https://www.youtube.com/watch?v=EXo8ZEg8Jac&feature=youtu.be

Nice flight, Anton! Can you tell us where your CG was for this flight and if you plan to move or leave it as is?

Tom

we set the CG 295mm for the maiden! i think CG 300mm is perfect!

Thanks for confirming the CG. The general consensus is 300mm.

Also, have you experienced any adverse yaw tendencies with this airframe? Apparently the full-scale F-4 had this tendency. I believe the spoilers and asymmetrical aileron throws helped in that regard. Just curious...

I look forward to flying my new Skymaster F-4E later this year!

No adverse yaw with this jet.

Any video, info, or experiences of a twin engine version?

I just moved my CG back to 340mm. I will report on how that goes.

Can anyone tell me what the angle of the tail pipe should be?

If you can please, what should be distance from top of pipe to the bottom of the fuse as a reference point?
Thank you

picture of F-4 tailpipe


http://www.rcuniverse.com/forum/atta...mentid=2153108

Thanks for the pic.
But when I put the pipe in the fuse, the angle of the rear nozzle can change depending where I drill the holes for the bracket. Can I get a few views of the pipe angle in the fuse. And/or the distance from top of the trailing point of the nozzle to the bottom of the fuse?
Greatly appreciate it.
Thank you

ARA,

I believe the pipe lays in the jet with a 5 degree angle downward thrust.

Awesome.
Just to make sure I get my ref point correct, is the turbine at 0 degree and pipe at 5deg downward angle?

Thanks again

That is correct. There should be discussions in the threads that you can search for.

Just scored a SM F-4D NIB. I'm pumped! This is my dream model as I have a little time in the real thing. Now time to start studying the F-4 build threads to make this a really nice flying jet. Plan on a Rhino 200 for blow. As with the real thing there is no substitute for thrust!

Way to go Tom! You're going to love the F-4. Get the chute from Dan Gill, it adds some pizazz! :)

I lost my F-4 over the weekend.

I moved the CG to 340 and it flew really sweet.

I also turned the pipe upside down. This made the phantom stop climbing on throttle.

I also added a P200. Swwweeett power.

The problem: It didn't like full flaps. On my first flight I had a flap servo lead break and I was flying with one flap literally "flapping" in the wind. As can be imagined it flew like absolute crap with the flap deployed and it wouldn't lock into a grove but was flying around fine. Since I didn't know I didn't have a flap, as soon as I deployed landing flaps, it started to sink and roll uncontrollably, this was the clue to quickly pull out the flaps.

As soon as I pulled up the flaps, I had a swweeeeettt landing with the slowest landing roll I've ever had with my phantom.


On the second flight (after fixing the flap lead) it flew locked in with soooooo much power with the P200 with no climbing on power.

After a fantastic flight, I dropped gear, then full flaps and that was when the problems started. It REALLY slowed down and it started to mush out on me. I increased the power and did a full lap with the phantom reacting really mushy.

I DID NOT HEED THE WARNING THE JET WAS TELLING ME.

I even vocalized to my spotter that it was flying "like crap and really mushy with flaps down". All I needed to do was pull up flaps and it would fly great again. Again, I didn't do that.

I thought I could land it. Wrong.

As soon as I turned up wind for final it stalled right out of the sky and unlike the first time, I was unable to reach the flap switch in time and down it went. It was too low and slow.

I was the first one to observe that the SM phantom could not be pulled out of a nose down condition with full flaps with my first phantom in 2005.

Now I'm the first to say:

With CG at 340mm, the phantom will mush and stall very quickly.

If I build another phantom, I will set it up just like this one and never use flaps to land.

As I did not witness any untoward effects of flaps on take off, it seems that less flaps, ie take off flaps, may have been alright.

EDIT:

See here is my original post (#553) on page 23 of this thread and it was in 2007, not 2005.

"Ok after about 50 flights on this phantom, I've discovered two VERY BAD HABITS!!!!!

1. If the flaps are deployed with the nose pointing down, the elevators are completely negated. This causes a very SCARY earthward decent that CANNOT be reversed until the flaps are placed back to neutral.

2. ON BASE AND FINAL, KEEP THE NOSE UP!!! If the nose is allowed to point down with the flaps deployed, there is a critical angle (and I'm sure it is a very small difference in living or dying here) in which the elevator is blanked out by the flaps. (I had 80mm of elevator travel. I had to grind away to give my self this much.)

Once again, if the nose gets to this critical angle, she will NOT respond to your elevator. So keep the nose up, when flaps are deployed.

Raf "

Its unfortunate, I've now lost two Rhino's. But I still love 'em.

R.I.P.

http://i384.photobucket.com/albums/o...ps0d4e030d.jpg

http://i384.photobucket.com/albums/o...ps5d3bc1fb.jpg

Are full flaps blocking the flow of air to the elevators?????

Who knows.

With the CG at 280 mm the flaps make the phantom unrecoverable in a nose down position and with a CG at 340 mm, the flaps quickly mush the elevator.

When I was flying at 300 mm the flap configurations seemed to not affect any "mushiness" of the elevator. I would not let the nose of my phantom drop with full flaps as I already learned that lesson.

My hope with moving the CG to 340mm was for a slower landing at a short field I am now flying at, again, and this was accomplished. However, adding flaps with the CG at 340 mm made the elevator fatally mushy.

"With CG at 340mm, the phantom will mush and stall very quickly."

and if you have the pipe flipped.

It will do the same, if not worse with the pipe right side up.

And it will climb on throttle.

D,

Tam's pipe points WAAAYYY down compared to the stock pipe.

http://i384.photobucket.com/albums/o...s/photo-19.jpg

So give it up on the pipe! :mad: :cool:

Dude! That sucks. I was literally going to pm you to see how the 340 mm cg worked out when I saw your update.

I'm going to give it the old wait and see how the forthcoming 1/5th size rhino looks and performs. Could be spectacular but not sure if I will be able to wait as I'm getting the itch for another flying brick.

Raf,
Sucks to lose a good airframe, and a great looking F-4, it was.

When you say CG is at 340mm, is that in landing configuration, like gear down, half or less fuel in the bag...? Also, landing flaps....what were you using for landing flap setting, the recommended 65deg? I wonder if takeoff flaps or say, no more than 30-40 deg of deflection might be the sweet spot when you're at the ragged edge of 340mm, in the landing pattern.

My first F-4E, a Skymaster, is on the next container ship to CONUS from the factory and I hope to be flying it by early summer. Just trying to absorb what's working for you and what's pushing it. Though I'm willing to move the CG past the 300mm mark, I think I'll be creeping up on the landing flap setting (25deg TO, 65deg, Land). I also want to be able to land at smaller airfields and do it consistently (at ~6000msl).

You also mentioned installing a P200. That could have added another pound or more to your overall weight, no?

Thanks for giving us a thorough flight test and eval on the SM Rhino. Lots of good info, and lessons to heed and learn.

Tom

Keep your CG at 300mm and you'll have nothing to worry about. My last F-4 had a P-200 and CG at 300mm and it flew great. No issues with the flaps down. My current F-4 is at about 305mm with a Kingtech 210 and flies equally well. Both planes are using Tam pipes.

Sorry Raf it was a good looking F-4 :(

Dantley...did you flip the tams pipe around ?? also what is your take off flap setting??
Thx Vin...