Shaun Evans

Maj,

You did a really fantastic job on this ARF. Do you still have it?

rhklenke

My Feedback: (24)

Dom sold that aircraft when he got out of jets. Do you have questions about it?

Bob

Shaun Evans

Hi,

Upcoming, yes. Going to be building one soon. How is the stock pipe?

rhklenke

My Feedback: (24)

Mine is holding up fine so far (knock on wood...)

Do note that you have to grind away some of the rear hatch area and possibly some of the aft corners of the engine mounts to actually get it into the aircraft though. Dom talks about that earlier in this thread.

I've gotten a bunch of flights on mine this past year, and I love it!

Bob

Shaun Evans

Hi,

Thanks. What electronics do you have in it? Engine?

Chris Nicastro

My Feedback: (3)

Reading back on Dom's flight report about the elevator blanking out with flap deployment I thought it was interesting because the full scale Phantom had some of the same issues.
Project Agile Eagle was a program to further develop the planes maneuverability. As a result the Phantom was more competitive against Migs in air combat. The results of the program can be seen in the mods made to the wings and stab such as reducing the LE Flaps from 3 elements to two and then converting to Slats. On the LE of the stab you can see, on later variants, the inverted fixed Slat Element which boosts the up elevator effectiveness. This was done in direct response to poor elevator performance when the flaps are deployed. Part of the fix involved drooping the ailerons in conjunction with the flaps as well.
Also keep in mind the wing on the F-4 is blown by HP bleed air from the engines compressor section. Pilots must use a higher power setting in order to make use of the additional lift provided by the system. Both the leading and trailing flight surfaces are blown prior to the E model and then the flaps are blown in later models.

So, its not much of a surprise to me that Dom experienced some stab blanking but its curious if this this only observed on the FB model. What about the others, BVM, SM?
I'm going to build an SM kit I have but haven't heard of any issues with it so far.

rhklenke

My Feedback: (24)

You know what guys, I mistook this thread for the one Dom did on his Xtreme Jets F-4. This one is the larger FB F-4, which I believe Dom lost to a radio failure (bad pots in his Futaba 12FG TX). I do recall he, and someone else, reporting problems with elevator response with full flaps. I think the cure was to reduce the full flap throw to less than the manufacturer called for.

After this one, when Dom got back into jets, he got the smaller Xtreme Jets (i.e., SM) F-4 - in the same color scheme. This one is the one that I also have. There have been no reports of elevator blanking with full flaps on this one, and I have not experienced it either.

Sorry for my confusion...

Bob

mikedenilin

My Feedback: (67)

Hi Shaun

George Manning is flying my FB F5 right now. He had made some changes in CG and flap setting. The flap issues were resolved by moving CG backward and now the plane flies very neutral. You might want to call George and ask for the current setting. He is dialing mine in until a sweat spot then I will take over and fly it. .

Mike.

Shaun Evans

Mike,

Do you mean the F-4? That's the one I'll be building soon.

mikedenilin

My Feedback: (67)

Sorry. It's a F4. My cold finger got control of me. Mike.

Brian Mitchell

Hi All
I know this is an old thread, but have one of these nearing completion. Plan to run a Kingtech K140. Will this be enough or am I asking for trouble.
Cheers
Brian

mikedenilin

My Feedback: (67)

140 is more than enough. This jet is designed around 120 size engine. Kingtech 140 generally puts out more thrust than it claims.

Brian Mitchell

Thanks Mike

Brian Mitchell

Hi Guys

Maiden went well, 5 flights so far.



Fuel capacity is huge! Am finding an issue in that after 9 min flight, have used only about 500ml of main tank. As main tank is forward of c/g and saddle tanks behind c/g the c/g moves forward during flight. This means that we are landing with really forward c/g and have noticed reduced elevator authority as a result.

Any suggestions as to a cure?

Could 1) not fill saddle tanks completely and therefore take off with more forward c/g than with full saddle tanks, 2) not use saddle tanks at all, 3) balance plane with fuel in main tank (say 50% full) but this may mean if all tanks full, c/g is a bit aft for takeoff... 4) reduce size of all 3 tanks

Open to ideas..

Cheers
Brian

RCRice

My Feedback: (4)

I just maidened my F-4 today and all went well except the main landing gear would not retract. It does cycle on the ground in the stand but will not retract in the air. I'm noticing that the gear doors are mounted on the strut and angle out a bit. I'm assuming that this can cause additional wind resistance preventing the gear from moving. Has anyone else experienced this? If so, what was your solution. In trying to change the angle of the gear door by turning the strut then prevents them from retracting flush against the wing. Any suggestions? Checked for air leaks and there were none.

dubd

Make sure the door connected to the strut isn't binding with the small door above it.

HiCurrent

Try to wet the cylinder shaft with oil. I found the shaft very dry. Also I retract immediately as soon as the wheels are off the ground

RCRice

My Feedback: (4)

I worked on this quite a bit but still no luck. Works great on the stand. I'm running with a K-180 and I'm still thinking the gear door attached to the strut is holding it out. They both angle out a bit. It looked like they started to retract but didn't finish the cycle. Next flight I will remove doors to see if that helps.

rhklenke

My Feedback: (24)

Do you have any kind of restriction or adjustment that slows down the gear? If so, I would remove that so that the gear moves up as fast as possible. You can slow them down on extension, but I've found that retraction is most reliable when the gear go as fast as possible. On retraction, you're always working against gravity (and some extra G's too if your pulling up as you retract) and usually fighting the airstream as well. On extension, both gravity and the airstream usually help you.

Bob

RCRice

My Feedback: (4)

No restrictors in the airlines. I've even tried over pressurizing. I think it helped but the gear didn't retract completely and fell back down. I want to see how it does without the wheel pants. If that works i'll probably go to a high flow air valve.

Bob