Official Roban 120mm A-10 Warthog V2 EDF Jet Thread

[horsefeetky]

wow a month gone by and no flight report yet...

[jinkrat4791]

I was totally wrong about the A-4's AOA sitting on it's gear, I don't why that big carf model has an actuator on the gear to raise the nose, it's probably a feature on the full size as well because I did see a couple picks of A-4's sitting slightly nose down.

[jinkrat4791]

Ground stance (including nose AoA) is a concert with thrust line and other factors, but suffice to say I think increasing the nose AoA is more likely to help than hurt this model's rotation characteristics.

thanks alpha, I think it will help alot, have you ever seen the CARF A-4 Skyhawk take off. It actually has an actuator on the nose wheel that raises the angle of attack considerably. The model and the real aircraft have a pretty extreme nose down attitude sitting on it's gear, the real bird takes a loooong take off roll to rotate. The model was the same if not worse that is why Mitch at D&L came up with the whole nose wheel actuator deal, and if you look at all the A-10 foamies, they all have a slightly positive angle of attack sitting on their gear. The roban A 10 has a slightly nose down AOA which I believe is scale, but I'm trying to build a model that flies and handles as good as it's going to look. And those mains are waaay behind the CG. All opinions from anyone is appreciated

Adding a little edit here, I believe the A-4 was primarily used launched off Aircraft Carriers. It's not like anyone has a mini 100 ft aircraft carrier to launch their 1/4 scale A-4 Skyhawk off of to start with, I'm pretty sure the whole nose actuator thing is to maintain scale look and taxi, but if you google the vid of the CARF model taking off you can see how much they raise the nose after getting lined up for take off. And if you remember back to the old Byron A-4 the gear was no where near scale. It had a really high AOA. I know that there are other factors involved in the rotation performance but changing the AOA on this A-10 is the only way I can come up with to try to improve takeoff performance. If there's something anyone else can suggest I'm all ears

[Alpha]

Ground stance (including nose AoA) is a concert with thrust line and other factors, but suffice to say I think increasing the nose AoA is more likely to help than hurt this model's rotation characteristics.

[jinkrat4791]

Listen guys , I have an idea. Everybody that's flown this bird says it's really hard to rotate on takeoff because the mains are so far behind the CG. I'm thinking of getting Mitch at Down and locked to make me a longer nose strut, there's room, just haven't measured how much I can get away with yet. And slightly shortening the mains so it's not terribly noticable that they are a little further back in the pods than normal. It would give it a better angle of attack on takeoff and should help with the rotation problem. Any thoughts

Jink

[jinkrat4791]

Shop envy? I lost my humble little workshop in the split when we sold the house. This is the first giant scale plane I've built on a kitchen table. Had it not been an arf for the most part, I'd have never attempted it, still no word on the maiden? wish you the best of luck

Jink

[Pogo]

It inspires me to go spend 200k on my shop...oh wait, I don't have 200k. It is beautiful.
Best of luck with the A-10.
Tom

[T-CAT]

Wow! That shop really is phenomenal.

[Aros]

Definitely Shop Envy. My shop is basically a tiny workbench shoved in the corner of my garage. Sigh.

[OV10]

Is it just me, or does anyone else on this forum have a severe case of 'shop jealousy' from those photos? Ha ha.

Nope it is not just you...……..I was gonna make a comment yesterday of what a nice workbench in pic 4 but then somehow got side tracked and didn't

[gravity tester]

Is it just me, or does anyone else on this forum have a severe case of 'shop jealousy' from those photos? Ha ha.

[gravity tester]

Looks fantastic. That lighted panel is cool! Hope the maiden is flawless.

[Aros]

Nice! Look forward to maiden video/report! Good luck!

[jinkrat4791]

Looks great, when do you plan on doing the maiden?

[bdipenta@gmail.com]

Just finished the build

[jinkrat4791]

Have you considered putty and paint so you can later take it apart if necessary, or another less permanent approach? Just thinking on that and wondering, so would like to hear your thoughts.

The bottom of the nacelle pod is solid, I'm cutting enough of that material away for easier access, I want the permanent mount for strength

[jinkrat4791]

Wow, I had to take some time away from the build and thread, so a lot has been posted. Thanks to all.

Jinkrat, the Down and Locked upgrade, did that include electric brakes as well? For my field, I believe I really need them to ensure stopping with the approach we have. Agree on wanting the strength.

No brakes included, he does have his break system in production now I believe, he didn't at the time of my upgrade

[PeterGRC]

I'm strongly considering hysoling the nacelles to the fuselage. The reason being is I am really leaning towards getting rid of those giant screw access holes in the top of the the thing and filling and blending where it's mates up to the fuse. To me it's got a giant foamie look to it, just screwed together. It wouldn't be difficult and it won't add enough weight to be of any concern. It won't kill me on time either.

Do y'all think it will improve the looks enough to be worth it. And remember I like doing this kinda thing do it's not a chore or anything? And with my snow cammo scheme going on most of the work will be covered, the little that isn't can be easily blended back in. I already had the matching paint and my two Grey's for the job mixed and ready to go

Have you considered putty and paint so you can later take it apart if necessary, or another less permanent approach? Just thinking on that and wondering, so would like to hear your thoughts.

[PeterGRC]

Sisaksen, my gear was rebuilt with bigger, stronger motors and a nice controller with door sequencers by Mitch at Down & Locked. He also machines all new parts for it including the trunnion. Only thing original is the frames. It cost $650 with the sequencer &500 without. Worth every penny. These are top quality retracts now and bullit proof too in my opinion. This much money in a plane, I want the wheels to come down every time I flip the switch. They are running on a standard 2s life battery at 6.6v. If you watch some of the YouTube vids of these things flying, in several of the vids they are flying around with the gear only partially retracted because the motors on the factory gear are not strong enough to raise the gear with the added wind resistance during flight. I saw you ask about an Electron replacement in the other thread. It's not much cheaper than the upgrade and it's quite a bit of work to fit them. With the upgrade they just bolt right back in

Wow, I had to take some time away from the build and thread, so a lot has been posted. Thanks to all.

Jinkrat, the Down and Locked upgrade, did that include electric brakes as well? For my field, I believe I really need them to ensure stopping with the approach we have. Agree on wanting the strength.

[jinkrat4791]

Hi Jink-
I am so far from an expert I can't even see the "E" but I offer this for what it is worth since they are similar airframes. Like you, I am running 2 LiFe batts for my Rx in the CGRC (Spektrum 2310 Powersafe 12 ch.) but also running a separate 7.4V batt for the landing gear which are older model Century Jet (R.I.P.). Not sure what D&L requires for power? I found I needed the extra nose weight anyway so it is not a burden. Bottom line is I have 7 batteries total to get the pig airborne.

I charge those LiFe at 1c as I do all of my LiPo's for my other planes, unless I am really in a hurry. Then I charge at 1.1. Ha ha. IMHO, there is just no need to force feed the battery any harder. The time savings of a few minutes of my day charging at 2.0 C for example, is not worth the overall risk. With a couple packs in rotation, by the time I am ready to fly again, so are the batteries if that makes sense. I store the LiFe's at or at least "government work close enough" to the 3.3V that OV10 showed above.

As far as charging, my main charger now is a 1000W PowerLab 6 Touch. This thing can tie my shoes and make me coffee and it probably has features I don't even know about yet but I like the battery parameter history and the different geeky charge details it records, even if I don't know what they mean. It also has a Bluetooth connection to an app on my phone that says "...Hey idiot, your batteries are done..." I use it with a parallel board and can charge 4 batts at once but normally only charge 2 at a time so I don't tax the solar system at our field. 2 6S 5000's at a normal "fill up" takes 30 minutes or less - about the time the pizza arrives. I don't use the RFID "bump tags" the charger comes with. Honestly, they are really cool but the total time savings is about 7 seconds since the batteries are stored in the charger memory. A couple button presses and you are off.

Hope that helps. PS. My A-10 obsession probably requires professional help. I forced (sic) myself to buy a T-33 and also have a F-100 "Hun" on order so I could make myself feel normal.

Cheers.

I pretty much know what I needed to know now, I've only charged and used one of my life batteries playing around with my retracts. The voltage was a little low so I charged it up to the proper storage voltage last night. Hopefully I didn't damage it. The power safe receivers were un available for so long I ended up going with the spektrum 9 channel. I'm using one 2s 2200 to run the receiver and the other to power the retracts and lights. I really wanted the power safe receiver for piece of mind but you couldn't get one. Had one on backorder but they kept pushing the date back.