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        Discussion E-Flite F-4 Phantom DF32

#1 bmiller Jun 04, 2012 02:14 AM

E-Flite F-4 Phantom DF32
2 Attachment(s)
Beautiful but Difficult to fly.

#2 bmiller Jun 04, 2012 03:06 AM

Assembled easily, I won't say build., a true ARF.
HS82mg, bigger HS225mg on elevator, ICE100, proBEC, stock eflite fan/motor.
For the maiden I set controls per manual except more elevator w/40% expo as someone reported they used 40%..
No dual rates were set as I always use high rates trusting my thumbs to keep things in check.
Took off perfect, didn't need any trim. elevator was horribly slow reacting but I kept flying.
Big loop, rolls quick with speed, really slow(dangerously) at lower speeds.
As I pulled back for a high speed diving run dwnwind it suddenly went vertical and I had no control despite moving all controls. it came out flat and level at the top and I regained control. Not knowing what caused that I decided to land. Quickly turned to final, wheels down and full flaps, but was too high and fast. Decided to go around, Kept it at 50ft at 1/2 throttle and turned dwnwind with whells and full flaps still down, BIG Mistake.
Controls turned to mush but it was straight and not losing too much altitude.
A crosswind gust caught it and flipped it 90 degrees to the right. I immediately applied full left aileron with little effect! Losing altitude quickly now it slowly came back upright but by then it was behind and below the bushes so I just shut it off and kept the nose up.
A sickening fglass breaking sound behind the bushes. Nose shattered back to the intakes. The nose wheel strut had caught the bushes first and ripped the entire nose apart. If you're crashing in the bushes get the wheels back up!

#3 bmiller Jun 04, 2012 03:28 AM

4 Attachment(s)
Did the humpty dumpty on the damage w/CA and kicker. Cut a new wood deck/retract mount, new retract and steering servo. looks pretty good.
2nd flt. removed all expo off elevator.
Took off, instantly had to apply left aileron then as the speed came up it tracked straight.
Pulled around and once again it went vertical with no control, it leveled out at the top and I regained control. Now I'm freaking out, want to land so I get it around on final, wheels down NO FLAPS this time, Comes in easily and lands.
Look over can't find anything wrong and don't understand why it goes out of control.
I increase elevator travel thinking it needs more to keep control.
Take off 3rd flight, climbs easily with 7S I turn left and pull elevator to come back for a hispeed run and again it does that uncontrollable vertical. this time it doesn't come out level, stalls out and snap spins down 100ft into the ground. Lipo explodes into flames.
This time fuse not repairable but surprisingly everything else is good.
Tam offers to sell spare fuse so I meet him at Button Willow fly my F-16 and bring back new fuse.

#4 bmiller Jun 04, 2012 03:48 AM

Thought about the uncontrolled verticals and realized its caused by too much elevator travel. Rebuilt F-4 all perfect again. Lowered bat tray so now I can fit cockpit/pilots AND 7S 5000s.
Elevator reduced to 2mm more than mid rates and 10%expo. Max flaps set to mid rate.
4th flight 6S. Wow flys so much better with no weird verticals now I got something I can work with.
Elevator still lagging behind my inputs but very flyable. Land no flaps, no problems.
5th flight. 7S 5000s, 0% expo, Elevator pretty good now ,would prefer a quicker initial response though..
7S is fast, seems a tad slower then my same setup H32 but not sure. One diving downwind blast was well over 150mph though. Aileron expo increased from 10% to 20%made them less twitchy.
Nose wants to point up in turns somewhat, I used some rudder to help it turn better. I didn't have any differential setup on it. Next time it will.
Full flaps set at midrate for landing...not at all effective, will increase to 13mm. However the ailerons worked better. Watch out for much reduced aileron effect with flaps down.

#5 bmiller Jun 04, 2012 03:57 AM

Last weekend there was a carnival at the park and its overcast.
Runways clear but final approach must be made with a short sharp turn as the ferris wheel is blocking my normal approach. Plus lots of people walking around.
I didn't want to risk my not completely sorted out F-4 with all that and the grey skies.
I can wait til next week.
Need some color on this F-4, too hard to see faraway. Probably paint the outer wings red for next week.

#6 bmiller Jun 07, 2012 07:15 PM

2 Attachment(s)
Added dayglo orange to the leading edges.
Hopefully it's all it needs without ruining the scale effect too badly.

#7 bmiller Jun 09, 2012 10:23 PM

2 flights, dayglo ineffective, dayglo in the exhaust exits almost killed the jet on 2nd t/o.
Aborted at last instant as it was barely accelerating at wot as it rolled past me. the dayglo was getting blown off by the efflux and blocking the exits. Ripped out of there and performance restored so took off on 2nd flight. Expo on elevator now set -5% and it finally feels correct.

#8 jzanutto Jun 10, 2012 11:48 PM

looks nice, its really too scale. Being an 8 year F-4 guy, the real Phantom has 3 channels of STAB AUG (stability augmentation). An early version of what the modern day fighters have. The Phantom is not controllable without it. a gyro system like that of helicopters would be really necessary.

you cant get a real phantom behind the power curve, and a model is even worse since that scale wing doesnt supply adequate lift at low speed

#9 jzanutto Jun 10, 2012 11:51 PM

with all that being said, I think I'd like one

#10 bmiller Jun 11, 2012 02:14 AM

It's a real beauty.:) Fly with the listed midrates and you won't lose it like I did.
I like that it's definitely for the experienced EDF flyer.
The wing itself seems fine at slow speed, but the small ailerons get ineffective with full flaps and the outer wings are prone to crosswinds, not the greatest situation when I'm trying to land in windy conditions.

#11 bmiller Jul 02, 2012 01:36 AM

Ok I'm slowly getting the better of this thing!
Aileron expo at 25% helped alot, feels normal like the elevator now.
Polarized sunglasses has made the biggest difference. Much easier to see it's attitude at distance and I can now see the dayglo on the leading edges as well.
Used new 7S GenAce 4000s and moved the CG back on todays flight and it flew fantastic as well as landed much better. Usually I run out of elevator travel, this time I still had some at touchdown.
Also found and fixed an issue with the intake ducts. Fan suction was sucking the inner walls in since I had removed the rear batt tray brace to lower the tray to the floor. It was so bad you could stick a finger in the V of the ducts and touch the spinner. Epoxied a popsicle stick to each duct and epoxied the top where the ducts meet. Now the gap is 1/8inch and doesn't change. End result was a better sounding fan with a significant boost in thrust.
E-metered the 7S setup at 2400W 90A. The F-4 flys great at this power level!

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