Base on 13th September 2009 (Photo by Paul Schaller)




                  Gazelle Squadron Gazelles at Pembrey Airfield in Wales on 29th August 2020




                  SA341B ZB690 (WA2003) as seen overhead Ballykelly in Northern Ireland on 3rd September 2020 (Photo by John Purvis)

                  John writes: "Airborne about 3 or 4 times per week for short runs over neighbouring fields, possibly operating out of the old RAF Ballykelly airfield. Registration ZB690 is listed as being in a museum in Yeovilton so Im not sure who owns this Gazelle - trying to find out a bit more."

                  Elipix, are you able to shed some light on this matter?

                  Comment


                  • Helipixman
                    Helipixman commented
                    Editing a comment
                    My records show that ZB690 is an active AAC 665 Squadron Gazelle based at Aldergrove, it was recently at Standard Aero, Fleetlands for servicing and have seen reports of it operating with 665 Sqn in late August 2020 so assume it has been re-delivered back to Aldergrove.

                  • Savoia
                    Savoia commented
                    Editing a comment
                    Grazie mille Eliโญ

                • XX449

                  WA341B c/n 1443 XX449/J seen with invasion stripes at Detmold Airfield, Germany in October 1991



                  Now with QinetiQ http://www.aviafora.com/forums/forum...=8540#post8540

                  Comment


                  • Savoia
                    Savoia commented
                    Editing a comment
                    Zis wrote: ๐—ช๐—ต๐—ถ๐—ฐ๐—ต ๐—ผ๐˜๐—ต๐—ฒ๐—ฟ ๐˜๐˜„๐—ผ ๐—š๐—ฎ๐˜‡๐—ฒ๐—น๐—น๐—ฒ๐˜€ ๐—ฑ๐—ถ๐—ฑ ๐—ค๐—ถ๐—ป๐—ฒ๐˜๐—ถ๐—ค ๐˜€๐—ฒ๐—น๐—น ๐—ฏ๐—ฒ๐˜€๐—ถ๐—ฑ๐—ฒ ๐—ซ๐—ญ๐Ÿต๐Ÿฏ๐Ÿต & ๐—ซ๐—ซ๐Ÿฐ๐Ÿฐ๐Ÿต?

                    Eliโญ to the rescue!

                  • Fabrice
                    Fabrice commented
                    Editing a comment
                    Which other two Gazelles did QinetiQ sell beside XZ939 & XX449?
                    My guess would be ZB625 and XX453.

                  • Zishelix
                    Zishelix commented
                    Editing a comment
                    Merci beaucoup, Fabrice!



                • SA341B ZB674 (WA1967) NFI


                  SA341B ZB689 (WA2002) as seen at Bray in Co. Wicklow in Eire on 20th July 2014




                  SA341G RA-07822 (cn.1073) as seen at Oreshkovo Airfield in Kaluga, Russia on 5th September 2020

                  Below: RA-07822 flying in Kaluga, Russia on 5th September 2020








                  The Wooden Model Co. have three mahogany Gazelles remaining in stock.


                  G-BAGJ Over London

                  A photo of G-BAGJ over Buckingham Palace is currently up for grabs. If one of our UK members or readers would like to bid on this and then send a scanned copy to: aviafora1@gmail.com we would be most grateful.

                  Comment


                  • Helipixman
                    Helipixman commented
                    Editing a comment
                    Are you sure it's 2-GAZL ? That was cancelled and became RA-07822 ? Unless you know something and it's been re-registered ?

                  • Savoia
                    Savoia commented
                    Editing a comment
                    Bravo Elipix! My bad, should be RA-07822, grazie.

                • SA341F c/n 1180 airframe preserved at Phalsbourg AB, seen in July 2017 (Photo: Neil Williams)

                  Comment




                  • NTSB Report on N9334W

                    NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.

                    The pilot reported that, prior to departure, he performed a preflight inspection with guidance from one of the helicopter's owners over the telephone. He determined that "everything was normal." As he prepared for startup, he was unable to close the helicopter's cabin door. He discussed this with the owner, and then removed the door and secured it in the rear of the helicopter.

                    Upon lifting to a 3-foot hover, the helicopter began to turn left and he was unable to correct the turn with right pedal input. He lowered the collective, and as the helicopter touched town, it "did a hovering auto bounce with slight movement to the right and forward and came to a stop."

                    The pilot called the owner to discuss what occurred and subsequently performed two test hovers. He checked the pedals and controls, and the helicopter performed normally.

                    The pilot then flew to the first of two intermediate destinations, and the helicopter performed normally with no abnormal vibrations or noises. He picked up a passenger without shutting down the helicopter, and proceeded to the next intermediate destination where he shut-down the helicopter to refuel. During a walkaround at this stop, the pilot noticed that part of the horizontal stabilizer was "chipped off." The fueler reported to the pilot that he had previously seen the helicopter make several "scary hard landings" during previous flights. The pilot and passenger then flew to the final destination without incident.

                    Subsequent examination of the helicopter revealed substantial damage to the fuselage consistent with a hard landing. The pilot at the time of the hard landing and the date and time of occurrence was not determined.
                    https://www.ntsb.gov/_layouts/ntsb.a...13X74513&key=1


                    Report on N342J

                    On June 21, 2020, about 1330 Pacific daylight time, an Aerospatiale SA-324J helicopter, N342J, was destroyed when it was involved in an accident at the Minden-Tahoe Airport (MEV), Minden, Nevada. The pilot and passenger received minor injuries. The helicopter was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight.

                    According to the pilot, he had filled the helicopter with fuel and operated the helicopter for about 1 hour 15 minutes. During the flight the pilot noticed the engine exhaust gas temperature at about 50 higher than usual. During the approach, on the return flight to the airport, he descended to about 50 ft above ground level (agl) and continued to his intended touchdown point. While over a level area, at about 25 ft agl and at 10 to 15 knots indicated airspeed, he lowered the collective to initiate the landing. Immediately after lowering the collective, the engine lost all power. The pilot entered a hovering autorotation and applied collective pitch to cushion the landing. The helicopter struck the ground hard and a post crash fire ensued. The occupants egressed the helicopter unassisted.

                    A witness stated that he was at the airfield outside of his hangar. He noticed the helicopter depart the airport. About two hours later, he heard the helicopter approaching the airport and watched it until it was about 60 ft agl approaching to land. The witness walked inside his hangar and from inside, he heard three or four pops in rapid succession followed by a louder, deeper sound. He then heard the helicopter hit the ground with a loud impact. He went to the door to observe the helicopter on fire. He then ran to the helicopter to render aid to the two occupants exiting the helicopter.

                    The helicopter came to rest on the airport, about one quarter mile northwest of the approach end of runway 34, at an elevation of about 4700 ft above mean sea level (msl). All major components were located in an area of about 50 x 50 square feet. A postimpact fire consumed the fuselage and the tail boom. The engine, transmission, main rotor blades and the fenestron anti-torque system were recovered to a secure facility for further examination.
                    https://www.reddit.com/r/NTSB_databa...42j_minden_nv/




                    Given that Zis was enquiring about the Boscombe Down Gazelles ..


                    SA341C XZ939/G-CLGO (WA1750) as seen at Garford Airfield in Oxfordshire on 31st August 2020 (Photo by Ian Grove)




                    Another take on the newly painted G-ZZEL:


                    SA341B G-ZZEL (WA1152) as seen at Pembrey Airfield in Wales on 30th August 2020 (Photo by Paul Stevenson)




                    SA341G RA-07822 (cn.1073) as seen at Oreshkovo Airfield in Kaluga, Russia on 6th September 2020 (Photo by Valeria)




                    Check out the latest Gazelle for sale on the GazMart

                    Comment




                    • SA341B G-KEMH (WA1284) as seen at Redhill on 8th September 2020 (Photo by Pete Robinson)

                      Owned by Tabby Manning from Warlingham in Surrey.

                      Below: G-KEMH departing Redhill on 8th September 2020



                      SA342J YU-HES (cn.1057) as seen at Shoreham on 6th September 2020

                      Comment




                      • SA341F2 ZU-RNV (cn.1608) as seen at Camp Discovery in Limpopo, South Africa on 9th September 2020
                        (Photo courtesy of Jean-Pierre)



                        YU-HEV


                        SA342J YU-HEV (cn.1393) as seen at Usce-Kalemegdan in Serbia on 7th September 2020 (Photo by Misko Ruvidic)








                        SA342M F-MGAF (cn.3664) as seen at Poitiersโ€“Biard Airport in France in July 2020 (Photo courtesy of 5RHC)

                        In July F-MGAF suffered some sort of technical malfunction which necessitated that she be roaded. The recovery was performed by l'escadrille de maintenance d'hรฉlicoptรจres nยฐ4 (EMH4).




                        D-HEMS car park landing

                        Comment


                        • xbdt
                          xbdt commented
                          Editing a comment
                          It normally does not need 10 people to put a helo on a trailer. I don't like the way they ship a complete helicopter on the road. Not sure if this stand was designed to transport a helicopter; the only reason I could think of if there was a landing gear failure.

                        • Savoia
                          Savoia commented
                          Editing a comment
                          '๐™„๐™ฉ ๐™ฃ๐™ค๐™ง๐™ข๐™–๐™ก๐™ก๐™ฎ ๐™™๐™ค๐™š๐™จ ๐™ฃ๐™ค๐™ฉ ๐™ฃ๐™š๐™š๐™™ 10 ๐™ฅ๐™š๐™ค๐™ฅ๐™ก๐™š ๐™ฉ๐™ค ๐™ฅ๐™ช๐™ฉ ๐™– ๐™๐™š๐™ก๐™ค ๐™ค๐™ฃ ๐™– ๐™ฉ๐™ง๐™–๐™ž๐™ก๐™š๐™ง.' โ€” This is the Army XB. Why use three people when you can use ten! ๐Ÿ˜„ In reality they probably used this as a training exercise for members of EMH4.

                          '๐™‰๐™ค๐™ฉ ๐™จ๐™ช๐™ง๐™š ๐™ž๐™› ๐™ฉ๐™๐™ž๐™จ ๐™จ๐™ฉ๐™–๐™ฃ๐™™ ๐™ฌ๐™–๐™จ ๐™™๐™š๐™จ๐™ž๐™œ๐™ฃ๐™š๐™™ ๐™ฉ๐™ค ๐™ฉ๐™ง๐™–๐™ฃ๐™จ๐™ฅ๐™ค๐™ง๐™ฉ ๐™– ๐™๐™š๐™ก๐™ž๐™˜๐™ค๐™ฅ๐™ฉ๐™š๐™ง ..' โ€” It looks like part of a maintenance jig.

                          '๐™„ ๐™™๐™ค๐™ฃ'๐™ฉ ๐™ก๐™ž๐™ ๐™š ๐™ฉ๐™๐™š ๐™ฌ๐™–๐™ฎ ๐™ฉ๐™๐™š๐™ฎ ๐™จ๐™๐™ž๐™ฅ ๐™– ๐™˜๐™ค๐™ข๐™ฅ๐™ก๐™š๐™ฉ๐™š ๐™๐™š๐™ก๐™ž๐™˜๐™ค๐™ฅ๐™ฉ๐™š๐™ง ๐™ค๐™ฃ ๐™ฉ๐™๐™š ๐™ง๐™ค๐™–๐™™.' โ€” This is a subject not often discussed, but there are real concerns when it comes to roading aircraft. Avionics and dynamic components can truly suffer should the trailer encounter a sufficiently serious bump in the road.
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