Official Freewing 90mm F-15C Eagle Thread

[gooniac33]

Well its warming up here on Cape Cod so I've had the Eagle out about 10 times so far. One thing that puzzled me was the batteries. When I ran a 6S with a 2S the 2S would bleed out energy way faster than the 6S and was only getting about 3mins flight times. When I switched to 2- 5000mah 50C 4S batteries the flight times are now 4:30 mins and both batteries at about 3.7 @ 30% left. I almost lost it on the 6S - 2S combo after the 2S ran out of juice and just ran on the 6S (which it didnt like at all) barely got her back in one piece. So is anyone else having the same issue with the 6S-2S combo?

Whenever you run batteries in series its import that they are the exact same cells and the same age if you want any kind of consistency. The connectors are often overlooked as well. In the end the load doesn't care how the voltage is made so long as it is what the system requires. Any combo should yield the exact same flight times. I choose to use 2 4s packs to make 8s but others use 5s with 3s or 6s with 2s. The age, C and make does matter though!

[Cape Jets]

Whenever you run batteries in series its import that they are the exact same cells and the same age if you want any kind of consistency. The connectors are often overlooked as well. In the end the load doesn't care how the voltage is made so long as it is what the system requires. Any combo should yield the exact same flight times. I choose to use 2 4s packs to make 8s but others use 5s with 3s or 6s with 2s. The age, C and make does matter though!

Yeh I made sure all the batteries where the same age with some break in flights on them and same C ratings on the 6S and 2S. Connections are good and performance was good. But once again after about 6 flights the 2S was draining way too fast. Since I switched to the 2- 4S setup (HRB 5000mah 50C) about a 4-4:30 flight time and both batteries at same percentage and voltage (20-22% @ 3.7-3.8) left in the tank. Not sure why the 2S-6S combo didn't work, but the 2-4S work great.....

[gooniac33]

Yeh I made sure all the batteries where the same age with some break in flights on them and same C ratings on the 6S and 2S. Connections are good and performance was good. But once again after about 6 flights the 2S was draining way too fast. Since I switched to the 2- 4S setup (HRB 5000mah 50C) about a 4-4:30 flight time and both batteries at same percentage and voltage (20-22% @ 3.7-3.8) left in the tank. Not sure why the 2S-6S combo didn't work, but the 2-4S work great.....

Were you using the same series connector?

[Cape Jets]

Were you using the same series connector?

Yes. Same series connector. For both the 2S-6S and 2-4S setups. Flew her again today for 5 flights and used the 2S-6S on first flight and 2S went to 9% and the 6S was at 54% @ 3mins. With good throttle management. Flew the other 4 flights with the 2-4S combo and got a good 4mins and batteries at 25% @ 3.79v. Better results from the 2-4S combo so I'll stick with that combo.
Side note: Do you connect your afterburners to the balance lead before you plug in to the ESC?

[gooniac33]

Yes. Same series connector. For both the 2S-6S and 2-4S setups. Flew her again today for 5 flights and used the 2S-6S on first flight and 2S went to 9% and the 6S was at 54% @ 3mins. With good throttle management. Flew the other 4 flights with the 2-4S combo and got a good 4mins and batteries at 25% @ 3.79v. Better results from the 2-4S combo so I'll stick with that combo.
Side note: Do you connect your afterburners to the balance lead before you plug in to the ESC?

one of the batteries must have a bad connection of some sort. Or one pack has much less internatl resistance than the other... if the 2 4s packs are ok then it has to be the batteries or the connectors on the other set...

You can do it in any order you want. I always plug in the esc first and then the burner.

[Walo]

It came with the nose glued on. Guess I can weight the nose to get it how it needs to be, then glue in some c.f. reinforcement. What glue did you use to attach c.f.?

Hi KS jetflyer
Your problem with the canopy fitting can be fixed by reversing the magnets fuse to canopy. I had the same problem after receiving a replacement canopy only to find out that the magnets were glued in the wrong way so the would push each other away.

[gooniac33]

got some footage of my F-15 with the new FMS 90mm set up and of course showing off the firey booty too

https://youtu.be/1O3RcnWsvSU

[Cape Jets]

got some footage of my F-15 with the new FMS 90mm set up and of course showing off the firey booty too

https://youtu.be/1O3RcnWsvSU

Great Video,,,, Couldn't have picked a better time of day to show off the afterburners.
R u running the FMS 6S-12 Blade? I have the same EDF but seems to lack in power, timing?

[gooniac33]

Great Video,,,, Couldn't have picked a better time of day to show off the afterburners.
R u running the FMS 6S-12 Blade? I have the same EDF but seems to lack in power, timing?

I think its the airframe. I had my own set up in there and it worked great! Adding the FMS and it felt a lil less than what I had before. There is just something about the F-15 that makes it gobble up thrust without gaining much. It does like a strong battery too though... 6s 65C 6000 used in mine for these videos. I am thinking of trying the 8s in here next. My buddy did that and it worked great!

[Dirk.S]

G'day all, from down under. New F15 owner here, just picked up a HP version on sale at a store. Looks like I've got plenty of reading to do!

[davegee]

Hi All: I'm thinking of getting another Freewing F-15C EDF jet. Had one years ago, I think it got damaged on a crash enough that I didn't fly it again. But did enjoy it years ago when they first came out.

I'm trying to come up to speed for the build and settings before I can order one when they come back in stock at MRC.

I was wondering:
1) is there a flap/elevator mix required for this airplane?
2) Seems to be a lot of opinions on the proper CG. Is the book suggestion good enough as a starting point, or do any of you have a "sweet spot" CG in mind for a clean configuration F-15 safe maiden flight?
3) If I wanted to tie in the speedbrake with full flap setting, how would I do that? I have a Spektrum 8 channel receiver and a DX18 transmitter that I will use in this bird.

Thanks for any suggestions. I did look at some build videos, but didn't see details of what I was looking for in them.

cheers

davegee

[AndrewF]

Hey guys, I’m looking at buying one of these from someone. He said it’s set up for 8s, I’m not sure what motor or esc it’s running though. How much of a difference does 8s make with this plane? What are the general characteristics of the plane? Has anyone done a top speed test on 8s?

[davegee]

Hi All: I successfully maidened my F-15C this morning. Temp was about 30 degrees, spitting snow, but I wanted to get this first flight out of the way. Plus, this was an auspicious day to do it: the 74th anniversary of Chuck Yeager's record speed setting flight in his Bell X-1 that "broke" the sound barrier. Before he totally retired from flying, he did fly an F-15 for awhile with the name "Glamorous Glennis" on it, as had been on his X-1. So, I had that going for me for a little extra luck!

Regarding the flight, it went ok, took a lot of the 600 foot runway to take off at 5,000' MSL, and I flew it for 3 minutes, trying to make trim changes, where necessary in various configurations. This will take several flights to finish. It is strictly a stock setup, had a Spektrum 5000 30C battery in it, CG just slightly aft of the manual recommendation.

My only concern, and it was a distracting one, was that the plane exhibited a noticeable wing rocking in almost all configurations with the gear up. Didn't notice it that much in landing configuration and it went into a nice High Alpha attitude for landing. So, nothing damaged, but am concerned about the wing rocking. Might need a gyro.

Does anyone else have this issue with their Freewing 90mm F-15C? If you have any recommendations about a gyro to buy and install, that would be very appreciated. Took a few pics after the maiden. Flew my T-Bird first as the "weather ship" and "warm up ship" for the Eagle.

Thanks,

davegee

[davegee]

I tried a stab at detailing staining of the inner afterburner rings on the F-15C. For this attempt, I used a dark grey pigment powder, a small stiff brush, and a q-tip. I'll revisit it later as I see fit to improve it, but I like it better than just a pure white color. Also, I have ordered a bottle of Alclad II Pale Burnt Metal which gives a slightly gold color to some of the panels underneath the F-15. That, along with some grease and dirt streaking, should improve the look underneath, I hope. I'll attach a couple pics of my still in-progress afterburner exhaust detail and a real F-15, that shows that discolored gold tinted metal underneath the fuse.

[davegee]

Wind was a bit stronger than I wanted to tackle for my second flight on the F-15C Eagle. So, I did some detailing of the hot end underneath of the fuselage. Painted over with an airbrush lightly over the silver with Pale Burnt Metal paint, and then added some browns and blacks dry paint pigments with a brush. Used as a model a photo I found online of a real one. Still more work to do.

[davegee]

Got flights #2 and #3 in today. The last flight was the best of the three I have flown on this plane so far. I hope I can build on that. There is a noticeable "rocking" of the wings left and right in flight, totally controllable, but a bit annoying. Otherwise, it is trimmed up and flies well. Looking into adding the Freewing Gyro in it at some point to hopefully dampen out that slight wing rocking. Everything is set up properly as far as I can tell, including CG. Sets up well to a nose high attitude for landing, as did my F-4. Even on my rough, fairly short runway, it will rollout and stop within about 2/3 of the runway if you put it down near the approach end without brakes installed. Good plane.

davegee

[MartinField]

Anyone have any thoughts on whether the new stock motor (which I think just started selling on Saturday) would be ok in an 8S setup, assuming you upgrade the stock ESC?

[Cape Jets]

I think its the airframe. I had my own set up in there and it worked great! Adding the FMS and it felt a lil less than what I had before. There is just something about the F-15 that makes it gobble up thrust without gaining much. It does like a strong battery too though... 6s 65C 6000 used in mine for these videos. I am thinking of trying the 8s in here next. My buddy did that and it worked great!

Yeh, the FMS EDF stumped me. I thought with the specs for that EDF if would perform better. On anything lower than a 6000mah it was sluggish and flight times were not want I expected. I even tried a 7100mah batt hoping for better times and performance and still no joy....So went back to the Freewing 90mm 12 Blade In-runner and the performance was what I expect from this bird. Flight times are now around 3:30-4 mins with throttle management. These times were achieved with the same 6000mah batts that I only got 3min from the FMS and she performs great with my many 5000mah batts. I do have an 8S system, but that is in my F-16 Thunderbird.

[Cape Jets]

So not happy with the FMS 90mm 12 Blade EDF I've switched to the Freewing 90mm 6S 1835kv inrunner EDF. Thought I had all the settings correct and have used this EDF before in the F-15 with no issues. Well took her out for a initial first flight with the Freewing EDF. Take off speed seemed ok and rotated as usual, but once in the air she was sluggish at best with no thrust. Nose up needed just to keep her in the air long enough to belly land (rather pancake her to the ground). No damage as it was a text book belly land , if that's possible. Inspection on the ground now seemed that she has no thrust at all and tried different batts with same results. Stumped.... When returned home and tested her again it seemed as though she was full thrust again.... Still stumped...The only thing I can think of is the ESC limited the power on take off like a overheat or voltage drop occurred. Like I said earlier have used this EDF in the F-15 before and no issues so any suggestions would be great.

[shamel7od]

What CG are you all finding works best for the FMS 8s upgrade