Official Freewing 90mm F-4 Phantom II Thread

[davegee]

This may a,already have been discussed, but are there noticeable CG differences with the drop tanks and/or missiles attached? I fly out of Denver (5800" MSL) and after doing several normal flights with and without a gyro clean configuration and no added wing hardware, I added the tanks and later both the tanks and missiles. I noticed that there was a definite pitchup to the plane, like the CG had moved aft. I think this happens with the Freewing A-4 when you put the big wing drop tanks on. Anyway, any thoughts or ideas how to counteract this? I haven't really moved the battery forward yet for testing.
Thanks,
davegee

[RCjetdude]

Centerline tank is finished. Getting close to finally being able to paint this bird.

[quitcherbitchen]

That looks great

[TPS]

Centerline tank in now installed and the cockpit is complete with 3D printed detail and card stock.

Centerline tank seems a little small. The tank was 600 gallons and the wing tanks are 370 gallons. The centerline tank will definitely look bigger and closer to the ground. Just a thought.

[RCjetdude]

It is the proper scale. Both bigger in diameter and longer that the 370's. Photo may be deceiving. That drawing is what it is based on and this photo. The tank is 3" in diameter and 23" long whereas the 370's that come on it are approximately 2-1/4" in diameter and 21" long.

[OV10]

Looks right to me Steve...........but then again it has been 40+ years since I last saw VMFA-333 launching off the USS Nimitz. ;)

[Shirty]

Looks awesome.

[themudduck]

RCJetdude, that picture shows something I hadn't noticed before, the speed brakes with the red paint inside. They look like they're right in front of the flaps. (the F4 had regular flaps like you see in this photo. isn't the amount of deflection remarkable?).




I found this picture of the speed brakes deployed, they are located right in front of the flaps. I had no idea this jet had speed brakes there.
It seems like deploying both at the same time (speed brakes and flaps) might be kind of strange aerodynamically since they're so close to each other. So maybe they didn't do that.

[vduniec]

Thanks for sharing the photos and stories with the group.

I don't know when the position lights were implemented onto the F-4's but throughout the service life of the aircraft, they would have been continuously upgraded as was feasible. You have to be careful with using current flying aircraft and museum articles as references because they are not often refurbished to their original standards and colors that the museum is trying to reflect.

Doing some more research on F-4Ds and went into some old boxes to pull some more photos. First off - my original photo post was not from 1967, but the photo was taken on August 27, 1970 [13th TFS, 432 TRWg] at Udorn. The real BuNo of the aircraft is AF 68 709. Also, I found more pictures that may help with those interested in historical accuracy.
1. File name: F-4D Over Viet Nam (August 1970).jpg Clearer picture of 69 709. Shows full load out. Notice no sparrows in front bays. I seem to recall Dad saying they carried only two in aft bays on strike raids. May have been AAM clean due to bomb load. No jamming pod. Also, no formation lights. Camo helmets and no squadron or wing insignia on port/left side of aircraft. Camo pattern on model is a great match. No "Do Not Paint" nomenclature on nose cone.
2. File name: F-4D Over North Viet Nam.jpg BuNo 68 731 Notice silver around engines and stabilator. That is flat black on inboard section of stabilator. Early jamming pod on port/left inboard station. No Sparrows. Camo or dark painted helmets on crew. Looks like there is some type of repair on port/left intake (white rectangle). Camo pattern still holding true! Also, notice how high the crew members are relative to canopy. I remember Dad talking about they dialed up their seats so they could have the widest view possible. From pictures of the kit - it seems the crews heads are too low.
3. File name: F4-C Vietnam.jpg USAF 4078 Interesting there is no tail code. I do know this is a 13th TFS aircraft stationed at Udorn between 12/1969 and 2/1971. I know this is not a "D" model, but I thought the photo provided a glimpse of a jet that lived a hard life. Look at all of the non-standard paint over repairs. This looks like a crew chief trying to turn a bird around really quickly and used whatever spray paint he had to hide bare metal. Lots of repair lines. Ordinance is older 500 lbs. bombs (non-streamlined). Still no Sparrows. Does have the "Do Not Paint" nomenclature on nose cone. Looks like either camo or silver paint (reflecting tail shadow) on inboard section of port/left stabilator. Notice white tips on port/left wing tank. Looks like the inside starboard/right wing tank is white from this angle. Pilot helmet could be dark. Wizzo helmet is white... and in the right position - opposite of pilot and checking six.
4. File Name: 13th TFS F-4D inspecting battle damage of early F-4E.jpg Notice the squadron insignia of the 13th TFS is on the right/starboard splitter ramp. Both crew have dark helmets in the F-4D. The F-4E is an early variant. The cowling over the Vulcan cannon is not the final form. This version allowed gun expenditure gasses to enter the intakes and cause compressor stalls. The later/final variant has a more pronounced/squared off tip with vents along the bottom of the fairing to direct the discharge gasses along the bottom of the aircraft. The F-4E is from the 34th TFS/388th TFW based out of Korat, Thailand.

[RCjetdude]

Lined the duct with aluminum tape and finished the radio installation. Also got the struts painted. Tomorrow I will start masking and prepping it to paint.

[Helmsman52]

Looking great!! Those cans look killer!

[Aros]

Looking great Steve!

[Dlxpkg2000]

Now C'mon Guys.....Did we expect anything LESS ? Lookin' Great, Steve.!

[janmb]

Freewing F-4 Phantom II Maiden.
Freewing F-4 Phantom 90mm 6S Maiden

---

This jet was a pleasure to maiden. Not a click of trim needed.
I was comfortable flying low during the maiden.
I had 11 flight over the weekend.
Max level speed 105mph Max speed out of dive 120mph (With Missiles, no drop tanks)
I really enjoyed the light airframe. Ability to simply just drop in a 6S pack and wheels up is key for me. The speed was good for me but I did run at 90% a lot of the time. Yes, I would consider upgrading to a Hot 6S system but not right now.....hard to justify. Vertical was ...ok. ...but not near unlimited. I am happy with it overall.
3 mins with average throttle management.
End Voltage 3.8V

Radio: Horus Frsky with X8R RX
Sensors; GPS, Voltage.
Battery: Turnigy Graphene 5000mah 45C
CG 189mm

Thanks, MotionRC!

Brilliant flight and excellent landing - congrats!

[Itgordon00]

Brilliant flight and excellent landing - congrats!

Thanks. I hope to upload a few more vids of the other flights...including the hot landings. ;-)

[tclaridge]

I am not sure the flap deflection in pic from post #1409 is a max setting on the F-4. It may just be the control surface droop with hydraulics off.

[themudduck]

I am not sure the flap deflection in pic from post #1409 is a max setting on the F-4. It may just be the control surface droop with hydraulics off.

that's a good point.


However, here's another picture I found. Looks pretty similar! Maybe not quite as much deflection, but its a lot. (of course it should be mentioned that this doesn't mean its appropriate for the model to use this much flap for landing. I just thought it was remarkable how much deflection I was seeing.) Also - no speed brakes. My guess is that the speedbrakes weren't used with the flaps. I still think its odd that it had both.

[Elbee]

Speed brakes were deployed to control IAS with drag and decelerate quickly as opposed to flaps which assists lift generation allowing stable decreased IAS and increased AOA. An example of speed brake deployment includes matching the speed of another aircraft while forming up after takeoff. Best, LB

[Aros]

Nice info straight from the source. Thanks Elbee!

[themudduck]

Its what I love about Squawk forums, there are people contributing here who have the direct knowledge and experience to enlighten us. Thank you for your service LB!