Official FlightLine RC 1600mm F7F-3 Tigercat Thread

[Larry D]

Question about the placement of graphics. The graphics sheets all seem to come with two different sizes of the "stars and stripes" for the F7F. Does the larger of the two go on the wing or the fuselage? Thanks in advance for your advice.

[theoldALFER]

WINGS
U R Welcome

[Bob Vincent]

Hi All,
Quick question, since I haven't read this entire forum, my Tigercat on a 3rd flight of the day when I plugged in the battery the controls went crazy! I had ailerons pinned all the way left, one flap all the way down, and no retracts. I thought maybe I have the wrong plane selected on my radio, but nope. I tried several things and thought wow, must have lost the main board that all the wing functions plug into with the ribbon connectors. So I bought the set with new board and both new wing boards. That didn't fix it but the lights were working again. Odd..... So I started testing every component individually. I found 3 failed flap servos, and all 3 retracts dead. I have no clue what could have happened unless a retract failed and caused over current in those systems and burned up the 3 digital servos and all retracts. So now I have to buy 3 servos and new retracts, but they are out of the mains. It's truly not the cost so much that bothers me at about $80 for all of it but the fact of what happened? I am SO glad it didn't happen in the air!. Anyone else have issues like this? I have since tested the ports on the wing boards with other servos and the circuits are indeed good and functional. Weird to lose 6 components all at the same time with no explanation? Obviously something shorted and caused this.

Any ideas?

[nuts-n-volts]

Check the voltage at the bec. Motion says that anything over 5V can be bad for their systems. The retracts especially are prone to failure over 5V.

[Bob Vincent]

Check the voltage at the bec. Motion says that anything over 5V can be bad for their systems. The retracts especially are prone to failure over 5V.

Copy, tested BEC and is the stock one and shows 5.1v. What ever happened was sudden and all at once. Just bums me out that I have to spend $90 for a ghost I can't identify unless it was a servo or retract failure that caused all of it.

[Pauly]

Some of you guys were in discussion about using takeoff flaps or landing flaps. I have rarely used mine in both takeoff and landing. The Tigercat flys so well you really don't need them. I'm not saying I haven't used them, but this is one sweet bird and a favorite.

[Bob Vincent]

I will use flaps on windy or cross wind days. It slows way down and use power to control pitch. lands on the mains every time that way. Of course it pretty much lands on the mains anyway LOL! Yeah one of my favorites too

[Larry D]

Nose gear steering problem. Any constructive ideas would be appreciated. About a month ago my Tigercat had a really hard landing and the nose gear pin sheared on the retract. I replaced the entire retract which was pretty easy. Made sure the steering arm was ok (it was), realigned the pushrod which was not bent. Thought everything would be fine. I took it to the field for a flight and on taxi out she was steering HARD left with the stick centered. Mmmm. Rechecked everything on the bench and everything appeared fine. Rechecked the servo with a servo tester to ensure it was centered and it was. Taxied again. AGAIN hard left with very little ability to turn right. I canted the nose gear slightly to the right and got a little ability to steer right. VERY little. So, I thought maybe the servo stripped and it just wasn't showing up, so I replaced the servo. No luck, so I did a complete stock replacement of the retract + nose gear + steering arm + push rod. Got back to the field, taxied out, same problem, on throttle up, hard left with the stick is centered, I countered with heavy right rudder just to stay reasonably straight and of course when it lifted off it immediately went right as I expected. Decent recovery but NASTY takeoff. A friend at the field had a tach, so we checked the RPMs on each prop and they were within 100 RPMs of each other. What am I missing? Communicated with MRC and a half dozen highly experienced pilots at my field and while the suggestions were helpful (I tried all of them) most were "don't have a clue". Even sat down with a highly experienced kit builder and we checked all of the setup boxes. Takeoffs are simply not safe and I have no desire to crash this big beautiful bird again. Thoughts? Suggestions? Do this? Anything? Thanks in advance.

[Tigercat]

Sound like you have a main gear locking up. Check to make sure both mains spin freely

[Larry D]

I wish it was a main hanging up, but they are both free and clear with no drag on either :(, but thank you for the suggestion/recommendation of something to check Tigercat.

If anyone is familiar with the fuselage controller module (FCM), it seems that this module may be limiting the throw on the steering servo. When I use a servo checker, I can get full deflection left and right but when I connect it back to the controller module it seems to limit the deflection to < than 50%. I think the only thing I have not replaced to try to correct this nose gear steering problem is this controller module, but I don't know anything about the electronics/programming (if there are any) in the FCM and can't find much information on it to try to determine if this module needs to be replaced too. Apparently the FCM connects the nose steering servo with the rudder servo on the same channel with no ability to independently trim. Hate to just keep replacing things that turn out not to be the cause of this problem, but what the heck....it's only 10 bucks.

[Mad Baron]

Have you checked your end point adjustment on you transmitter? That is one idea I came up with since you have full throw with a servo tester.

[Larry D]

Have you checked your end point adjustment on you transmitter? That is one idea I came up with since you have full throw with a servo tester.

I have not adjusted the end points at all...Mmmm, good idea! Thanks. I did check based on your suggestion and my end points for the rudder are 100%/100%. and since the rudder servo and the nose gear steering servo are apparently tied together through the fuselage controller module, wouldn't setting end points (in my case channel 4) also set the end points for the rudder? If replacing the FCM (it is on order) doesn't solve the issue, I will try adjusting the end points and see what happens. Thanks again!

[AllThumbs]

...

[AllThumbs]

I have not adjusted the end points at all...Mmmm, good idea! Thanks. I did check based on your suggestion and my end points for the rudder are 100%/100%. and since the rudder servo and the nose gear steering servo are apparently tied together through the fuselage controller module, wouldn't setting end points (in my case channel 4) also set the end points for the rudder? If replacing the FCM (it is on order) doesn't solve the issue, I will try adjusting the end points and see what happens. Thanks again!

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One more thing you might check...

I'm assuming when the airplane is static with the rudder stick centered, the nosewheel is properly aiming forward, and moves freely the correct direction when you steer. That being the case, and noting the other things you checked, I would next look at the alignment of the main gear. They should at least be aligned parallel with the centerline, or better yet, toe'd inboard slightly. I had a friend with a A-10 that would skid left and right like it was on ice when taking off. I made the same suggestion to him, and sure enough, the main gear were slightly toe'd outward. This makes steering unstable, while inward toe makes steering more stable. It's the same case whether the airplane is a tail-dragger or nose-steered. Having a nose-steering airplane can sometimes hide the misalignment of the mains, and make it less noticeable.

I noted in an earlier post that the two screws that slide in the shock absorbing gear can come loose and allow the wheel to wiggle. If you have the shock absorbers, that might be something to check. You might also check that the main gear servo mount is still solid in the foam.

[Larry D]

Great suggestion Thumbs. I worked a bit on the Cat yesterday and rechecked all of the nose gear setup. On static the nose gear has been and continues to be free and correct. I have not checked the main gear alignment. I will double check that. I do have the "shocks" installed. Something may have slipped and come to think about it, those are probably the only grub screws that don't have Loctite (blue), On my tail draggers the mains are all slightly toed in and find that they do seem to track much better. Really good suggestion! I'll do that and report back. Thanks.

[Larry D]

Reporting back on nose gear steering issue. I was able to get to our field today and test the Cat nose gear steering issue. Thanks to Thumbs and everyone for your kind and most helpful suggestions. I replaced the FCM and re-aligned everything (again) this time paying close attention to "toe-in" on the mains. I toe'd in both mains slightly (give or take 2 degrees) and I am happy to report take off rolls were MUCH better. Not perfect, but it at least allowed me to safely get her in the air for three flights today. I love how this plane flies when she is trimmed. Guys - I can't thank you enough for all your constructive comments, recommendations and suggestions. I learned some valuable lessons. I will keep working on it to make it even better. I have an Assan AG61 nose gear steering gyro on order to perhaps help even more and when it arrives and is installed, I will do some tests with that too. It's SUPPOSED to help keep the nose on the centerline without stick input. We'll see.

[AllThumbs]

Congrats, Larry! I had a couple of other thoughts on the subject as well: Remember that there must be sufficient weight on the nosewheel for effective steering. I've come across models before that had that problem, even with the C.G. in the recommended position. You might push your battery a little further forward (within the recommended CG range) and see if that makes the steering more solid. That would make for a more stable flight, and would cause you to need a little more up elevator to rotate at takeoff, depending on how much you move the CG forward. If the airplane tracks stable at low speed taxi, but is still a little squirrely on the steering on takeoff roll, that might be something to check. Sounds like you've got a manageable situation now, though, but I thought I might throw this is to complete my thoughts on the subject... Happy flying!

Post-script: If you find that the steering gyro doesn't help, that could be an indication of not enough weight on the nose gear. The wheel can't steer if it's not planted solidly on the ground!

[Larry D]

The Assan AG61 nose gear steering gyro finally arrived and I got it installed and setup on the Cat. I learned some more lessons on that, but if anyone is interested, I am happy to report that it works perfectly. Take offs and landings are perfectly straight (and safe). Of course this assumes that you have the nose pointed straight down the runway. Even ground steering has improved dramatically. Very happy with this little addition. It was a bit of a chore to figure out where and how to mount it because the leads on the AG61 are so short. Now I can say I am so happy to have this beautiful bird back in the air safely and when landing - piece of cake!!! Super straight rollout every time. So far :)

[Denniswpb]

Just curious if the Admiral 6ch receiver with stabilization would not have done that also with the rudder gain turned up.. I'm interested in seeing a picture and a brief installation summary.

[Denniswpb]

Copy, tested BEC and is the stock one and shows 5.1v. What ever happened was sudden and all at once. Just bums me out that I have to spend $90 for a ghost I can't identify unless it was a servo or retract failure that caused all of it.

I have a Flightline Corsair that had a similar issue, but worse. I came in for a landing then went to take off again. It made a weird noise on takeoff roll so I shut her down and as I turned to taxi back to the pits, smoke billowed out. I ran over to it and yanked off the battery hatch and saw orange flames under the battery shooting up!! Thankfully a fellow club member ran out with a fire extinguisher and put it out. What happen was the ESC crapped out and caught fire. Well that would have been fine, but it shot 22v to ALL the electronic components and fried them. Yep, every servo, the receiver, blue box controller, wing connector boards, everything except the motor. $200+ later, it's back in the air but still smells like smoke. My point in all that was that the ESC is probably the culprit and don't trust it! I've heard from a few people that the ESC's that Flightline installs have had issues like mine did. Sure hate to see you put new electronics in and have the ESC burn them out again.