Official Freewing 90mm F-15C Eagle Thread

[guylookingup]

Guys,

A couple of real basic questions...

I received my F-15 yesterday and pretty much have it assembled except for a couple items:

1) What are the two foam (silver) "pyramids" that are in the box? Looks like a left and right item for something...just don't see anything in the instruction manual, They are about 3 inches tall and generally triangular in shape.

2) Is there clever method of getting the vertical stab/rudders on? The rudder servo and light connectors are causing me some problems. I am trying to get the connectors down into the cavity on the fuselage but having a difficult time of it.

Other than that, I am very happy with the overall appearance and assembly of the jet. Looks like a lot of fun to fly from the videos all of you have posted!

Thanks for any help or suggestions.

[crxmanpat]

Those two triangles go on the rear next to the exhaust nozzles. If you look at the pic on Page 2 of the manual, you'll see them sticking out the back of the plane. There is no step in the manual that shows their installation. I think originally they were supposed to already be glued on, but the shipping box prohibited it.

As for the verticals, that was the hardest part of the build. You just have to work everything into the channel carefully to get them to fully seat. Tweezers or small needle nose pliers help here.

[guylookingup]

crxmanpat,

Thanks for the information! I'll keep struggling with getting the vert. stab on knowing that others are sharing my misery! :-)

Also, thanks for the information on the "pyramids!

[DCORSAIR]

For the verticals, I just went in with a xacto knife and very carefully cut some of the foam out to the rear, if you do it right it will make a small channel for the wires to be pushed into when installing the verticals, and on my very first F-15 those small triangle looking pieces were already on but were broken in shipping so I think to many people found them broken also from shipping, so on my second F-15 I noticed I had to glue them on myself, they go on the rear in between the elev. and exhaust nozzles, you just have to line them up the best you can, there is a left and a right one, directions don't tell you which way they go.

[guylookingup]

DCORSAIR,

Thanks also for the input. I watched one of the videos and noticed the "pyramids" near the rear of the exhausts. Now that I know that the vert stabs are a bit more of a struggle than I knew, I'll go ahead and make some recesses in the foam as you suggest. Thanks again for the help guys!

[gooniac33]

more f-15 flights over the last couple weeks. Here are a couple vids....

[iridium]

Curious if anyone has had issues with the UBEC? I am using a lemonrx 10 channel receiver and diversity satellite. I performed a range test and various bench tests and everything checked out. However, today when I went to take off, I went to full throttle and the system went into failsafe mode.

Oddly, when I brought the plane back to the bench I was able to do full throttle tests with no problem.

Anyway, I started to wonder if the ubec wasn't supplying the receiver with enough power during takeoff. The lemonrx is rated for 3.45 volts, so I should be fine there.

Could RF noise from the power system be causing receiver issues? Other thoughts?

Thanks!

[Kenny d]

I'm thinking of adding an ADMIRAL RX600SP 6-CHANNEL DSMX With gyro. The plane because of it's short wing gives me problems on landings. especially in a little wind. Has anyone used one yet? Thanks for the input

[2010vette]

You guys flying the F15 how long of a runway you need to take it off?
I have about 190 feet of runway. I was wondering if that will be enough? Thanks James

[JLambCWU]

Would somebody be willing to measure the length of the AIM-9 sidewinders for me? I’m turning my 70 mm hawk into a desert hawk and arming it. I got the rails for the 70 mm F-16 to put on the wing tip, I just need to know which armament kit to order. The rails are slightly too long at 9”s

[gooniac33]

You guys flying the F15 how long of a runway you need to take it off?
I have about 190 feet of runway. I was wondering if that will be enough? Thanks James

If the plane is stock you will need at least that much to get airborne. I use take off flaps to get in the air quickly and have even used full flaps to get off the ground fast as well. You may be pushing the limit of your runway though....

[fhhuber]

You guys flying the F15 how long of a runway you need to take it off?
I have about 190 feet of runway. I was wondering if that will be enough? Thanks James

Heavy EDFs need care to get airborne from short runways and even then they may not make it.

Tie a fish scale to the tail of the model and slowly increase throttle. You will find some throttle position where the pull suddenly drops off as you advance throttle. That is your maximum static thrust.
You may be able to get off the ground in less runway by not advancing the throttle beyond that for the first half of the runway and then just using about half the remaining throttle over the rest of the runway.

Small flap deflection mostly improves lift. Large flap deflection mostly increases drag. Generally, don't go beyond about 25 deg flaps on takeoff as the drag penalty will be worse than the benefit from added lift.
One of the methods of slowing servo response is a good idea on flaps. Especially pulling the flaps up if done too rapidly can get you in trouble by removing too much lift before you can gain airspeed from the reduced drag.

Its better to practice you short field procedures on a runway with plenty of length. Learn what lets you take off in the shortest run and how to put the airplane down for the shortest landing roll-out where its not a matter of success vs destruction.

[ColtPilot]

Hey guys, here is a new F-15 paint scheme fresh out of the paint shop from the Air Force. I'm sure Callie Graphics would do a great job on this for someone so inclined.

[MikeT]

https://www.youtube.com/watch?v=2OHtAPTVPkE

Very Cool.

Mike

[duke]

HI All,

I'm new to this site. Thinking about a F15 for Christmas(for me). I was wondering if there is a program available for Spec DX9 Transmitter?
I am thinking of putting a JF 90mm that runs on 10s, Is there room for to 5s-5000mah's(45x42x140). respond here or email at --

marineconsltmgmt@yahoo.com

Thx for any help,
Duke

[ColtPilot]

Since there is a program module already in the jet, the only thing you would need to do is program in some expo to your flying style. It's one of the easiest flying jets, you'll like it.

[MikeT]

HI All,

I'm new to this site. Thinking about a F15 for Christmas(for me). I was wondering if there is a program available for Spec DX9 Transmitter?
I am thinking of putting a JF 90mm that runs on 10s, Is there room for to 5s-5000mah's(45x42x140). respond here or email at --

marineconsltmgmt@yahoo.com

Thx for any help,
Duke

I'm running 8S and it's tough to fit anything more than 4400 ma batteries in there. 10s might be a really tight fit.

Mike

[Alpha]

Hi Duke, long time member, I see! Welcome!

We don't provide an official DX9 .SPK file (setup file) for this aircraft. But the F-15 really is quite straightforward. If you're stuffing a 10s JetFan setups, I'm certain the radio setup will be easy for you. Someone here may have an .SPK file they can post, which would be nice but I would still of course recommend you tweak it for your preferred amount of expo, and double-check the control surface direction. The manual available for download here shows our recommended throws: https://www.motionrc.com/products/fr...ce-edf-jet-pnp


As for the JetFan setup itself, I ran 8s 5000 in this F-15, and they *just* fit. I cannot imagine how a 10s 5000 pack would fit, accommodating for wire length as well. The canopy floor is right above my 8s 5000 pack. Frankly speaking, all of Freewing jets I've flown on 10s haven't been massively better than 8s. These foamies will hit a drag wall, not to mention weight and loads throughout the airframe that we didn't design it for. I think many people who have tried for example the Stinger 90 or T-45 on 10s would agree that 8s is the peak of the diminishing returns graph.

[MikeT]

Hi Duke, long time member, I see! Welcome!



As for the JetFan setup itself, I ran 8s 5000 in this F-15, and they *just* fit.

What KV motor are you running in your JetFan?

Mike

[duke]

I was thinking about the 700-68-1400, however after Alpha's post I'm rethinking this 10s setup.