Freewing 90mm EDF FA-18 Maiden Aborted!
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- čas přidán 21. 08. 2024
- RC Jim finally got the courage to attempt a maiden flight with his big ducted fan RC jet. Unfortunately it didn't make it into the air. Watch to see what happened, then comment below to share what you think the problem was!
Since then he has completed a successful maiden and subsequent flight. See: • Freewing 90mm EDF FA-1...
There is a small piece of wood about 2in. X 1/2in. That sits over the ESC, holding it in its little pocket of foam. It's both Screwed and glued in place I think.
I've had to rebuild my F-18 with new fuselage so that's how I came across that piece.
Most everyone with this plane has had some weird flight control problem or gear problem problem... sometimes intermittent. We resolved that by skipping the control box and plugging all the Flight controls directly into the receiver. I've keep the blue box for my lights and landing gear only. Other's just take it out all together. Very few people have kept the control box in there with stock connections.
It's a hard plane to get set up and dialed in. Some have terrible trimming on maiden.. I did. And almost universally... everyone agrees that this will maiden and fly much better with the CG at between 100mm to 110mm.
Mine flew very well at 105mm.
I've done wrecked mine twice. Both times pilot error. This last time I was in a hurry with a very short flight window and I forgot to take out the uncharged battery that I left in there for front end ballast for transport and to save battery power by using it to check out everything before flight. So I never switched out the battery and thus never positioned it for proper CG. It didn't go well!!! Never get in a hurry when going flying. I usually take more prep time than most people.... but not this time. Now i have to build my second one that I had as a backup in the box.
So be ready to trim hard once airborne. You may not have to. Some people don't have to. A lot do. While a CG of 105 is great, I had to put in about 34 units (clicks) of left trim to fly level. So just be ready for it. I think even the slightest disparity between the two elevators having no solid reference points to measure from or the slightest disparity between the flaps, even when fully retracted will cause unwanted roll.
Don't get to many complicated flight modes. You won't have enough time in the air as fast as this Flys to think about all those different settings.
I strongly suggest bypassing the blue control box for the flight controls after seeing your elevator issue.
if you choose to bypass the blue box.... simply discard the white ribbon cable. if you remove the little board that the ribbon strip connects to at each wing root, you will find that on the back side is just the basic servo connection for the aileron and the flap plugged into the back side of that small circuit board. just plug and route a servo extension lead from the servo cable at the wing route to the reciever. You may need an extension from the elevator Y connection to the receiver as well, depending on where you mount the receiver. That's all up to you.
Nose wheel steering would not work hooked up to the blue control box, but worked fine on a servo tester. So I had to run the steering servo to an open channel on my receiver as well.
There you have it. It's been a different experience for everyone it seems. Everyone seems to agree on the CG issue though.... 100mm-110mm. Good luck.
Hi Mark, Thanks for the detailed information. That's very helpful. Mine didn't have the piece of wood to hold the ESC in place. I did maiden the jet today. I waited until the dew evaporated off the grass. I used the factory setup with the box and all - mainly because I felt I needed to evaluate it that way for my CZcams watchers. It took a long takeoff runup, but with both of my flights it was able to get up OK without any big control issues. It needs a bit of aileron trim, but everything else was good. I didn't try to do anything fancy, just flew circuits. First landing was quite good, the second one I got it a bit squirrly, and it poked a wingtip into the turf. Just broke off the missle rack, but an easy fix. It certainly was a bit nerve wracking, but given that the battery doesn't last very long, at least that is limited!
I also only use the Blue Box for LG and lights. I also added an Assan AG-61 Gyro for the nosewheel. It disables the steering servo with wheels up without using a separate channel, but I put my NWS on a separate channel anyway. I'm using a Spektrum AR8360T. It allows me to trim the nosewheel separately and have full span flaps by putting ailerons on their own channel. Everything else plugs into the Rx. Since I fly off grass exclusively, I covered the cheater vent with wire screen after removing the plastic louvers. It keeps the ESC and EDF motor cleaner. It's a pain cutting the vent loose from the belly but it's worth it in the end. The front of the cover is held in place with a magnet. That allows me to get both hands inside easily when working on the EDF, ESC and EDF ducts. I also lined the inside and outside of the duct work with reinforced packing tape to hold the plastic piece of the main wheel wheels in place where it is part of the duct work. Those plastic pieces can come out and no one sells replacements. I have the servos setup for max torque, not max throws. I always use thick double-sided tape, NOT Velcro, to secure my Rxs or Stabs to the model. It's much more stable with tape.
i use the same receiver as well. I also use an unused trimmer switch assigned to the channel i have the steering servo plugged into in order to manually trim the steering. I set the mix on my rudder channel to operate the nose wheel steering and like you, i have it only activated when the gear switch is down. So, when gear is selected up, the nose wheel steering servo is essentially deactivated. Our set ups are about the same i think...except for the gyro you mentioned for the nose wheel steering. Can't seem to picture that or wrap my mind around that.
@@markhyde43 I'm using the control box that came with the plane for everything, so the stabilization for yaw is working both the nose wheel and the rudder when on the ground. I do like the idea of having the nose wheel on a separate channel, so that it can be set up with a separate trim. I've noticed when taxiing the jet down my driveway, that to trim the nose wheel to make it go straight, it ends up with a bit of offset in the rudders. Practically, it's not a big deal as I'm used to working the rudder on takeoff to keep it straight, but having the trim right certainly helps.
Further investigation following the video: The ESC was loose, likely dangling down in the air duct in front of the fan. Velcroed it in place and thrust increased to just over 3 kg. Still less than what we would have liked, but better than the 2.6 kg that we measured after the flight. Checked servo connections to the flight box, they were all in. Still guessing as to why the stabilators were going crazy, but they are in the back of the plane, and maybe some of the moisture found its way into their circuits. And certainly, for the motor, the ESC would have been dangling right in front of a blast of mist sucked up from the dew on the grass. Thrust would have been further decreased by grass clippings across the bottom intake. I'm going to try again later this week when things have dried out a bit.
The model should have come with a wooden bar with rubber on the side against the ESC. A screw on each end of the bar goes into a wood piece in the recess on each side of the ESC mounting cutout in the foam. If you remove the louvered cheater vent cover, and replace the louvers with screen, it will keep the ESC and EDF cleaner. The slats cut out easily with snips. I added 3 pieces of popsicle sticks across and under the screen to prevent sagging. I added a magnet to the front of the louver and recessed a magnet to the airframe at the front of that cheater vent so I could easily access the ESC/EDF duct work area. The plastic piece separating the main wheel wells and the EDF ducts can come off and get lost. I recommend adding reinforced packing tape to both sides but at least to the wheel well sides to keep it from coming off. No one sells replacements. If tape is added inside the duct, be sure the overlap is front to back and inspect regularly to make sure it isn't coming loose.
@@hifinsword I don't see your comment here about TextGen - it came through to my email. That wasn't available for Lemon RX at the time I did this video. Since then I've done a video to tell people about it: czcams.com/video/cbNM9GDuD9M/video.html
I recommend 3M double-sided tape instead of Velcro anytime you're attaching a stabilized Rx or a stabilizer to the airframe. It's more secure and eliminates vibrations to the stab. The only downside is it usually has to be replaced if you have to detach the Rx.
I did think about that very fact. What I am going to do is see if I can find the mounting point for the bar that is supposed to be there, and make really certain that it stays put!
A further thought about velcro on the RX. In this case, I have to pull out the RX in order to adjust the pots for stabilization. The velcro allows me to do that. Perhaps after I have finalized the settings, then I could replace the velcro with double sided tape. Alternately, perhaps attach it to a panel that slides in and out of guide rails.