FEJ 1/8 F16 Advanced information needed
11-25-2013, 01:38 PM
#1
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FEJ 1/8 F16 Advanced information needed
Guys, I recently purchased a war weary FEJ 1/8 scale F16 advanced that was desperately in need of a make over. I just finished rebuilding the F16, and think it will be a good flyer, however, I have been unable to get information that I need to finish the bird for the maiden flight. I've asked FEJ for the information, but keep getting the same answer to go to a website and download the manual, however the information I need is missing. I did several searches and did find information, but am more confused than ever. I need:
1. The center of gravity with UAT full, gear down, and fuel tanks empty.
2. Control surface throws.
3. Elevator neutral position.
Any help you can provide would be very much appreciated.
Regards, Les
1. The center of gravity with UAT full, gear down, and fuel tanks empty.
2. Control surface throws.
3. Elevator neutral position.
Any help you can provide would be very much appreciated.
Regards, Les
11-25-2013, 04:45 PM
#2
Les,, I am in the exact same boat as you, Picked up a great shape fej 1/8 advanced, same color as yours also. Here is some of the info I have been able to find,, a few PDF files,,if you cant get them to open let me know.
as far as the elevator neutral position, the member I got this plane from was thoughtful enough to mark the elevator neutral on mine,, I have taken some pictures of my elevator assembly.
Also, what turbine is in yours?
as far as the elevator neutral position, the member I got this plane from was thoughtful enough to mark the elevator neutral on mine,, I have taken some pictures of my elevator assembly.
Also, what turbine is in yours?
Last edited by raron455; 11-25-2013 at 05:22 PM.
11-25-2013, 05:42 PM
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Les,
That F-16 is looking good!
This is what I started with:
1. 5.7-6.1 in. If I remember right, 140 mm (~5.5 in) was where I started but found it to be a bit nose heavy for me.
2. Aileron = .6 inches; Elevator = 2.0 inches; Rudder = 1.0 inches
3. I started with the elevator trailing edge even with the fuselage which made the leading edge a bit lower. I believe it was trimmed after the maiden to make the leading edge even lower.
Hope this helps.
Craig
That F-16 is looking good!
This is what I started with:
1. 5.7-6.1 in. If I remember right, 140 mm (~5.5 in) was where I started but found it to be a bit nose heavy for me.
2. Aileron = .6 inches; Elevator = 2.0 inches; Rudder = 1.0 inches
3. I started with the elevator trailing edge even with the fuselage which made the leading edge a bit lower. I believe it was trimmed after the maiden to make the leading edge even lower.
Hope this helps.
Craig
12-01-2013, 09:52 AM
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Craig, sorry to be so late replying, but we went out of town for thanksgiving and didn't return until Sat. Anyway, I appreciate your comments, and have looked at my data, and compared it to yours.
Here is what I found from several threads, and a friend of mine:
1. CG - I found it to be from 140 mm to 175 mm. Either extreme seemed to be out of the ball park, so after much thought and discussion with my modeling buddies here, I set it at 155 mm to start as a good middle of the road compromise. We'll see how it works out.
2. Aileron settings ended up being +/- 20 mm with 25% positive expo. Lower travel rate on lower switch setting
3. Elevator travel +/- 45 mm plus 15% positive expo high rate. Lower rate on lower switch setting. The setting on your plane for neutral seemed a little lower than I expected, but I set mine about halfway between your setting and even with the trailing fuse edge. May not be right, but will try and see.
4. My dry weight came out exactly at 25#. A little heavier than I wanted, but about 2# lighter than when I started. I removed the canopy raising and lowering mech, and also removed dual battery packs and redundant battery feeds.
Always an adventure isn't it. Wish me luck with the maiden. Maybe next week. We had very cold temps and snow here last week, but warmed up slightly next week for a cold front coming through next weekend. If I can sneak a maiden in next week, I'll lucky.
Thanks for the information, and I'll let you know how the maiden goes.
Regards, Les
Here is what I found from several threads, and a friend of mine:
1. CG - I found it to be from 140 mm to 175 mm. Either extreme seemed to be out of the ball park, so after much thought and discussion with my modeling buddies here, I set it at 155 mm to start as a good middle of the road compromise. We'll see how it works out.
2. Aileron settings ended up being +/- 20 mm with 25% positive expo. Lower travel rate on lower switch setting
3. Elevator travel +/- 45 mm plus 15% positive expo high rate. Lower rate on lower switch setting. The setting on your plane for neutral seemed a little lower than I expected, but I set mine about halfway between your setting and even with the trailing fuse edge. May not be right, but will try and see.
4. My dry weight came out exactly at 25#. A little heavier than I wanted, but about 2# lighter than when I started. I removed the canopy raising and lowering mech, and also removed dual battery packs and redundant battery feeds.
Always an adventure isn't it. Wish me luck with the maiden. Maybe next week. We had very cold temps and snow here last week, but warmed up slightly next week for a cold front coming through next weekend. If I can sneak a maiden in next week, I'll lucky.
Thanks for the information, and I'll let you know how the maiden goes.
Regards, Les
12-01-2013, 05:21 PM
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Good luck guys. I've had that exact jet. Mine was also 25 pounds dry. The landing gear in stock form can't take the weight. Especially the nose gear. Grease it every single time or expect true pain and suffering with the nose not locking properly. I'm not trying to be a negative nancy but my happiest day was when I sold her and got something lighter.
12-02-2013, 06:48 AM
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Yeah, I know the feeling......... I probably wouldn't have purchased this one except it had a killer price, and I let my better judgement be over ridden by my impulses. I'll see how it goes; there's always the selling block if I don't like it. I had an origional grey one with the sport gear, and it flew fine, but was hard to see with the camo scheme. This one should be easy to see, but we'll see how everything works out.
Thanks for the information.
Regards, Les
Thanks for the information.
Regards, Les
12-02-2013, 08:54 AM
#7
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I sold raron my F-16. I had issues with the nose gear collapsing but it had nothing to do with the weight. The drag link didnt function correctly so FEJ put a cylinder lock on the down side, which isnt strong enough to hold by iteself. By fixing the drag link, that is itself suffice to hold it. I tested it well and since I did the mod it never once collaposed again. Before I fixed it I had it collapse on taxi a few times. On option is to put some lead weight on the drag link so it fully straightens and stays there.
Also you need a mix on the front gear, so the steering servo will help it rotate in and out when you operate it. This is required.
The weight is an issue but with a rabbit 100 I could stall it out and pull out of it. However you need at least 600 foot of runway to be safe. I have taken off and landed in 300 feet (measured off a real runway) but it was 1 out of 3 times I made it.
I got rid of mine because I only had a 400 foot runway locally and could only fly it at jet rallys.
Keep in mind once gears are deployed you'll need a lot of throttle to keep it up. It if ever flames out, do not drop the gear until close to touch down. If it flames out with gear down suck them up!
THis is true with most scale jets but given the wing loading of this one it makes your chances slimmer of landing dead stick.
Dont be stupid and try to do a high alpha landing. Come in nose down then flare. Yes you can do high alpha controlling decent with throttle and it looks cool but it is extremely risky.
Also you need a mix on the front gear, so the steering servo will help it rotate in and out when you operate it. This is required.
The weight is an issue but with a rabbit 100 I could stall it out and pull out of it. However you need at least 600 foot of runway to be safe. I have taken off and landed in 300 feet (measured off a real runway) but it was 1 out of 3 times I made it.
I got rid of mine because I only had a 400 foot runway locally and could only fly it at jet rallys.
Keep in mind once gears are deployed you'll need a lot of throttle to keep it up. It if ever flames out, do not drop the gear until close to touch down. If it flames out with gear down suck them up!
THis is true with most scale jets but given the wing loading of this one it makes your chances slimmer of landing dead stick.
Dont be stupid and try to do a high alpha landing. Come in nose down then flare. Yes you can do high alpha controlling decent with throttle and it looks cool but it is extremely risky.
12-02-2013, 11:40 AM
#8
The one only thing that should keep you from buying this jet is that its a FEJ product. Did you see how lousy the customer service the OP had?
The manufacture itself didn't know the CG of the airplane. If this isn't the MOST critical aspect of getting an airplane ready to fly, than what is?
As a rule of thumb of setting up jet elevators (or any airplane really, jets are just a little handful more than other types of airplanes) is, when in doubt, just a touch of "up".
Having a jet just jump off the tarmac is a horrible experience. Alternatively, if you have to give it some down input after rotation, that relaxes and lessens your work load through the first few turns. At least, that has been my experience.
The manufacture itself didn't know the CG of the airplane. If this isn't the MOST critical aspect of getting an airplane ready to fly, than what is?
As a rule of thumb of setting up jet elevators (or any airplane really, jets are just a little handful more than other types of airplanes) is, when in doubt, just a touch of "up".
Having a jet just jump off the tarmac is a horrible experience. Alternatively, if you have to give it some down input after rotation, that relaxes and lessens your work load through the first few turns. At least, that has been my experience.
12-02-2013, 03:48 PM
#9
I am fully expecting long landings coming in pretty hot,, I am very lucky that my field is perfect for turbines,, My club field has an 800ft x70 paved runway, we actually have the greater southwest jet rally at my field every year.
As far as the plane,, I have read multiple threads on this particular Plane, and there are opinions all over the board, some positive some negative, the one thing to keep in mind is opinions are are just that Opinions. If everyone liked the same thing, there would only be 1 of any object. I did some research on my jet before I bought it, I am not worried about it coming apart in the air as the new FEJ stuff with the honeycomb seems to, I have the older fiberglass/ply version, Super strong from what I have inspected, however there is a weight penalty for that strength, and I bought mine from a member who had plenty of successful flights on it. I fully expect to have to land the jet under power I dont have any grand illusions of it gliding in like my aerobatic slick. As far as the gear goes, mine seems to lock in place pretty firm, I will find out when I get it ready for flight at full weight. If It gives me any problem out it comes and will be sent out to down and locked, for an electric conversion. I am getting closer to being done with mine, I have done some work to lighten it up, removing the lighting kit and all the wires, running shorter air lines to everything, Etc.
I did finally decide on a turbine, I went with the Jetcat P120sx rated at 30lbs, I am going to dial it back to 25 and see how it goes from there, it weighed the same as the P80, drinks a little more fuel at max, but seems like it will work fine, as there are multiple videos on Youtube of guys flying this jet with that turbine. And the plus side is, If I dont like the jet, I can sell it and the turbine will be more versatile for other frames.
Les, what turbine is in yours?
As far as the plane,, I have read multiple threads on this particular Plane, and there are opinions all over the board, some positive some negative, the one thing to keep in mind is opinions are are just that Opinions. If everyone liked the same thing, there would only be 1 of any object. I did some research on my jet before I bought it, I am not worried about it coming apart in the air as the new FEJ stuff with the honeycomb seems to, I have the older fiberglass/ply version, Super strong from what I have inspected, however there is a weight penalty for that strength, and I bought mine from a member who had plenty of successful flights on it. I fully expect to have to land the jet under power I dont have any grand illusions of it gliding in like my aerobatic slick. As far as the gear goes, mine seems to lock in place pretty firm, I will find out when I get it ready for flight at full weight. If It gives me any problem out it comes and will be sent out to down and locked, for an electric conversion. I am getting closer to being done with mine, I have done some work to lighten it up, removing the lighting kit and all the wires, running shorter air lines to everything, Etc.
I did finally decide on a turbine, I went with the Jetcat P120sx rated at 30lbs, I am going to dial it back to 25 and see how it goes from there, it weighed the same as the P80, drinks a little more fuel at max, but seems like it will work fine, as there are multiple videos on Youtube of guys flying this jet with that turbine. And the plus side is, If I dont like the jet, I can sell it and the turbine will be more versatile for other frames.
Les, what turbine is in yours?
12-03-2013, 05:24 PM
#11
Out of all the 16's I've had my FEJ was the only one I could not do a nose up approach with, it would just slow down too much and if I added a little power it would stop the descent. Mine seemed to like a flat approach, and it would still land slow.
I loved my FEJ 16. I killed it very stupidly. :'(
I loved my FEJ 16. I killed it very stupidly. :'(
12-04-2013, 06:47 AM
#14
My Feedback: (48)
I bought one of the first FEJ F-16's. I'm suprised at some of the weights quoted. Mine's the Standard version and it weighs 20.5# dry with a Merlin 90, which should be 1 - 2# lighter than the Advanced . I picked the Merlin 90 (21.5# thrust) because it was the lightest most fuel efficient engine in its class at the time. Performance is excellent and I've had no problem flying it regularly off of our 380 ft. runway. Landings require about 1/3 throttle. I come in fairly flat and slow, and chop the throttle & flare just before touchdown.
Here's my setup:
Ailerons 25 mm/35% expo
Elevator 50 mm/40% expo
Rudder 25 mm/50% expo
CG 160 mm. The recommended 140 mm. is way too nose heavy. The further back I moved it the better it landed.
Good luck,
Joe
Here's my setup:
Ailerons 25 mm/35% expo
Elevator 50 mm/40% expo
Rudder 25 mm/50% expo
CG 160 mm. The recommended 140 mm. is way too nose heavy. The further back I moved it the better it landed.
Good luck,
Joe
12-04-2013, 09:06 AM
#15
Joe it's well known that the advanced version ends up in hte 25-30 lbs range. In my opinion....the details of the operating canopy and scale gear are not worth it! I would not like to see a flameout on one of these......
Raron......just try to keep it as light as you can. Be prudent with the size of your servos an power requirements = battery size. I think I had a 2200 A123 on mine for rx power, and a 3000 LiFe for ECU. My fwd tank wa a 8oz Sullivan with BVM hardware, and a small UAT.
I did away with the very unnecessary and heavy semi-bypass duct. I also used an EV5 valve and did away with the brake and reract servo, gear an brake valve and gear failsafe (all built into the EV5).
Raron......just try to keep it as light as you can. Be prudent with the size of your servos an power requirements = battery size. I think I had a 2200 A123 on mine for rx power, and a 3000 LiFe for ECU. My fwd tank wa a 8oz Sullivan with BVM hardware, and a small UAT.
I did away with the very unnecessary and heavy semi-bypass duct. I also used an EV5 valve and did away with the brake and reract servo, gear an brake valve and gear failsafe (all built into the EV5).
