Roban - World Class Scale Helicopters

Official Freewing Twin 70mm SR-71 Blackbird with Gyro EDF Jet Thread

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  • DCORSAIR
    My R/C addiction started in 1984

    • Jan 2017
    • 1918
    • Selma, Ca.
    • Send PM

    #281
    Originally posted by Aros

    Alright, you, fine sir get the GOLD Star!! I don’t know for sure if it’s the fold half and then half again thing but I followed your instructions to a tee, powered her up, hit the switch…

    It flew out of that compartment like it was running from a crime scene!

    Thanks bud! I feel a video is worth creating to show others who are having issues with chute deployment a sure-fire method that works!
    Well hopefully it works for you more than once...

    Not bragging but I would have had 28 out of 28 times that it worked but I left the chute packed all week one time and it did not like that at all, on the next flight it flew out of the door and did not do anything but tumble behind the bird and would not open, so after that I just stuffed it loosely in one of the exhaust nozzles for storage and it worked every time after that so good luck......

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    • Aros
      Lead Adminstrator / Warbirdaholic

      • May 2013
      • 8207
      • Astoria, OR
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      #282
      Im gonna brag about your technique in RCG so deal with it.

      My YouTube RC videos:
      https://www.youtube.com/@toddbreda

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      • Nino
        Member

        • Jul 2017
        • 10
        • Send PM

        #283

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        • Nino
          Member

          • Jul 2017
          • 10
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          #284
          I bought one and wanted to discuss grass ops and/or mods to allow it. I have a very manicured short grass runway at my field, and I noticed a review from James H. stating that it takes off very well, around 200 feet. Does anyone else have any input? Thanks

          Nino

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          • GliderGuy
            Senior Member

            • Oct 2018
            • 1408
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            #285
            Originally posted by Nino
            I bought one and wanted to discuss grass ops and/or mods to allow it. I have a very manicured short grass runway at my field, and I noticed a review from James H. stating that it takes off very well, around 200 feet. Does anyone else have any input? Thanks

            Nino
            Watch his attempts to use grass.

            They Warned Me About This Jet.. Freewing SR-71 Maiden - YouTube

            Looks “IFFY” at best.

            -GG

            Comment

            • Aros
              Lead Adminstrator / Warbirdaholic

              • May 2013
              • 8207
              • Astoria, OR
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              #286
              There’s a reason we insist this bird is not meant for grass. Unless your field’s grass is as short as a golf course, it’s definitely not recommended.
              My YouTube RC videos:
              https://www.youtube.com/@toddbreda

              Comment

              • EDF-Jetpilot
                Jets are a lot of fun
                • May 2024
                • 129
                • Aarburg, Schweiz
                • Send PM

                #287
                Originally posted by Nino
                I bought one and wanted to discuss grass ops and/or mods to allow it. I have a very manicured short grass runway at my field, and I noticed a review from James H. stating that it takes off very well, around 200 feet. Does anyone else have any input? Thanks

                Nino
                I think everyone should finally realize that this beautiful machine simply isn't made for grass. Anyone who dares to do so will sooner or later end up ruining the machine. There are much better things to do than punishing an SR-71 with grass, right?

                Comment

                • Aros
                  Lead Adminstrator / Warbirdaholic

                  • May 2013
                  • 8207
                  • Astoria, OR
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                  #288
                  I get why people ask, because the majority of us do fly off of grass fields. Sadly, some models - like this one - are not made for grass, period. It's not impossible, but again, the grass better be like a putting green or you are asking for problems.
                  My YouTube RC videos:
                  https://www.youtube.com/@toddbreda

                  Comment

                  • GliderGuy
                    Senior Member

                    • Oct 2018
                    • 1408
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                    #289
                    Made 10 late afternoon SR-71 flights today. This puts me about 75 or 80 flights. Here are some general observations based on being more familiar with the bird.
                    - She flies very similar to most EDF jets this size.
                    - No bad habits…loops, rolls, inverted are all good. I have avoided stalling her.
                    - Seems to feel better with a little touch of added throttle when the gear are put down.
                    - 3:30 at 60% cruise leaves plenty in the tank for a go-around even after a couple of high speed passes with a 6000 mAh battery.
                    - With factory CG, she’s a ground lover on take-off. But apply lots of up elevator and as soon as the nose rotates, quickly ease off the “up” and “wheelie” her on the mains to liftoff. Looks sooo cool.
                    - If a tad slow on final down low, she responds well to a burst of power if she begins to drop. A few times, I have stopped the drop with up elevator. She will stop the drop, but this will drag the bottom of the jet nozzles. That makes one heck of a noise.
                    - I am comfortable with the sight picture as she flies around. Not that hard to tell what she’s doing, “IF” you pay attention.
                    - After beefing up the anti-torsion bars on the landing gear, I have had no more issues.
                    - You really CAN make good landings with her at the factory CG.
                    - I am not uncovering any airframe structural design issues. I’m not seeing any stress creases in the foam anywhere.

                    So bottom line…nothing unusual about the SR-71 if you are an experienced large EDF jet pilot. She’s a solid flier. One day I may tweak the gyro sensitivity up on the ailerons to reduce the wing rock on final that sometimes happens. For now, I just ignore the slight wing rocking and don’t try to fight it when/if it happens.

                    -GG

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                    • GliderGuy
                      Senior Member

                      • Oct 2018
                      • 1408
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                      #290
                      A report about bad foam gatoring has reached me. So, be cognizant that care must be taken to not expose the SR-71 to mid-day sunlight.

                      To maintain the factory new finish this time of year, I’m going to fly early mornings and late afternoons only, unless it is overcast.

                      A cloth covering while in the transport vehicle isn’t a bad idea.

                      -GG

                      Comment

                      • Aros
                        Lead Adminstrator / Warbirdaholic

                        • May 2013
                        • 8207
                        • Astoria, OR
                        • Send PM

                        #291
                        Yep there's a reason we added a section on the product page about gatoring. Extreme caution is needed to avoid the dreaded basketball texture.

                        Click image for larger version

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                        My YouTube RC videos:
                        https://www.youtube.com/@toddbreda

                        Comment

                        • ggillila
                          Member
                          • Feb 2023
                          • 14
                          • Send PM

                          #292
                          I am the guy who reported it to GG, so i figured I should say my exact conditions so the rest of you can avoid it.

                          It was mostly cloudy, and the sun was behind a cloud for 2/3 of the time mine was outside. The plane was only outside for about 5 minutes including the flight. It was 75°

                          When I landed, I went to grab it and the entire right side looked like a snake, the side that faced the sun for maybe a minute when I was doing final checks. This was only my second flight :(

                          So this time of year, as GG said, unless it’s COMPLETELY cloudy, do not bother unless it’s early morning or late afternoon. I was very careful with mine because I’ve had something dark like this before, but can’t be too careful as read here.

                          As for the future of mine….its totally just aesthetic so obviously it’s not out of service and ready to fly whenever, no internal issues or anything. Nothing was hot internally (aside from the battery of course). As mentioned it’s only on one side…..a whole new meaning for “get my good side.”
                          Now I’m back and forth over if I should sand it down to give it the “wear” look with super fine sand paper because it’d give me a reason to get rid of the snake skin, or if i just leave it because you can’t see 5 feet away anyway (or on the good side)

                          Aros thoughts?

                          Comment

                          • ggillila
                            Member
                            • Feb 2023
                            • 14
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                            #293
                            Oh i just wanted to add
                            At the end of the day, enjoy it. Nothing is perfect. So while I am saying be more careful, I’m also saying enjoy it and don’t just have it collecting dust because you’re focused on keeping it perfect. Get a good balance🤙🏻

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                            • Evan D
                              I'll fly anything

                              • Jan 2016
                              • 5388
                              • Charlotte
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                              #294
                              I’ve had good luck rubbing a cold spoon across to reduce it.

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                              • ggillila
                                Member
                                • Feb 2023
                                • 14
                                • Send PM

                                #295
                                Originally posted by Evan D
                                I’ve had good luck rubbing a cold spoon across to reduce it.
                                I have been trying, i must be doing something wrong. I have the spoon in the freezer for about an 30 minutes, then rub aggressively, but I’m not having a ton of luck

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                                • Alphonso
                                  Member

                                  • Aug 2020
                                  • 101
                                  • Hastings, UK
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                                  #296
                                  Sanding alone will simply damage the surface of the individual foam cells and leave you with a fluffy surface. Fine grit is worse on epo, it removes nothing until it it goes too far. I have sanded EPO successfully with course grit as it cuts and removes material. You then need to fill the damage done with a spackle and sand smooth but you have half a huge model to do and the panel lines make it an unenviable task. I would rather buy a new one than do all that for it to still look less than perfect.
                                  If you really want to do it, I would fill every panel line and do a full repaint. Would likely be quicker than trying to match the factory finish.

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                                  • Evan D
                                    I'll fly anything

                                    • Jan 2016
                                    • 5388
                                    • Charlotte
                                    • Send PM

                                    #297
                                    For me a gentle but firm push, you are compressing each cell back flat.


                                    Originally posted by ggillila

                                    I have been trying, i must be doing something wrong. I have the spoon in the freezer for about an 30 minutes, then rub aggressively, but I’m not having a ton of luck

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                                    • GliderGuy
                                      Senior Member

                                      • Oct 2018
                                      • 1408
                                      • Send PM

                                      #298
                                      OoooEEEE!!!!! I am here to report more EXCITEMENT than a flea has when seeing an elephant!

                                      YOU CAN survive an elevon servo failure!

                                      Took off and she didn’t feel quite right after about 15 seconds. Made a left cross wind turn at about 200 ft up and she went into a steepening left bank with the nose dropping. Not responding!!!!

                                      A fleeting vision of a pile of foam snapped my years of experience into action..RUDDER!!!! SWITCH ROLL CONTROL TO RUDDER!!! Maybe it will work?!

                                      Sure enough, with a few seconds to impact, she rolled level and pitch became sorta active. I got her level and made a hasty yet gentle pattern to land. On final, she was rapidly oscillating in roll 45 degrees bank right to 45 degrees bank left.

                                      Luckily, she touched with 0 degrees bank…lucky timing.

                                      So why did she go bonkers when the outer right elevon servo fail? That was the failed control. My guess is that the gyro was having a tough time figuring out what inputs to feed the servos with one failed. I surmise this from the rapid bank oscillation on final approach.

                                      Now….where’s that spare servo?

                                      -GG

                                      PS My RC Experience gained since 1965 paid off handsomely this evening.

                                      Comment

                                      • f4u ausie
                                        Senior Member

                                        • Dec 2019
                                        • 1232
                                        • Melbourne
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                                        #299
                                        Good job gg. U cannot. Ever. Ever. Beat experience no matter what

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                                        • GliderGuy
                                          Senior Member

                                          • Oct 2018
                                          • 1408
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                                          #300
                                          Reference my post 302 above….

                                          If you elect to upgrade from the 4 stock 17g wing control servos, the MKS HV69 is almost a perfect fit replacement. Some very minor Dremel adjustments to the white plastic wing servo sockets and the servos’ mounting tabs is all that is needed.

                                          I used these in the past and on the MiG-29 full flying stabs with good results.

                                          Note: They talk to you a lot more while sitting idle on the ground…especially if a gust blows on the control surface. They fight the gust’s attempt to move the control surface with an auditable sound.

                                          -GG

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