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

[Carlbrainiac]

Just another thought. Its obvious to check c of g but have you also checked the left/right balance? I think if we are adding ordinance it is important to check that each item is as balanced as best it can be. All well and good it being balanced for c of g but then if its particularly heavy on one side for one reason or another then that wont help. Also if the missiles have fins worth looking to ensure those direct air flow correctly etc.

[Bobaroo]

As the 'JanMan' has suggested, those SlotGroove attachments may be inadequate for this application. Especially if there is a lot of Weight involved and that tank is allowed to wiggle around under there. These Tanks, Cameras, Missiles, etc... act like airfoils to some extent and if they're not mounted rigidly, they are going to impart some Airfoil Type forces into your Jet. Airflow through the 'Cheater' as you said, is not a concern. The tank can usually be positioned to actually mask that unsightly grate under there and that is one of it's advantages.

The F-4 and A-4 Tanks have a Deep Channel that the magnetic pylon mount goes in and gets ''locked' into very firmly. A mount that holds the Ord Very Rigid and Secure with zero lateral variance is preferred on the lighter stuff.... Something like that is Required for this CLTank business. GL

[Bobaroo]

Just another thought. Its obvious to check c of g but have you also checked the left/right balance? I think if we are adding ordinance it is important to check that each item is as balanced as best it can be. All well and good it being balanced for c of g but then if its particularly heavy on one side for one reason or another then that wont help. Also if the missiles have fins worth looking to ensure those direct air flow correctly etc.

Lateral Balance and Asymmetrical Load-Out can be overcome with 'Trim'. In fact, there is nearly always a Trim adjustment required on my stuff with all the various loads. The FW F-4 seems to be the least affected by 'Stuff' hanging off it. Others who have done these mods may attest to that as well. Cameras on the Outboard Stations are big 'TrimHogs' ... and this 'PaveKnife' Pod and some other ECM Countermeasures Pods are tricky too. This one due to It's Shape, imparts a nasty yet predictable Roll at higher Airspeed !!! I would encourage everyone to Embrace these Ord challenges and Load-Out your combat Jets !! GL

[janmb]

Lateral Balance and Asymmetrical Load-Out can be overcome with 'Trim'. In fact, there is nearly always a Trim adjustment required on my stuff with all the various loads.

Well, yes and no. Meaning mostly no lol.

Just like a poor CG can never truly be fixed by trimming, nor can any other imbalance. Sure, it can be trimmed at any one speed, but as soon as you go slower or faster, the culprit resurfaces immediately.

[Carlbrainiac]

Well, yes and no. Meaning mostly no lol.

Just like a poor CG can never truly be fixed by trimming, nor can any other imbalance. Sure, it can be trimmed at any one speed, but as soon as you go slower or faster, the culprit resurfaces immediately.

Yup agree. I set up all my models balanced across all axis. In my opinion then if a model needs a lot of trimming then something is wrong and more often than not its balance.

[Bobaroo]

Clearly you two Guyz have this Asymmetrical Load-Out stuff all figured out !!! Guess I'm 'OuttaHere'. GL . Hahahahaha

[DCORSAIR]

Okay, just finished flying and this is my flight report. I used some of the ordinance from my A-10, decided to fly the A-10 this morning because it's so easy to slip off the ordinance and slide it on the F-18. The posted pics show what I tried and all is well with anything mounted on the wings, but I went ahead and tried one bomb from the A-10 mounted to the belly as if it was a drop tank, well it didn't yaw to the right on take off like the big tank did, but it did fly unstable and you can tell something is not right and I had to put down trim for level flight, then I mounted the pods and all that, tried different combinations, so with all this I found that anything mounted under the belly between the gear and forward, it does not like it, and everytime I added something different I had to add down trim because whatever is hanging underneath pushes the nose up, and by the way my F-18 is trimmed very well, I mean no aileron trim at all, all surfaces are dead straight except the elevator trim which I'm working on to get it less, over all the F-18 flies very well and scale.

[JLambCWU]

Word of warning guys!!

I haven't seen anyone else besides James from MRC who crashed his F-18 on maiden have something mounted on the belly of the F-18, today I tried a drop tank but only after I put four flights on it, including the maiden, then I mounted the drop tank on the 5th flight. CG was checked and perfect, it took off and instantly I knew I was in trouble, it yawed to the right really bad, ailerons weren't turning it hardly at all, kicked in rudder and got it to turn left, it almost rolled over on it's side and crashed a couple of times just like James did with his, but mine never got inverted, ailerons by them selves could not hold it straight, then I realized that rudder was the only way I was going to fly and land this wild Hornet, gear was down already, and with almost full left aileron and using rudders, I was able to bring it around and land it without a scratch, I couldn't use flaps because I couldn't let go of the sticks to put them down, glad I didn't use flaps, no telling what would have happened, anyway it's in one piece, the next flight I removed the drop tank and it flew straight and level like the first four flights, so be warned if you're going to try a drop tank. Here it is before the wild flight with the drop tank mounted, and here it is now after I weathered it up, drop tank will be for display only, going to try some ordinace next time and see how that goes. I might have over did it on the weathering but this is my first attempt so lets not be to critical...........lol.

So be ready is all I can say if your going to try a drop tank, my tank is from the FW F-15 and my mount from the F-16, it is mounted nice and straight, anyone with an explanation on why my drop tank caused this out of control flight????

I haven’t flown my Hornet with the centerline drop tank yet. I however have 3-D printed and flown centerline tanks on the 90 and 70 MM F-16s. It looks like your center pylon may be too tall/sticking down too far. This would cause a Yaw/Rudder moment about the CG in that area, which would be very strong in that location. Shorten it up so that it is only 3/8 of an inch tall or less and it should fly a lot better.

[DCORSAIR]

I haven’t flown my Hornet with the centerline drop tank yet. I however have 3-D printed and flown centerline tanks on the 90 and 70 MM F-16s. It looks like your center pylon may be too tall/sticking down too far. This would cause a Yaw/Rudder moment about the CG in that area, which would be very strong in that location. Shorten it up so that it is only 3/8 of an inch tall or less and it should fly a lot better.

Oh okay, thank you for the tip, as I posted, I tried one bomb as well from the A-10 which is way smaller and I could still feel something weird in my flight controls versus without, my main reason for even posting this was to warn others who are about to try a large centerline tank to be aware of what might happen. Don't think I'm going to try anything else under there right now until I hear and see a video of someone flying with a scale centerline drop tank. I'm not saying it won't fly with one but in my case it did not work with the tank I used, I thought it looked great and very scale looking, so no big deal, two sidewinders on the wing tips is all good for me.

[RCjetdude]

Doesn't the FMS 70mm have a centerline tank?

[DCORSAIR]

Doesn't the FMS 70mm have a centerline tank?

Yes, I just checked it out and I found a guy flying with the drop tank on the FMS F-18, it was mounted about like I had mine and looks to fly just fine. I might try mounting it up closer to the fuselage and a stronger mount like someone suggested, or wait until someone else tries it with the results.

[fredmdbud]

Yes, I just checked it out and I found a guy flying with the drop tank on the FMS F-18, it was mounted about like I had mine and looks to fly just fine. I might try mounting it up closer to the fuselage and a stronger mount like someone suggested, or wait until someone else tries it with the results.

Do you think there might be some play with the centerline pylon mount, causing the tank to sway a bit?

[tengarang]

the positioning of a centerline tank and its relative scale to the parent aircraft especially on small wingspan swept wing is critical. Its probably why FW didnt include this in their design in the first place.

The relationship of dynamics airflow on the bottom side with respect to the top side is characteristically changed if not properly positioned.

another way to picture this is adding a sphere near or close to the leading edge of the wing at the center of the fuse. The head winds would categorically cancel out top and bottom side resulting in massive control loss of the horizontal plane

[DCORSAIR]

Thanks guys for all the input on this, I do belive like others have said already, my tank is mounted maybe a little to low and not strong enough at the attachment point possibly, not going to mess with it anymore, I actually like to fly it clean except for the wingtip sidewinders, I did enough testing now to know it flies better with nothing attached to it at all really, now I'm camparing it to my F-16, A-4, F-4, Eurofighter, Mig 21, Yak 130, and the A-10, they all fly fine loaded up, except the F-16, it hates the wing tanks mounted, flies weird so I leave them off, so I will do the same on the F-18, done with this subject guys but be aware if you do mount a centerline tank on your F-18 it could be a handful or could fly just fine for those that know what they are doing............

[Bobaroo]

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[tengarang]

Thanks guys for all the input on this, I do belive like others have said already, my tank is mounted maybe a little to low and not strong enough at the attachment point possibly, not going to mess with it anymore, I actually like to fly it clean except for the wingtip sidewinders, I did enough testing now to know it flies better with nothing attached to it at all really, now I'm camparing it to my F-16, A-4, F-4, Eurofighter, Mig 21, Yak 130, and the A-10, they all fly fine loaded up, except the F-16, it hates the wing tanks mounted, flies weird so I leave them off, so I will do the same on the F-18, done with this subject guys but be aware if you do mount a centerline tank on your F-18 it could be a handful or could fly just fine for those that know what they are doing............

awesome,

and now that you mention it I do see people already addressing this before my post, so goes to show I didn't read before posting. my bad.

this brings up an opportunity for raising the topic, how much R&D essentially over 90% of their effort goes into research of how much repositioning in terms of micrometers external load outs or even more insane as dynamic internal loadouts like the stealth planes are carried as weapons are deployed. To the public its just a missile or an extra part sticking out.

How these parts integrated interaction with the aircraft in the fluid of air is really a piece of work much under-appreciated, as most of the interested public is more concerned about other technical advancements of the parent aircraft.

[tengarang]

i want to note the wing ordinance is not going to be nearly as significant in terms of the impact of the aircraft's aerodynamic behavior when positioned at the center underside or top side

[Bobaroo]

http://youtu.be/mtGBrIYyIVk

[Bobaroo]

[RCjetdude]

Got some lighting done. Formation lights are next on the agenda. Contemplating an operational arresting hook.