Official Freewing 80mm A-4E/F Skyhawk Thread

[Bushong572]

The finish on this plane is one of the best I've seen from Freewing.............the quality control was not so good.

[seaviper]

Yeah Freewing QC is hit or miss. Sometimes you get a great one. Sometimes you get a junker. That's why I wish they would just sell them as kits for us builder types.

[e4dragongunner]

I think I am just going to go with a Hitec HS 85 BB for the elevator off the bat. Why screw around!

[skippykix]

Hey guys, I have an issue with my scooter and I'm looking for some suggestions. On flight #8 I went ripping down the runway and right after liftoff she went completely dead. She came down still on the runway, bounced and flipped upside down. Unbelievable there was no damage! I walked up to the plane and there was nothing, no receiver signal, no turbine, nothing. It's like the battery was disconnected. Took it back to the Pitts, unplugged the battery which was still pretty much fully charged and proceeded to plug the battery back in. When I did the ESC started beeping rapidly, it still would not do anything (servos or turbine) until I cycled the throttle and she came back to life! Ran her up in the Pitts for a minute or two and still everything seems fine. I suspect the ESC crapped out on me but I can't be 100% sure. Im pulling 103 amps on a fully charged battery for a few seconds before it drops below 100. For reference it's a stock scooter, Thunder Power Rampage 70c 5000 battery and Jeti for a radio system. I'm scared to death to try to take it back up as I feel I got really lucky on this one. I'm thinking of replacing the ESC with a slightly larger one, what do you guys think?

[OV10]

Hey guys, I have an issue with my scooter and I'm looking for some suggestions. On flight #8 I went ripping down the runway and right after liftoff she went completely dead. She came down still on the runway, bounced and flipped upside down. Unbelievable there was no damage! I walked up to the plane and there was nothing, no receiver signal, no turbine, nothing. It's like the battery was disconnected. Took it back to the Pitts, unplugged the battery which was still pretty much fully charged and proceeded to plug the battery back in. When I did the ESC started beeping rapidly, it still would not do anything (servos or turbine) until I cycled the throttle and she came back to life! Ran her up in the Pitts for a minute or two and still everything seems fine. I suspect the ESC crapped out on me but I can't be 100% sure. Im pulling 103 amps on a fully charged battery for a few seconds before it drops below 100. For reference it's a stock scooter, Thunder Power Rampage 70c 5000 battery and Jeti for a radio system. I'm scared to death to try to take it back up as I feel I got really lucky on this one. I'm thinking of replacing the ESC with a slightly larger one, what do you guys think?

Skippy.............Replacing the ESC is most likely the most prudent decision.
Trying to troubleshoot and or replicate electronic anomalies has always been a buggar of a deal for techs without the proper equipment to do so.
Keep the suspected 'bad' as a bench unit. Replacing with a slightly larger amp rated one isn't going to be of harm other than drain your pocket a little harder.
If your running the stock motor, there is really no need to upgrade. ;)

[skippykix]

Skippy.............Replacing the ESC is most likely the most prudent decision.
Trying to troubleshoot and or replicate electronic anomalies has always been a buggar of a deal for techs without the proper equipment to do so.
Keep the suspected 'bad' as a bench unit. Replacing with a slightly larger amp rated one isn't going to be of harm other than drain your pocket a little harder.
If your running the stock motor, there is really no need to upgrade. ;)

Thanks for the advice Charlie. I have another thought on what may have happened. Does anyone think if I sucked up some junk (I fly off a grass field) that it may have spiked the amps in the ESC thus shutting it completely down?

[RCjetdude]

Could be an overheated ESC? I had mine (different brand of ESC's) do that on my A-10 but I still had power to the radio though. Could you have a bad crimp/loose connection on the throttle lead from your ESC. That happened to my Stinger 90 but fortunately not while in the air. It really could have cause the loss of the aircraft though.

[The RC Geek]

Hey guys,

I haven't been very good at keeping up with the discussion on the squawk, but I finally got my A-4 refinish done over the weekend. The whole airplane was refinished by sanding lightly the stock paint, spraying a couple coats of polycrylic and then primering. I did at least 3 passes of the primer/sand/primer approach and the painted the whole airplane. For weathering, I used some different consistency washes and airbrush shading to get the overall finish I was looking for. I usually like to do a light airbrush fade in black over the panel lines, but I ended up not doing that on this on the top side because it darkened up the panel lines way too much. With this depth and size of panel lines, the goal was to subtly dirty them up, but not draw too much attention to them (you don't want the eye drawn straight to the panel lines). So, instead I airbrushed a lightened basecoat in the centers of the panels which gave it a nice faded look. The washes were done with acrylic Raw Umber. To highlight the panel lines, I thinned way down the acrylic raw umber and airbrushed it over the airframe and then wiped it all off with a paper towel and tamiya acrylic thinner. For streaking used the unthinned pigment wiping it off in a similar fashion. I'll post some pics of the process when I get a chance later.

I'm really happy with how the model came out and the finish came out really smooth. I've also been working on some 1/9 scale Mk82 bombs. I have them just about ready for the wing pylons (bombs in the pics were the first cut and a little small at 1/10 scale). The next step will be to draw and print the Multi-Ejector Rack (6pack) for the centerline. :)


Chris

[RCjetdude]

Chris, great job! Where did you get the nose strut?

[e4dragongunner]

Super COOL Chris. A vid on these processes would rock.
Also I see you modded the inside of the flaps to accommodate the decals. What did you use?

[e4dragongunner]

Ha..... seek and ye shall find! Here is your Vid!

https://www.youtube.com/watch?v=d-tocRK8CXc

[skippykix]

Could be an overheated ESC? I had mine (different brand of ESC's) do that on my A-10 but I still had power to the radio though. Could you have a bad crimp/loose connection on the throttle lead from your ESC. That happened to my Stinger 90 but fortunately not while in the air. It really could have cause the loss of the aircraft though.

When I pull the power system out if the plane I'll check it over.

[seaviper]

skippykix..what about the battery? What was it reading as far as cell voltage? Try running the power system on the bench and watching your battery cells.
The power coming back after cycling the throttle tells me that the battery could be suspect. Is it possible that you might have launched on a battery that was either damaged or not charged?

I now have 43 flights on the stock Scoot with no issues. It's pretty much my standard Sunday flier and battery tester machine.

[RCjetdude]

I had what I believe was a brown out at eWeek with mine. I was dropping the gear and turning right onto final when suddenly I realized it was not doing what I was telling it to do. It started a rather flat turn to the left while I was wiggling the sticks trying to get it to respond to something. I was just about to shout "A-4 no control" when I got control back and was able to immediately land it. I have not flown it since but decided to add a separate 8A BEC. I had a Lemon 10ch receiver in it but have since replaced it with the Admiral 10ch with diversity satellite as well. Prior to that I never had any trouble from it.

[skippykix]

skippykix..what about the battery? What was it reading as far as cell voltage? Try running the power system on the bench and watching your battery cells.
The power coming back after cycling the throttle tells me that the battery could be suspect. Is it possible that you might have launched on a battery that was either damaged or not charged?

I now have 43 flights on the stock Scoot with no issues. It's pretty much my standard Sunday flier and battery tester machine.

The battery was reading 4.13 to 4.15 per cell after the incident. I remember it died right after liftoff and when I hit the gear switch. So maybe full throttle (103 amps) and pulling the gear up was just a little too much for the ESC. When I put the battery on storage charge it pulled out approx 1200 mah so I know the battery had plenty of juice.

im going to attempt to replicate what happened on the bench today before I pull the plane apart. Fully charged battery, full throttle and pull the gear up and see what happens.

[The RC Geek]

Ha..... seek and ye shall find! Here is your Vid!

https://www.youtube.com/watch?v=d-tocRK8CXc

That vid covers most of it, but I did do a couple things differently here. The first of which was, since the panel lines are recessed (I opted not to fill them this time), was to spray a thinned down coat of the acrylic raw umber over the airframe to dirty up the recessed panel lines. I thinned it with water mostly and some tamiy acrylic thinner for it to flow a little bit. The other thing was I did not do the black airbrush shading on the top as it was darkening the panel lines too much (they're too big, so it was collecting in the recesses). So instead I faded the centers of the panels lightly with thinned down Gull Grey enamel that I added some white to.

Here are a few pictures of some of the process.


Chris

[The RC Geek]

Super COOL Chris. A vid on these processes would rock.
Also I see you modded the inside of the flaps to accommodate the decals. What did you use?

I realized I forgot to mention the flaps. All I did there was to line the inside of the flap with sheet styrene. Thickness was only .025" I think. I painted the plastic first, then traced out the pattern on the back, cut out the shape and then glued it on the flap with medium CA.


Chris

[e4dragongunner]

Seriously Chris, I can't thank you enough!

Excellent outline here sir!
You do Spectacular work! :Cool:;)

[themudduck]

I saw this picture on line today, thought it was pretty cool. Apparently this is an A4-K flown by Draken International as an "adversary aircraft" at Nellis AFB (Top Gun)

[The RC Geek]

Seriously Chris, I can't thank you enough!

Excellent outline here sir!
You do Spectacular work! :Cool:;)

Thank you! Let me know if you have any questions too.


Chris