Official Freewing 90mm F-4 Phantom II Thread

[jasmith41]

If you have EDF jet time, the F-4 is not much different. Next to the MiG-29, the F-4 is my favorite EDF. Nothing beats an F-4 for brute looks!

Some tips:
- Every one I have flown takes some right aileron trim right out of the box. See photo below. I have owned 3 F-4s….all needed this! Fail to start with this trim and you will be surprised by a hard left roll after lift-off….not fun.
- Buy some spare nose gear pins…they are brittle metal.
- CG and throws by the book are fine to start with.
- Elevator and flap mix BY THE BOOK.
- Flight times are relatively short…6000 mAh = about 3 min. throttle setting depending.
- Use pattern discipline….Here is what I do: 1/2 throttle on down wind then 4-5 clicks lower on base then adjust on final as needed to maintain glide slope. Typically this means 2-3 clicks lower on final. Ease the throttle to cut-off once in ground effect touching down slightly nose high. Careful not to hit nose gear first.
- If you rapidly cut power on final, the nose will drop…so make changes smoothly.
- Embed some wire or hardwood or carbon into the bottom surface of the under nose radome. If the nose gear pin snaps, the skid surface saves the radome.
- No flaps on takeoff, full flaps on downwind to landing.
- READ / SEARCH Hobby Squawk for RF Chokes, Ferrite Chokes and learn! USE THEM!!!! (Amazon has them). I lost an A-10 and an F-4 due to radio glitches before I started using them. No crashes since I started using them….due to radio glitches. HIGH CURRENT ESCs splay out a lot of RF noise and can trip up your receiver = crash.
- See the post above….replace your elevator hardware!!! Stock stuff is too weak. I lost an F-4 due to breakage.
- Consider upgrading the elevator servo. Stock is fine, but a higher quality servo adds peace of mind. I crashed an F-4 when a stock servo failed (repaired and still flying). Hard to beat the MKS HV-69 high torque servo. Upgrading costs $$, but you sleep better. But I fly a lot, so probably wore the stock servo out. LOL. The HV-69 is smaller in size, so some fill work will be needed to the stock mounting cavity.
- She doesn’t have any bad habits.

-GG

GliderGuy - Thank you so much for the pro-tips - I appreciate it and copied it along with the pic for ref... again, thank you!!!

[paulsnapp]

With regards to GliderGuys tip:
Some tips:
- Every one I have flown takes some right aileron trim right out of the box. See photo below. I have owned 3 F-4s….all needed this! Fail to start with this trim and you will be surprised by a hard left roll after lift-off….not fun.

I am curious if anyone else has seen this with their Phantom. Our club has two of these Phantoms and neither required the aileron offset as suggested. I have watched several Utubes and all of them show the ailerons level with the trailing edges. Just curious as I am close to a maiden on mine. Thanks!

[Evan D]

Looking back at pictures of mine it doesn't have any trim like that either...

I agree 100% with his statement to use better elevator pushrod/ linkage and possibly better elevator servo mounting or better servo.
I disagree with no flap take off, I typically use half on take off and half or full landing.
I still chuckle every time I see GG talk about chokes... :)

[GliderGuy]

Hi Paulsnapp….Just passing along my experience WRT aileron. Set them neutral and be watchful for a left bank upon takeoff.

WRT the RF chokes, I saw a NIB plane on a post the other day that had them installed….not an MRC plane. RF chokes are a cheap and easy to install potential safeguard. Use them or not…it is your risk.

Lost an F-4 once and an A-10 twice before installing them. I have not lost a bird since. And Hugh confirms better signal purity with them (frame loss reduction).

After several thousand MiG-29, F-4 and AL37 safe flights, I am going to continue to suggest them.


-GG

[paulsnapp]

Hi Paulsnapp….Just passing along my experience WRT aileron. Set them neutral and be watchful for a left bank upon takeoff.

WRT the RF chokes, I saw a NIB plane on a post the other day that had them installed….not an MRC plane. RF chokes are a cheap and easy to install potential safeguard. Use them or not…it is your risk.

Lost an F-4 once and an A-10 twice before installing them. I have not lost a bird since. And Hugh confirms better signal purity with them (frame loss reduction).

After several thousand MiG-29, F-4 and AL37 safe flights, I am going to continue to suggest them.


-GG

Thanks - and I did install the chokes along with a better elevator servo, a stronger elevator pushrod, a stronger elevator ball link and a replacement nose gear pin that is not so brittle. The first F4 I got from Motion RC had a right wing that was not the same as the left and was angled down at the wing root. They replaced it. Somehow I think their mold process is such that some come out true and others come out with unwanted wing warps that requires the aileron offsets you are seeing. what do you think?

[GliderGuy]

Thanks - and I did install the chokes along with a better elevator servo, a stronger elevator pushrod, a stronger elevator ball link and a replacement nose gear pin that is not so brittle. The first F4 I got from Motion RC had a right wing that was not the same as the left and was angled down at the wing root. They replaced it. Somehow I think their mold process is such that some come out true and others come out with unwanted wing warps that requires the aileron offsets you are seeing. what do you think?

Sounds as good as any reason. The aileron roll on maiden is not violent....just surprising. If you are ready for anything, you'll be in good shape. Have fun...report on how the maiden goes.

-GG

[Hugh Wiedman]

Hi Paulsnapp….Just passing along my experience WRT aileron. Set them neutral and be watchful for a left bank upon takeoff.

WRT the RF chokes, I saw a NIB plane on a post the other day that had them installed….not an MRC plane. RF chokes are a cheap and easy to install potential safeguard. Use them or not…it is your risk.

Lost an F-4 once and an A-10 twice before installing them. I have not lost a bird since. And Hugh confirms better signal purity with them (frame loss reduction).

After several thousand MiG-29, F-4 and AL37 safe flights, I am going to continue to suggest them.


-GG

Yes, I did get a better signal after putting in the RF Chokes on my EDF's. Have them in the last few I've built, 2 F-18's, the E-Flight SU-30 (really helped that one),the A-10 and 2 F-4's. I've also added a remote satellite in all of these and seem to have a good signal now with a low amount of frame losses (typical, as long as there are less than 150 for a 5 minute flight according to Spektrum) and no Holds, which of course are the real scary ones, meaning you've lost signal at some point, it went into a hold, and then reacquired signal.

Where they seemed to help the most was with my "older" AR636 receivers (even with satellites) that have 1 long antennae and one short one at a 45 degree angle. Those receivers are still in my F-4's and with the chokes and satellites, I've got a good signal now. All the others have the newer AR637T's with a satellite that have 2 long diversity antennae on both RX and satellite. Spektrum claims these RX's have improved signal reception over the others and I would agree. I've yet to put the chokes on my Mig 29 (I know, flirting with disaster), but I was able to locate the new 10 channel Spektrum AS3X in a good spot with both antennae going out to the sides and the satellite in the nose. After a bunch of 5 minute flights, the frame losses have always been 30 or less, which is super good, so may not put them in there. They helped tremendously in the SU-30 where I usually had several holds and tons of frame losses, so switched out the RX to the 8 channel new AS3X and put chokes on and it's now good!

As GG suggests, better safe than sorry. Some of the poor signal loss may be from several sources and my better set-ups now may be a result of several things but who knows, as long as it's working!

[Habukeeper]

Hi guys. Great info here. Thanks for that. I have a freewing F-4 coming and I have a Spektrum NX8 radio to use. I also already have a 6s 7000mah 22.2 v 30c battery that I got for my draco. So the question is will the stock ESC for the 6s freewing phantom handle a 7000mah battery and what Spektrum receiver would you guys recommend? Thanks in advanced for Any suggestions.

[GliderGuy]

Hi Habukeeper,

Assuming you have the SPMX70006S30 battery …..which is listed with the Draco;

The F-4 with this battery will likely be sucking wind and may run too high of a battery temperature. If you operate off grass, she may not get into the air without a LONG run.

Battery weight and lower C rating of this battery are gonna be fighting against you. Best consider SMC batteries for the F-4. Example:

https://www.smc-racing.com/index.php...product_id=604


I use Futaba radio gear, so can’t help there.

ESC consideration is voltage….not battery capacity. 6S LiPo is for the F-4 ESC. Battery capacity will influence: weight, size, and time in the air. This bird needs a high C rating (that is a true C). With the above SMC battery….about 3 min flights with throttle management which will leave reserves for go-arounds and will allow for some hot-rodding and acrobatics. Note: Flight times are subjective….just wanted to make sure your mindset is for SHORT flights and not Draco-like times.

Suggest you read some of the many good articles on the SMC website and learn more.

Hugh is smiling

What is your EDF jet experience? If you are jumping from a Draco background to this EDF jet, you are gonna feel like you have a tiger by the tail. Best leave the maiden to an experienced EDF jet pilot if you do not have EDF jet experience.

CAUTION: The F-4 is not a beginner EDF. There are better EDF jets that you can transition from and then get to the F-4. To go from a Draco to the F-4 you may be at risk of going from a bird with trainer-like, high-wing handling characteristics to having a pile of foam pieces within a few seconds.

-GG

[Habukeeper]

Hi gliderguy,

Thanks so much for the advice and the link for the battery. I will most definitely avail myself of that knowledge and one or two of those batteries. Your advice was exactly what I was hoping for. It’s always been my experience that the RC community are some of the best. As for my EDF experience it is exactly as I’m sure my post would imply. Nonexistent. Lol. 😀. I do however plan to get there before I throw sticks on that beautiful model. I do think my modeling skills are equal to the task for assembly. I plan to deck it out in the livery of the 31 TFW 309th blue amu out Of Homestead AFB. You see my best friend of 40+ Years passed away last year. We were both fighter crew chiefs at Homestead and John was actually the assigned dedicated fighter crew chief for acft 463 which the model is well, modeled after. I hadn’t planned on getting an EDF because of the short flight times and the skill I know is required to avoid that pile of styrofoam you talked about. I was also an SR-71 crew chief ,hence the name Habukeeper, and am currently making my way towards retirement from 31+ years in the commercial aviation industry as a A&P tech. I always found it a bit ironic that the real jets were easier to keep air worthy than my models. RC planes have sure changed a great deal since the late 70s. Ok enough of the history lesson. I bought that jet to build in honor of my bud so I’ll do my best to keep it in One piece as long as possible. It may be awhile before I get to fly her but I can wait. I’ll figure out which receiver is best for the spektrum radio and the Phantom. Sorry for the lengthy post. I thought maybe a bit of background might let you know the phantom will be in good hands and I have a pretty good idea of what I’ve gotten myself Into, further research is in order. Lol. I loved that “tiger by the tail” comment, btw. That perfectly describes what I expect. Talk to you later.

[GliderGuy]

Others may chime in and suggest a good first EDF to build flight skills BEFORE you fly the F-4.

These birds are fairly easy to assemble.

Before you begin assembly, take the time to read ALL the posts in this forum. Yep…All 259ish. It will be worth your time. Lots of knowledge here. And, some beefing up in the tail is needed.

Loved your history lesson. Thanks.

Many EDF jets can go 4-5 minutes. But look at it this way….short flights = more flights = better landing skills developed.

Also, don’t shy away from the F-4 when the time comes. She’s a lot of fun to fly…and looks great in the air.

-GG

[Hugh Wiedman]

Hi guys. Great info here. Thanks for that. I have a freewing F-4 coming and I have a Spektrum NX8 radio to use. I also already have a 6s 7000mah 22.2 v 30c battery that I got for my draco. So the question is will the stock ESC for the 6s freewing phantom handle a 7000mah battery and what Spektrum receiver would you guys recommend? Thanks in advanced for Any suggestions.

GliderGuy gives sound advice! I would suggest your first EDF might be something like the Avanti or Vulcan. You'll have to get used to the difference in speed with an EDF versus the Draco and the Avanti is a much more forgiving aircraft that also flies well at slower speeds, but you'll find you can get into a bad orientation much quicker with an an EDF compared to a prop plane. The biggest difference is in landing as you'll have to "find" the perfect speed (too fast and it's back to the repair shop and too slow and it stalls-back to the repair shop) and orientation (nose high touch down) to land in. With that said, the Stinger 90 was my first EDF (and it was a hand full for me at first because I thought I had to fly it at 80% throttle or more and just couldn't visually or mentally keep ahead of it at first) and the F-4 was my second EDF. Landings are generally the #1 areas of mishaps but I see most guys going to their first EDF usually overcontrol the aircraft and they quickly get into a bad orientation, meaning they put too much control surface input in before they are ready to handle it. Low rates are usually a good place to start if you're new to EDF's.

Regarding the battery, yes, I really believe in the SMC's. I fly most of my EDF's on the 6S 6200 40C (weight 814 gr an true 40C) but also occasionally use their 8100 20C (which is actually a true 24C) in the F-16 (same fan & ESC) and even in the F-4 as it weighs only 900 gr but gives an extra minute and a half of flight time.

Regarding the RX, that's kinda like asking "What's your favorite Food"? Mostly personal preference and there is no wrong answer. I personally use Spektrum AS3X RX's exclusively (that's just what I started with and know). So I would recommend the AR637T mounted behind the battery bay with a 12" extension going to a 4651T remote receiver for your best signal (along with some of GG's RF chokes). Assign the FM's to either the gear or flap channel and you can program 2-3 different gain profiles. With mine, I'm around 45/50/55 rate gains only with flaps up and 80/85/90 with flaps deployed as theoretically I'm flying a lot slower with flaps down and therefore there is no oscillation with high rate gains and flaps.

Have someone at your local club who knows these receivers help you program it if possible, however, it really is quite easy to program directly off of your TX and HH has some good tutorials. Since you have an 8 channel TX, you will be able to program the receiver with adjustable gains while flying and with SAFE, if you like (each assigned to a separate knob and switch). Spektrum's RX's internally have a lot more channels than just what is listed. The 6, 8 or 10 channels of their 3 AS3X receivers actually refer to the number of ports you can plug in, but I was told internally they have something like 20 channels (don't ask me to explain this, I just go with the flo). So the F-4 needs a minimum of 6 plug in channels, Throttle/aileron/elevator/rudder/gear/flap. To get adjustable gains, you need a 7th channel (in the TX) and to program SAFE that would be the 8th TX channel. For example, if you had only a 6 channel TX, your gains would be fixed and you would be unable to assign that to a separate knob to adjust in the air. Conversely, if you had a 9 channel TX, you could actually program separate adjustable gains on the ailerons (7th channel) elevator (8th) and rudder (9th) but then couldn't also program SAFE to a separate switch (10th channel). Of course with an IX 20, you could program all kinds of stuff not requiring a plug in port even with a 6 channel RX.

Sorry I have mouth diarrhea today, but hope this helps just a little bit.

Speaking of Homestead AFB:

[Elbee]

[QUOTE=Habukeeper;n333445]Hi guys. Great info here. Thanks for that.QUOTE]

HK, Welcome to Hobby Squawk. Looking forward to inputs, as well. Best, LB

[rcaviator]

I just maidened my F-4 and found the same issue with the ailerons as was posted above. Mine are off 5mm. This the most I've seen. Anyone know of what it takes to correct this??

[GliderGuy]

I just maidened my F-4 and found the same issue with the ailerons as was posted above. Mine are off 5mm. This the most I've seen. Anyone know of what it takes to correct this??

#1 Given it seems to be a somewhat repeated manufacturing issue, you might determine which wing is the offending wing and address it to MRC customer service for a replacement. Set some “true” and stiff wood pieces/dowel rods or carbon rods against the bottom of each wing about 1/2 way out and have these extend a foot or two forward. Measure the distance to the ground or workbench at the forward tips of these. You will find the offending wing or not. There may not be a problem! Make certain she is sitting level on the mains (maybe a bubble level sitting span wise against the flat of the bottom side of the fuselage).
#2 Or…You could add some right rudder trim and back off the amount of aileron trim and re-set the nose gear alignment so it taxis straight and live with it.
#3 Or…You can leave it as is and just fly it. That’s what I do. It doesn’t seem to impact the flight. However, if you acrobat a lot and demand precision, it will mess with your flying.
#4 Or…Carefully align your FFS/elevators. You can use the same stick or rod technique above. If they ARE aligned, you could always misalign them slightly so less aileron trim is needed.

IMPORTANT***Make sure the flaps are aligned identically on both sides when fully up. Since yours seems to be worse than most, I am betting your full flying stabs/elevators are not aligned with each other.

Let us know what you find.

-GG

[Evan D]

Some have found their stabs not even... Also answered in the other thread.

I would also sight down the vertical stab to see how it looks too (not just the rudder center).

[locharrow]

QUOTE=rcaviator;n333579]I just maidened my F-4 and found the same issue with the ailerons as was posted above. Mine are off 5mm. This the most I've seen. Anyone know of what it takes to correct this??[/QUOTE]

Don't put all the blame on malformed wings.....this is what I found when I had a close look at the tail cones.




[

The cone was glued on way off it's correct position, how anyone could do that beats me when the "lock" position is in the mould! I shudder to think what this would do to the thrust line, corrective aileron would be essential but not because of the wing!!

Wee bit of a tidy up for the wing wires at the fan, 1/8th cross grain balsa pressure fit into the recess...

[Elbee]

I just maidened my F-4 and found the same issue with the ailerons as was posted above. Mine are off 5mm. This the most I've seen. Anyone know of what it takes to correct this??

RCA, I agree with both GliderGuy and Evan D, after checking wing tips for 'all square', the elevators would be my second 'go to'. I have not had this issue, but I did mod both of the wingtips with the addition of an aft facing LED housing and light. In the process I taped each outer panel flat to the bench while supporting the inboard section to glue the mounts flush. Might of done something to help presuming there is an OEM warp present. Best, LB

[paulsnapp]

QUOTE=rcaviator;n333579]I just maidened my F-4 and found the same issue with the ailerons as was posted above. Mine are off 5mm. This the most I've seen. Anyone know of what it takes to correct this??

Don't put all the blame on malformed wings.....this is what I found when I had a close look at the tail cones.




[

The cone was glued on way off it's correct position, how anyone could do that beats me when the "lock" position is in the mould! I shudder to think what this would do to the thrust line, corrective aileron would be essential but not because of the wing!!

Wee bit of a tidy up for the wing wires at the fan, 1/8th cross grain balsa pressure fit into the recess...



[/QUOTE]

Not sure what I am looking at. I assume the view is up the tailcone viewed from the rear of the plane? Did you cut off the plastic tail cone in order to see this? If so, is it visible without cutting?

[locharrow]

"Not sure what I am looking at. I assume the view is up the tailcone viewed from the rear of the plane? Did you cut off the plastic tail cone in order to see this? If so, is it visible without cutting?"

Looking up the tail cone I saw and felt a huge lip at the join of the cone to the fuselage. I cut the cone off flush and that left that white crescent shaped part still glued to the fuselage. I took that part out and glued it in the correct position as in the left hand photo then glued on the cone. You can see by the gap between the black dots on the right hand photo how misaligned it was.