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Official Freewing JAS 39 Gripen 80mm EDF Jet

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  • Originally posted by TangoVector View Post
    "It's better to burn out than fade away"
    That's the spirit!

    Originally posted by DannyR1 View Post
    Hey guys did any one have problems with there Gripen retracts...?
    No problems with retracts but the struts bend rather easily and then the gear doors will not close. Also the gear door hinge pins are way too thin and they break.

    Hope they would beef them up in future batches. Drilling four holes at the same cross section is not a fantastic idea, and making slightly beefier (bigger diameter) gear door hinge pins should be a no-brainer.

    Comment


    • AIRGUARDIAN - first off, I want to say thanks for all the inspiring videos and sharing your knowledge on the jet.

      My maiden flight was so "uneventful" that the most controversial thing we talked about was that my camera-man forgot to hit the button to start recording! LOL! Takeoff roll had a little curve to it because I forgot to roll the plane on the ground...it looked "right" when I eyeballed it and that was the one thing I forgot to do. I manually compensated, and nobody knew it was out of trim but me. Pulled back on the stick, as soon as the nose broke ground, I relaxed the elevator back to neutral and "nothing"....she didn't change her attitude and just kept gently climbing at about 25% angle. Gear up. Then I cautiously pulled on the elevator...actually felt too mushy at 50% expo....but smooth. (No gyro). Now time to turn...same neutral feel...just stayed put. Saw a little wiggle so I'll try trimming a few degrees down, but really nothing to speak of here. One click "down", one click "left", throttled back to probably 60% power downwind and felt like I've been flying this jet all my life! I would say it is as smooth as my Avanti...or maybe close.

      Today IS a lucky day! My first flight, I came in pretty quickly because my new radio wasn't counting down, and my gut told me to not push it on the maiden flight. Take off, trim, land. I flew about 2.5 minutes and landed...with 23% left on my HRB 6000! I expected it to be around 50%. Cell going bad? They're about 1 year old, and I never overheat them. I have 3.. so I flew again, with a short timer 2.5 minutes....second flight is below. I kept it very short to make sure I wasn't just burning batteries, but this time I landed after 2. 5 minutes with 53% left - more like I expected.



      I really have forgotten just how "nice" JR radios are, this 11X feels really solid and luxurious compared to Spektrum. More like my higher-end Graupner. Miss you, JR! I like my new RadioMaster TX16s, too, but it just doesn't feel like the JR.

      OK....so for tonight...fix the tracking on the front wheel, add in a couple of MM of down canard.
      Next flights on Thursday! Can't wait! Hopefully I'll get my afterburner installed before then (waiting on a package from Gooniac!)

      (I woke up like 5 times last night, anxious to get the first flights out of the way. LOL, I had no need to be nervous. The F16 feels much more loose and squirrely in my opinion, too. Really like...no, love this Gripen!

      Have a great week everyone!


      Originally posted by Airguardian View Post
      Good news for Gripen owners!

      I decided to do some testing with stock power before proceeding to install the 80mm Jetfan.
      Checked out the ESC with programming card and it comes stock at medium timing... so I set it up to high timing instead (and set low voltage cut off at minimum while at that) and tested the jet out in the field. What a difference! It's still not the most 'lively' setup but the increase in thrust was considerable, and the amps didn't skyrocket too badly. I was still able to make 4:00 - 4:30 min flights with plenty of sustained full-throttle (throttle management too, of course) and batts came down at 3.7v/cell. Hotter and more puffy than usual but they are Nanotechs, it is to be expected. Panthers wouldn't have a problem with this and other newer, better batteries won't either. I can not tell you that this will not over-stress the ESC and/or motor over time and eventually kill them (as I only made two flights so far) but they seemed to take it well enough.

      So, for those wondering, they can squish more juice out of their stock setup with this little trick. Quite worth it if you ask me, the jet was more enjoyable.

      Comment


      • Thank AIRGUARDIAN. I just set my timing to high. I’ll give it the shot next weekend.
        however today I flew her and decided to move the battery more forward. It just Sean to heavy at 130 and was a PIA to land. So after moving the CG more towards the 122 mark she flew fantastic. I was even able to use my 5200 pack shoved as far back as it could go. Had to great (but underpowered) flights. S after I was done I marked my new spot.
        After I got home decided to actually put a ruler on it and find out where I was. Well you guess my original highly calibrated assumption needs to be recalibrated. My new CG measured at 132. That means my old CG must have actually been like 140-145. No wonder she flew so slippery.
        time to get my guesstimater zeroed and recalibrated. I hope the timing makes as big a difference as you seen. Otherwise I’ll still be looking for a upgrade.

        Gravy

        Comment


        • Originally posted by Airguardian View Post

          No problems with retracts but the struts bend rather easily and then the gear doors will not close. Also the gear door hinge pins are way too thin and they break.

          Hope they would beef them up in future batches. Drilling four holes at the same cross section is not a fantastic idea, and making slightly beefier (bigger diameter) gear door hinge pins should be a no-brainer.
          I did break a main gear door hinge pin already. Admittedly, I've brought some landings in at too high an high alpha and scraped the tail skid which is tough on the gear. I've also had the front hinge pin pop out in flight (without breaking) when extending the gear. The gear door will stay attached by the ball links and it creates pitch abnormalities which worsen at speed if that happens.

          It also helps to loctite the main gear grub screws as when they come loose, the gear doors won't close fully.

          Comment


          • Hi Aprillamgt
            Think that the Gripen is not due in untill early January in the European warehouse

            Comment


            • Guys, how do you set the timing on the ESC? What is the stick-sequence to make this happen?

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              • Originally posted by Captain Moron View Post
                Hi Aprillamgt
                Think that the Gripen is not due in untill early January in the European warehouse
                Well that's a shame ,. I had about £300 in vouchers to use , would of been a great Xmas present to myself

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                • I might be wrong but that is what I was told.

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                  • Originally posted by Marktur View Post
                    Guys, how do you set the timing on the ESC? What is the stick-sequence to make this happen?
                    Download the ESC manual from the product support page.

                    Comment


                    • Can't you preorder it? Even if the web site doesn't let you maybe make a phone call and do it?

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                      • Cheers, might wait for a official response from motion ?? James or alpha ?

                        Comment


                        • Here's something you don't see every day!






                          Originally posted by Marktur View Post
                          AIRGUARDIAN - first off, I want to say thanks for all the inspiring videos and sharing your knowledge on the jet.

                          My maiden flight was so "uneventful" that the most controversial thing we talked about was that my camera-man forgot to hit the button to start recording! LOL!
                          Thanks! I certainly try to keep the bar 'high' for entertainment! ​​
                          And congrats on your maiden! :D

                          Originally posted by Gravythe clown View Post
                          Thank AIRGUARDIAN. I just set my timing to high. I’ll give it the shot next weekend.
                          Done a few more flights with it and not a single problem so far! ;)

                          Originally posted by Marktur View Post
                          Guys, how do you set the timing on the ESC? What is the stick-sequence to make this happen?
                          I used the Hobbywing programming card.

                          Comment


                          • Good luck with that. I kept asking about the TVs when it didn’t come when they said and was told by James I sounded angry and to message him if I wanted answers.

                            I messaged him for an update and also posted asking for an update almost two weeks ago and never got replies.

                            And then there’s the silence about the Big MiG...

                            Comment


                            • In positive news, I flew my Gripen for the first time with the FMS edf unit. With the battery (5000mAh) at the very rear of the compartment it flew pretty damn great.
                              The roll axis feels a little unstable with a tendency to rock, but it seems like that's a feature of deltas.
                              I decided to fly it more scale, and disabled the canards as default, but could turn them on with a switch of course. The plane flew perfectly fine without the canards, much better than I expected. Pitch and roll were plenty quick, but of course there was a ton more authority with the canards on. In general I liked flying without the canards enabled.
                              Tracks straight and true, CG is about a fingers width behind the molded mark. Flight times are just 3:00 with a 5000mah, but that's with a still-not-comfortable-with-the-stall-speed high average throttle application.

                              Comment


                              • Congrats! Awesome!

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                                • Originally posted by KevinMar View Post
                                  The roll axis feels a little unstable with a tendency to rock, but it seems like that's a feature of deltas.
                                  And not just deltas. Did you fly in calm weather? Most of the wing rocking is caused by air turbulence. Nose heaviness doesn't help.
                                  A gyro can smooth it out and you may find that having canards slightly trimmed pitched down can help a bit with that (and hooking canards on a gyro while having them work in pitch only will help too).

                                  Try to fly the jet on a zero-wind day and see if the wing-rocking persists.

                                  Comment


                                  • Originally posted by Airguardian View Post

                                    A gyro can smooth it out and you may find that having canards slightly trimmed pitched down can help a bit with that (and hooking canards on a gyro while having them work in pitch only will help too).
                                    I was flying with a bit of a crosswind, and with neutral canards.
                                    While I was taxiing for my second flight of the day, for which I had the canards pitched down a bit to condition the airflow over the main wing, the winds shifted and the airfield was closed down due to the local airport flipping its takeoff/landing directions to conflict with our airspace 😔

                                    Next flight will have the canards at an attitude to aid in the flow over the wing, like the real thing 😃

                                    Comment


                                    • Originally posted by KevinMar View Post
                                      In positive news, I flew my Gripen for the first time with the FMS edf unit. With the battery (5000mAh) at the very rear of the compartment it flew pretty damn great.
                                      Congrats on the maiden!
                                      What motor are you using with the FMS edf? I'm going to at the very least swap the fans. I saw a real difference when I did it on my 70mm Freewing F-16. Longer flights, equal or better power.

                                      Comment


                                      • Marktur This was my second flight, but first with the FMS EDF with the 3280 2100kv motor, so I had a good back to back comparison between stock and this setup.

                                        Comment


                                        • Originally posted by KevinMar View Post
                                          Let me attempt to steer this back on course.

                                          Still trying to solder my FMS 80mm unit. The enamel coating on the stranded wires is a headache, and I have not found the correct solution to dissolve the coating so I can solder some extensions on it.
                                          Other than mechanical means of removal such as sand paper and scraping, anybody know how to remove this damn coating?
                                          Well, that's why you are not supposed to cut those wires and use the pre-tinned part of the motor wires. It's almost impossible to solder that stuff.

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