jofunk

I made a tray to mount the tees.


This is about as neat as it will get in the rear bay. The tray helps keep the hose out of the way. There is a little extra hose so things can be removed,and worked on.


I ran the retracts up and down manually. They will crush something if it is in the way....The gray tees that came with the controller did something weird under pressure. The release collars look like they hyperextended.It may be normal but I didn't like it and replaced them with Clippard tees.
Thanks for the heads up Edgar. I will check it out.

jofunk

I modified the bottle replace the cylinders so i could run the pump and fill the lines


The nose gear light runs on a single AA battery so I modified a holder for one battery


The on off switch for the light will be the battery. put one in for light on. The light needs to be on for the first flight to do Vladimirs gear justice.



I need to do a few more things on the bottom and then it can be flipped onto the gear.

jofunk

the brake lines fit perfectly through the lug on the landing gear.


The lines that touch the pump got a silicone sleeve to insulate them. Im not sure how hot the pump motor will get


I made a little vented pad for the receiver to sit on. I also made a little tree to keep the receiver antenna at a right angle.


This is everything installed on the tray. It is very busy but everything fits well. The tray holds the tanks in place. It is all close to the CG.

jofunk

I took my retract controller apart to check if I a questionable capacitor. I don't see a capacitor. But I do see a lot of differences in the two controllers. I guess I will give this a try and see if it works. Thanks for the heads up Edgar

jofunk

Here is a better pic. Unless the component in question is the one laying down.

invertmast

My Feedback: (23)

jofunk

I proped the plane up on some stands to balance it. Things were way too unstable


So I hung it from the ceiling. My hunch about the CG being close was correct. With the gear down the plane hung on the CG with a slight nose down attitude at 29% MAC.


I cycled the gear up when it was hanging and the nose pitched down a bit more. I was afraid to walk away from it while it was hanging on the ropes.

jofunk

As far as the UMS controller goes. When I was priming the system upside down on the table I cycled the gear with a 2S LiFe direct to the pump. When I was balancing the plane on the horses I hooked up the controller and cycled the gear up and down six times. Everything seemed to work fine. I am going to do a bunch more cycles with the plane in different attitudes to eliminate any air. If the controller takes a S#!T Ill put up a post.

jofunk

I put a very short tail heavy flight on the Vigilante today. It didn't end so well with a baptism of Kentucky dirt. The plane is not gone but is really banged up. The landing gear got it the worst. The nose got it pretty bad. The fuse got a little banged up. The wings, hoz. stabs and vertical are fine. When I get it back on the workbench I will post some pix.

turbofixer

Sorry to hear that Joe. Can you post a top view showing your CG location? I would like to compare to where my plans show mine should be. There was a guy that posted a Viggy on RCG that also was tail heavy on maiden flight. he did manage to get it back down with little damage

causeitflies

sysiek

My Feedback: (176)

Some good pictures.

ps2727

jofunk

Thanks for the thoughts guys......... TF when I get a wing back down in the basement I will snap a pic of the CG. You can see the 29% CG mark in the last picture on the side of the access above the fuel pump. The pictures are out of order but the fun started in the first picture where I am holding almost full down. It all happened in the length of a runway stripe. I may have been as much as a half a foot off on the CG. My fault for using a safe straight wing CG location on a delta/swept wing. I will make a two foot wingspan glider of the plane to throw around and get a better idea of the correct CG. Thanks for the pictures Sebastian.

jofunk

Here is the bottom of the fuse. It hit somewhat flat and the formers pushed through the skin along the bottom right.


The front with the nose broken off. The mating plates still firmly attached.


Here is the worst part. Vladimir landing gear. It really took a beating.


When the cylinder got rammed on impact it created a aneurysm in the hydraulic line. I warmed this area to bend the line when I installed it. Even though I couldn't see this connection I know it was not operating like this, because it is paper thin. It took me a while to figure this one out.

jofunk

Here are the holes cleaned up.


Filling them was like patching a hole in drywall.


And a little glass to harden everything up.

jofunk

Here is a shrunken down print of what I built the plane from. The wingspan is two feet. I will cut out a plan view from foam and throw it around. That CG mark the 29% CG location I used.


And the side view.

jescardin

My Feedback: (1)

Joe, 29% CG is not very recommended for maiden -even if correctly calculated- and much less for a jet!

My general CG preference is 25% on maidens, the same for a warbird or a sedate biplane. I only accept going back as much as 27-28% if I find balance weight excessive for just a few millimeters and NEVER, NEVER go back of 30%.

That is my procedure regarding propeller planes and gliders but for jets I even go forward. I must reckon I do not have the experience nor have flown so many different jet designs as other RC Universe members, but I have always took the advice on jets CG explained on the classic book "Ducted Fans for Model Jets". There expertise David James explains that with jets and due to long forward fuselages and air inlet surfaces greatly adding to lift, CG must be well forward relative to that of classic planes, giving figures between 15-20% MAC.

I would suggest you to comment with other jet designers -not to "just" RTF pilots as they just go for the instruction manual CG!- about it, but if you do not find a safe guidance, you may always go for 25% MAC but correctly calculated over the plans and then checked on the foam glider.

I offer, if you wish, to help calculating the CG via a Cad program and sending you the results for 20% and 25% on a pdf sheet. I would only need a vertical image of the plan view and an exact measure for accurate scaling up the drawing.

Best Regards,

jescardin

My Feedback: (1)

As it is a long out-of print book from a defunct publisher, I think I do not break any rule nor law for showing the C.G. related pages as help in this thread.

Please, moderators, if you think opposite fell free to edit this message.

Best Regards,

jofunk

Thanks Jesus for your input. The pages you posted are good reading..... As far as the CG goes it will be moved up to 10 or 12%MAC. I know where that is. The cad drawing for the flat plate glider shows the 29%MAC at the CG circle. Each line forward shows 25, 20 ,15, and 10% MAC. I also have those locations marked on the jet. We'll see.

Hustler58

My Feedback: (1)

This is 25%

mr_matt

My Feedback: (10)

In my experience, these type of planforms have so much fuselage area, especially in front of neutral point that these simple geometric MAC calculation methods don't work well.

I suggest a scale chuck glider, balsa or foam board. The bigger the better

jofunk

I was able to save the pockets and reuse them.


I had to make a new F7


There are a few segments of the skin that survived to line everything back up on.


Vladimir made a delivery the other day. He worked some magic and has the gear back together as good as new, wow!
Thanks 58 for the work........ Yes Mr Matt the chuck glider is coming.....

jofunk

It is amazing what you can find if you take closer look. Vladimir checked out a discarded empty wire spool and it turns out the sides are 19 ply 15/16" plywood.


I don't know what that would cost if you had to buy it.


The plywood made perfect blocks to build up the temporary fixed gear for the next go.


Here they are finished ready to bolt into the plane. The height will be correct but the stance will be wider.

Pavel Pankratov

Holy cow, are you sure that the Russian documentation does not mislead you?
I would not be so sure ...