mongo

My Feedback: (15)

i managed to leave out the word, lower, between of and intake in the last post.
just looking for a way to take advantage of the carbon inlet strength.

tmgreen64

Gary,
I am working on the main gear, are you happy with the compression on the struts? Did they compress when loaded. I am just adding a little reinforcement. my toe in/out seams fine.
Tgreen

Viper1GJ

My Feedback: (20)

Yes the main gear struts seem to be working OK. They looked like they would not compress and make the tires vertical but with weight on mine are doing ok.

Viper1GJ

My Feedback: (20)

Nice day at FIF today before the winds got high.


First flight of the day and landing was good. The fuel system is working perfectly and I am running an 8 min timer with at least 1.5L remaining. I think my CG may be a little too far aft because the jet seemed a little pitchy and wanted to hunt a little in level flight. The brakes were much better than the first two flights yesterday and worked well.


However, we had an accident when taxing back into the pits that broke the vertical fin. After the two flights yesterday with weak brakes (because of my bad set up) we were paying close attention to make sure they were working today. After landing and before entering the shut down area I did a brake check and the jet slowed. I added some thrust to turn off the runway and my close friend and spotter thought the brakes were not working. He lunged toward the tail to stop the jet from entering the shut down area just as I applied brakes to stop and shutdown. The jet stopped and he could not. He tried to avoid falling over the jet by rolling away and he landed on his back. Fortunately he was not hurt and was able to get up ok. Some how during the fall he bent the vertical fin to the left and it broke just below the dorsal. The damage will be easy to repair as it is only skin and plywood that broke. The hardest part will be finding some matching paint colors. So as far as I know I'm the only pilot at First In Flight Jet rally that has wrecked the same jet twice on the ground. They need to make an award for this achievement.


So as sad, funny, tragic, or goofy as this accident was, it showed a design weakness in the vertical tail area that I will fix during repairs. The dorsal base of the vertical fin has carbon fiber on the inside that extends away from the base about 1" into the top of the fuse section. The airex material broke almost in a straight line along the edge of the carbon fiber.



Internally there are two formers that hold the clamps for the carbon posts in the vertical fin. The rear former plywood broke and separated when the fin was hit. The front former does not extend past the edge of the carbon fiber. My view is that since the the carbon fiber and front former do not extend down into the fuse, there is nothing but the rear former and airex material holding the vertical fin on the jet.


The front former only extends a little into the top of the fuse and does not seem to be bonded to the carbon fiber. It seems to be bonded just to the airex material and has very little structural attachment to the fuse.


In my opinion the front post former should extend deeper into the side of the fuse down to where my finger is and be attached to a band of carbon fiber inside the fuse skin.


The rear former does go around the fuse and tie the rear fin post to the fuse structure properly but I would recommend having a band of carbon fiber around the inside of the fuse to spread vertical fin load into the fuse structure.

I am definitely not suggesting we need to build this thing to be tackling dummy but I am concerned that somebody may try a high speed knife edge pass and possibly snap the vertical fin off. So I suggest al little more structural attention to the vertical fin formers and carbon fiber in the surrounding areas.

Viper1GJ

My Feedback: (20)

I want to commend Mario at GLC for outstanding customer service by shipping me a replacement nose gear after the first one fell out and was damaged. Unfortunately it arrived just after the taxi accident happened. I will beef up the nose gear mount and get it installed during the repair process.

mongo

My Feedback: (15)

you are finding all the little things the rest of us need to fix, before we fly.

a
BIG THANK YOU

hang in there.

Viper1GJ

My Feedback: (20)

First In Flight Top Gun Award




It was completely unexpected but I was just presented the FIF Top Gun Award for flying the F-16XL and working to get it flying again after the nose gear failure. I don't know how they make these choices but it was truly an honor. There were many people who said it really looked great and were looking forward to seeing it fly again. Thank you FIF for the honor!

Frank Alvarez

Hello Gary,

Congratulations!
It is quite the unique aircraft. Not to mention what you've been thru to get it airborne.
When the time comes, we'll shall get both delta jets up in two ship.
Frank

jf16crew

All,
I know you see all the things gary has done. But mine is only has a 3rd fuel tank. There are things that need to be done before the next batch comes out but mine is about 30 flights in now and it's solid. I see alot of people getting upset and saying it's unsafe or things have to be fixed without actually seeing the airframe in person is silly. This jet flys amazing and really isn't to bad. Im going to continue to fly mine unmodified. The second one I built is modified but I really don't feel that alot of it is required at all

tmgreen64

I agree, I have some minor thing I am doing to my XL, but it is just the way I like to do things. I am adding some a little Carbon fiber on the gear plates and the where the wing clamps bolt to the bulkhead. I am in the process of making a third composite tank. This is the time of year I like to boat and fish, and I build slow, but by the end of summer I plan to fly the crap out of that bad boy. The airframe is just fine.
T Green

Viper1GJ

My Feedback: (20)

Photos by Jenni Alderman from FIF 2021. Thanks Jenni.


First day take off wreck when nose gear plate came out. You can see the nose gear getting dragged along the pavement inside the main gear well. It looks like the pitot tube and radome saved the nose gear door.


Taxi out the next day with fixed down nose gear. I love the way this jet looks.


F-16XL number 3 for take off.


Lift off


Initial climb attitude


Flying around with the nose leg in a cast!


This is flight 5 after I took the HVAC tape off the nose gear well because it did not stick.


Gear pass


Final turn


Short final


Round out



Flare


Touch down. The jet is very easy to land. Looking forward to flying it again!

mongo

My Feedback: (15)

and i looked through all 2640 pix to see those...

Viper1GJ

My Feedback: (20)

Touch up paint


I had a chance to make the 45 min drive to the big city down the road and stopped by Home Depot to get some touch up paint for the scratches on the F-16 XL. I took and aileron and the canopy and they took scanner shots and mixed up some light grey, dark grey, and blue. Best I can tell it's pretty close. Good enough for my up coming patch ups anyway.

mongo

My Feedback: (15)

yer gona use the behr latex satin

and yeah, i saved the pic with the code info on it..

i need some of the blue.

tmgreen64

Rust-oleum ultra 2X Satin Ink Blue is almost a exact match. and the Poppy red, I am going to repaint the tail with poppy red, got the paint at my local ACE hardware
Tgreen

Viper1GJ

My Feedback: (20)

Thanks for the tip, I'll check it out.
Gary

tmgreen64

OK, I wanted to give it a try, making my own fuel tank. I started with that white laminate shelving wood, and a piece of plastic from an ceiling light. This is my first attempted to see how much material/fiberglass I should use. If I thought that it was going to come out this good, I would taken more time. That orange stuff is the grandkids modeling clay.
My plan is to make two molds, one being a little bigger than the other. It will be uses as a cap. then the first layer will be Kevlar, if I can source a small amount. Looks like it holds about 1.4 liters. I am using west system with 206 hardener. yesterday the humidity was about 100% so I will need to move my operation inside. and that might be a problem with the wife.

Viper1GJ

My Feedback: (20)

I've had several questions about the status of my XL repairs. After I got back from FIF I have not touched any RC projects. Been swamped with home, camper, grandkids, vacation, and etc, etc, stuff. Hope to get back in the shop in a week or two and get started again.
Gary

F900

My Feedback: (2)

I flew mine in the early AM today and just about a perfect as you can get, only able to get one flight in due to an event but the new CG changes, I installed a new Xicoy landing gear controller (which is a must) made the F-16XL a good flying jet.

Going to fly it at a local jet event this weekend and hopefully get some good video.

Viper1GJ

My Feedback: (20)

Congrats!
What was you new CG and how did you fix the brakes?
Gary

F900

My Feedback: (2)

Gary - CG is probably very similar to yours, I have 2 x LiFe 3000 2S rx batteries just slightly before the nose cone and turbine/landing gear battery's just at the very back at of tray below the cockpit. Your tank is installed, powered by a ACEx 190

When I get sometime I will put it on my Xicoy CG meter. On take off its probably slightly nose heavy but as your fuel tank drains and when switches to the 2 main tanks, after 5mins of scale flying I had over 70% remaining in both tanks which puts it right on the CG, I will increase to 6mins flight time and see how it feels, if I end up just slightly aft of the CG for landing for this jet that's OK. It seems to like the higher alpha landings with no issues, just got to keep on the power

As for the brakes I'm just using the AG63 brake/steering gyro and its tied into the Xicoy LGC13C landing controller set at 2amps, the gear is retracting is slower than I would like but the gear retracted fine using a 2S 7.4v Lipo. I would use a 9.9v but I'd hate to stress or burnout the retract motors. From the time your hit the retract switch until the gear doors are closed your looking at 30secs. It's fine, I can live with it as long as it's reliable

2 F-16XLs will be flying tomorrow so I am looking forward to it.

tmgreen64

As for the brakes I'm just using the AG63 brake/steering gyro and its tied into the Xicoy LGC13C landing controller set at 2amps, the gear is retracting is slower than I would like but the gear retracted fine using a 2S 7.4v Lipo. I would use a 9.9v but I'd hate to stress or burnout the retract motors. From the time your hit the retract switch until the gear doors are closed your looking at 30secs. It's fine, I can live with it as long as it's reliable

2 F-16XLs will be flying tomorrow so I am looking forward to it.[/QUOTE]



Do the brakes hold with the JP controller? I was thinking about having my doors operate from the receiver.

Tgreen

Viper1GJ

My Feedback: (20)

Hi Robert, I'm looking forward to seeing pics of that!

I'm going to do the same as you and use the AG63 to get all the 3S volts to the brakes. 2S on the JP brakes at this weight is not cutting it. I will keep the gear retraction on the Xicoy LGC-15 controller set for 8v and I think mine were set at 1.5 amps. My cycle time is about 15 seconds. I don't want to cook the gear motors with 3S voltage and there is no way to get extra voltage to the brakes through the gear controller so I will get the gyro steering and gyro braking from the AG63. Hopefully I'll get back working on mine in a couple of weeks.
Gary

F900

My Feedback: (2)

For the brakes I use the 3S turbine battery, Josh tied it into the AG63, so I didn't have use another battery. So myself and Josh were able to both fly at the same time today.

I'm uploading the video as we speak and I'll provide some context so your not wasting 8mins of your time Should be posted soon.

F900

My Feedback: (2)

See the video below, so just for contact this fly in event was for all types of r/c aircraft and experience levels, it was fairly busy so first 3 mins myself and Josh had to circle around while we wait for someone to get their r/c taildragger on the otherside if the runway.

Just remember I've only had 1 full flight earlier on the same day, I flew it while it was in the air yesterday but never had a take off or landed it until today. Pryor to today's flying it only had 2 flights total (yesterday and 2 months ago when the original landing gear controller failed). Josh has about 20+ flights on his.
In the meantime I have been flying my BVM Rafale ( which has been very helpful) and I can't say enough about how well the Rafale fly's

I don't expect you to watch the whole video (most don't and just watch the take offs and landings) but watch the landing just before the threshold you will see me come off the elevator a little that causes the nose to dip. This is due to when I am flying the BVM Rafale the nose on landing is naturally at a higher AOA so I'm not holding the stick back and I've got so used to it, it takes more than today's flight to get a similar setup, so for the next flights I will add a flight mode for landing.
Overall Josh did a great job with the build and modifications that I wanted and posted in previous posts. Overall I find it very easy to fly and it's very stable, it is a good flying jet.

When I try and compare it to flying the T-1 Eurofighter, CARF J-10 and BVM Rafale it's too early to tell but it does have a place on been a solid flying jet. I don't find it hard to fly, it tracks well and from what I have seen once setup correctly it does not have any bad habits. It's not designed as a 200mph jet, it's more for scale like flying and high AOA flying which it does very well at.

The 1st XL has a ACEx 220 installed and I have a ACEx 190 so you can see the differences. Josh is going to get the same gear controller as me, (his one gave him some trouble today) I had zero issues with the gear today, also you can't really tell that the runway has a I think its 12 degree down slope, so u can see the brakes work well and its not sliding all over the place thanks to the AG63 steering/brake gyro.