Official Freewing F/A-18C Hornet 90mm EDF Thread

[Airguardian]

1st, welcome aboard!

Here's my biased opinion, for what it may be worth:

This Hornet is a tricky jet. Get a taste of what it's like first with the EDF. Decide later if you want to commit to a turbine upgrade. It's a lot of money for a quirky model that quickly becomes hard to see as it flies away, so I'd recommend against it.

As for the Zeus... I hate how that thing looks, so my recommendation is to put that X45 (or X52) into something else.

F-22s are great for turbine mods. ^^

[Elbee]

Leighton63,

I agree with jetpltrich 100%.

Finish this as an EDF and make those decisions after you learn this jet.

Post pictures as you are able.

Very interested to see hoe your cockpit turns out.

Welcome to Hobby Squawk; glad to have you onboard, Sir.

Best, LB

[jetpltrich]

G’day everyone,

I’m new to the forum—great to be here. I found you all after picking up the F/A-18C 90mm in Grey Diamonds.

I’ve already been making use of the resources here and printed the detailed cockpit, which is fantastic. I’m planning to finish it in a RAAF-themed paint scheme with custom decals from Callie Graphics.

Originally, I was set on doing a turbine conversion using the Xicoy X45. Back in February I ordered a conversion kit from RC Castle, but I’ve since been told they can’t supply it anymore as the factory in China has stopped producing them (not sure if that’s temporary or permanent). From what I can tell, other suppliers like BigBoy RC and Nova Jets are also out of stock.

At the moment, the only option I’ve found is Grumania Jets. Their bifurcated pipe and mounting hardware look excellent, but by the time you factor in shipping and taxes, it’s getting close to what I paid for the jet itself.

So I’m a bit torn:

• Do I push ahead with the turbine conversion and go with the Grumania setup?
• Or keep it as a ducted fan and put that money towards something like the Turbine Ready Zeus?

I’d really appreciate any advice or experiences you can share. Has anyone here done a turbine conversion on one of these? And are there any alternative suppliers or approaches I might have missed?

Thanks in advance—keen to hear your thoughts!

My two cents... fly it as a ducted fan and determine if it's a candidate for a turbine unit.

Rich

[Leighton63]

G’day everyone,

I’m new to the forum—great to be here. I found you all after picking up the F/A-18C 90mm in Grey Diamonds.

I’ve already been making use of the resources here and printed the detailed cockpit, which is fantastic. I’m planning to finish it in a RAAF-themed paint scheme with custom decals from Callie Graphics.

Originally, I was set on doing a turbine conversion using the Xicoy X45. Back in February I ordered a conversion kit from RC Castle, but I’ve since been told they can’t supply it anymore as the factory in China has stopped producing them (not sure if that’s temporary or permanent). From what I can tell, other suppliers like BigBoy RC and Nova Jets are also out of stock.

At the moment, the only option I’ve found is Grumania Jets. Their bifurcated pipe and mounting hardware look excellent, but by the time you factor in shipping and taxes, it’s getting close to what I paid for the jet itself.

So I’m a bit torn:

• Do I push ahead with the turbine conversion and go with the Grumania setup?
• Or keep it as a ducted fan and put that money towards something like the Turbine Ready Zeus?

I’d really appreciate any advice or experiences you can share. Has anyone here done a turbine conversion on one of these? And are there any alternative suppliers or approaches I might have missed?

Thanks in advance—keen to hear your thoughts!

[Airguardian]

Yep, that works out.

[jetpltrich]

Some gyros do better than others... which one are you using on the Hornet?

Spektrum AR10360T+ DSMX 10 Channel RX. I added a mix so up pitch and down flap work together. It's on a switch and I disable it during highspeed flight and landing. I have yet Fly the F-18 this way, but I have tested it on my YaK-130, and it is amazing how tight the turns are at lower speeds. High gains are selected during slower flight.

Rich

[Airguardian]

Some gyros do better than others... which one are you using on the Hornet?

[jetpltrich]

Correct!
I try to create a conscience about that but I keep running into people that still call them slats all the same, hahaha!

I have duplicated the controls on one of my F-18's much as the real one, even the rudders to assist with pitch, except for the LEF's. The LEF's have components in the way and make constructing them somewhat difficult though I have one spare wing in which I did but not all that satisfied with it. Additionally, the LEF's, along with other controls, work primarily with AOA input. At higher speeds the AOA input is negated. Although I like Full Span flaps due to the slow approach speed, which is augmented by extremely high gyro gain percentages, if the wind is 5mph or higher and not right down the runway it is a real challenge and I've taken a page from my 737 flying days of either a higher approach speed or land with Takeoff flaps.

Rich

[Airguardian]

Are we talking about leading edge devices? My favorite!!

FWIW the full-scale are hinged--no outward movement. They're "leading-edge flaps," not slats.

Correct!
I try to create a conscience about that but I keep running into people that still call them slats all the same, hahaha!

[Elbee]

airmanhurley,

A notable distinction and easier to mod, I would think.

Thank you for the clarification.

Best, LB

[airmanhurley]

Are we talking about leading edge devices? My favorite!!

FWIW the full-scale are hinged--no outward movement. They're "leading-edge flaps," not slats.

[Airguardian]

It's simpler but more critical, I think. The moving LE, will likely be very solid due to being on rails. The hinged leading edge will have pretty high aero loads that could twist the moving surface around and cause sloppy flight, so it should at least have a 'stopper' system so that it can't physically deflect up when sitting at rest.

[Elbee]

Yesterday, 06:47 PM
Originally posted by Elbee View Post
I'm thinking more an open framework cam & pin attached to a separated LE.

This is not my original drawing, different author, in theory the principle would be similar.

Linear servo(s) for deployment; could be mixed with "Flap switch, Throttle setting, both???


That wouldn't be scale for a Hornet though. Hornets (as most modern fighter jets), use leading edge flaps, not slats. They don't leave a gap nor extend forward, only droop down. ;)

As for implementation logic, I'd go for the following:

1 - Droop down with flaps. (Easiest)

2 - G-force induced through telemetry. (The higher the Gs, the more droop, on a ramp that went from 1.2Gs to 4Gs, 0 to 100% deflection, for example. This would need fine tuning though).

3 - Alteratively, gyro controlled (unidirectional) so that when there's pitch up rate, the LEFs droop down).

4 - Pitch input linked (Droop down above certain elevator stick input).

5 - Switchable offset (Drooping down on a 2 or 3 position switch like flaps, but without flaps, for things like sustained high alpha).

Ideally you'd only want them to be actuated as a function of AoA, but estimating AoA on a model aircraft isn't trivial, so the options above cover some of the scenarios of interest.

Airguardian

You are so correct, uncertain what I was thinking.

Thanks for setting me straight.

I would think that dropping the LE would be a simpler design than a moving LE.

Best, LB

[Airguardian]

Here's a little full scale inspiration treat!

[jetpltrich]

I'm using either an SMC 8S HiV 5900 (972 gr) or 4900 (840 gr). On the 4900, 5:30 and on the 5900 over 6:00, but I usually use the 4900 as it flies better with that pack and 60% throttle is great cruising speed, where the 5900 needs a bit more throttle especially on take off and therefor is not as efficient! The 8S power is outstanding for grass take-offs. If I was on asphalt, the 6S most likely would be fine with an SMC HiV 6S 5900 (750gr).

Thanks Hugh, I fly exclusively off pavement with 5000/5700 batteries and I average 5:00 to 5:30 depending on how extreme I get with the flying. What's nice about pavement and my full flap taileron setup is a shorter takeoff with 80% throttle.

Rich

[Hugh Wiedman]

What is your average flight time with the 8S setup?

Rich

I'm using either an SMC 8S HiV 5900 (972 gr) or 4900 (840 gr). On the 4900, 5:30 and on the 5900 over 6:00, but I usually use the 4900 as it flies better with that pack and 60% throttle is great cruising speed, where the 5900 needs a bit more throttle especially on take off and therefor is not as efficient! The 8S power is outstanding for grass take-offs. If I was on asphalt, the 6S most likely would be fine with an SMC HiV 6S 5900 (750gr).

[Airguardian]

I put a lot of work into editing this one, I hope it shows... enjoy!! :D

[jetpltrich]

Agree with Evan D. I've repainted 2 90mm F18's, both originally grey. Suggest you first paint a white primer over everything for better paint adhesion and so your final colors come out true.

Like This: Both are now 8S, sweet! 🤙

What is your average flight time with the 8S setup?

Rich

[Hugh Wiedman]

Hi, I just bought a grey F18 and I want to remove all the decals. I tried using a hair dryer but I haven’t had any success. What do you recommend?

Agree with Evan D. I've repainted 2 90mm F18's, both originally grey. Suggest you first paint a white primer over everything for better paint adhesion and so your final colors come out true.

Like This: Both are now 8S, sweet! 🤙

[Evan D]

Paint over them.