Freewing 80mm F-5E Tiger II

[John Bergsmith]

Hey fellas, I'm shopping for a new plane and I think I'm down to the HP F5 vs the T33.

Currently flying an eflite F16 but it seems a little underpowered to me, other than that I really like it and can fly it very comfortably.

Reading on here, I'm gathering that people like it, perhaps a little tricky and the gear can be an issue.

Any other advice or input either way is helpful. Thanks!

I have a lot of flights on my HP version F-5, it’s a hot rod to fly. No bad habits that I’ve found so far. Flaps are very effective, and the jet remains very controllable when they are fully deployed. I’ve had zero issues with the landing gear so far. I fly mine just about every weekend.

The only issue I had to address is the nose section is extremely flexible. I added some flat pieces of carbon on each side to help support the structure better. Easy fix.

I also have the T-33 and it’s a great flyer as well.

[blackonblack]

Hey fellas, I'm shopping for a new plane and I think I'm down to the HP F5 vs the T33.

Currently flying an eflite F16 but it seems a little underpowered to me, other than that I really like it and can fly it very comfortably.

Reading on here, I'm gathering that people like it, perhaps a little tricky and the gear can be an issue.

Any other advice or input either way is helpful. Thanks!

[flyinhigh042]

I took apart a couple of my Mirage nose gears for inspection Flyinghigh. While I cleaned them both up of any sand, dirt and gunk in the mechanism, I don't think it made much difference. I lubed them up good with some dry lube as to not attract more dirt and sand and they both work, but I don't have any faith and confidence they'll not stall.

The only issue I can see is there are a couple of rough threads on the jack screw mechanism on mine. It's very slight, but it's there. It's possible this is causing enough friction to stall out the gear while trying to close.

I don't feel like replacing the current retract to test them, but if I have to swap it out, I may give it a shot to see if a very thorough cleaning and full disassembly did the trick.

Thanks again for the info. From what I’m seeing these particular retracts are almost lacking in power. I suppose it wouldn’t take much at all to cause enough friction as you mentioned to cause it so stall out. The nose gear in particular has a number of things working against it. Including the obvious spring door closing mechanism and having to retract forward into on oncoming airflow. Mine will still work retracting inverted, but I don’t enjoy having to do that. I also applied dry lube to the jack screw with no change in operation. I’m overdue in replacing the retract with the new one I already have.

[Mizer67]

Thanks for the info. I’ll prob just go ahead and replace the retract. I have one in hand and ready to go.

I took apart a couple of my Mirage nose gears for inspection Flyinghigh. While I cleaned them both up of any sand, dirt and gunk in the mechanism, I don't think it made much difference. I lubed them up good with some dry lube as to not attract more dirt and sand and they both work, but I don't have any faith and confidence they'll not stall.

The only issue I can see is there are a couple of rough threads on the jack screw mechanism on mine. It's very slight, but it's there. It's possible this is causing enough friction to stall out the gear while trying to close.

I don't feel like replacing the current retract to test them, but if I have to swap it out, I may give it a shot to see if a very thorough cleaning and full disassembly did the trick.

[flyinhigh042]

I've had the same issue repeatedly on my Mirage, which uses the same retract and spring to close the gear door.

I don't believe it's voltage related. I fly off sandy, clumpy grass and believe it is either "gunk" related (slowing/binding of the worm gear) or just damage related, as the gear stalls out at any resistance. Rolling inverted works sometimes for a short while, given the gravity assist, but the only long term fix I've found is a new retract.

Thanks for the info. I’ll prob just go ahead and replace the retract. I have one in hand and ready to go.

[Mizer67]

Thanks for the reply. The retract operates without issue during ground testing. I did check BEC voltage, it showed 5.2v. I’m using a Castle Creations BEC so I upped the input voltage to 5.4v which for some reason showed 5.3v on the meter. (Tapped into the receiver) After doing this I had three consecutive flights without any issues, so I figured it was fixed. However subsequent flights have once again had issues with the nose gear not fully retracting. On a couple of the flights I had to roll the jet inverted in order to fully retract the nose gear. I’ve since ordered a new retract. When I have time I will install it and see if the issue persists.

I've had the same issue repeatedly on my Mirage, which uses the same retract and spring to close the gear door.

I don't believe it's voltage related. I fly off sandy, clumpy grass and believe it is either "gunk" related (slowing/binding of the worm gear) or just damage related, as the gear stalls out at any resistance. Rolling inverted works sometimes for a short while, given the gravity assist, but the only long term fix I've found is a new retract.

[flyinhigh042]

Are you using a separate RX battery or tapping off of the main battery? If tapping off of the main battery have you checked your BEC voltage under load? When having a retract issue tried reducing throttle to drop the load and then retract? Just a thought. But, could just be a weak retract as well.

I’m just tapping off the main battery. Good idea checking BEC voltage under load and varying the throttle setting. I’ll give that a go before swapping out the retract. Thanks.

[Mwhite1911]

Update:

Much better characteristics with 4000 6s instead of 5000 6s.

Used a Gyro and made the plane a little more rock solid.

Full flaps base to final with less than half throttle, plane still mushy and wanted to pitch up and drift.

Full flaps added when already on final, much better.

Ultimately will fly with 4000 6s. Gyro, and use half flaps / takeoff flaps for landing.

[Bogietrim]

Thanks for the reply. The retract operates without issue during ground testing. I did check BEC voltage, it showed 5.2v. I’m using a Castle Creations BEC so I upped the input voltage to 5.4v which for some reason showed 5.3v on the meter. (Tapped into the receiver) After doing this I had three consecutive flights without any issues, so I figured it was fixed. However subsequent flights have once again had issues with the nose gear not fully retracting. On a couple of the flights I had to roll the jet inverted in order to fully retract the nose gear. I’ve since ordered a new retract. When I have time I will install it and see if the issue persists.

Are you using a separate RX battery or tapping off of the main battery? If tapping off of the main battery have you checked your BEC voltage under load? When having a retract issue tried reducing throttle to drop the load and then retract? Just a thought. But, could just be a weak retract as well.

[flyinhigh042]

Possibly a low voltage situation? Have you tried putting it on a servo tester with a fully charged battery? If it works as advertised there I would check the voltage from the BEC.

Thanks for the reply. The retract operates without issue during ground testing. I did check BEC voltage, it showed 5.2v. I’m using a Castle Creations BEC so I upped the input voltage to 5.4v which for some reason showed 5.3v on the meter. (Tapped into the receiver) After doing this I had three consecutive flights without any issues, so I figured it was fixed. However subsequent flights have once again had issues with the nose gear not fully retracting. On a couple of the flights I had to roll the jet inverted in order to fully retract the nose gear. I’ve since ordered a new retract. When I have time I will install it and see if the issue persists.

[Mwhite1911]

May I suggest increasing your throw on your ailerons as well, this may remove any mushiness you feel. The F-5 doesn't really roll like a drill bit like the Mirage 2000 and the A-4, so it can stand more throw.

Thanks. Yeah I’ve increased the throw on all my planes. I don’t add expo or Dual Rates. Maybe I’ll turn on the gyro and that might counteract the pitch up when I cut the throttle.
It’s a great plane, don’t want to lose it off something silly. I’ll keep testing it out. Appreciate the feedback.

[Phantom]

Thanks. You make some very great points. And it may very well be that I am in a turn with minimal throttle trying to maintain altitude in the turn and the outside wing is stalling causing the nose to drift towards the outside wing.

But as I mentioned, above 50% throttle, great plane for me. Predictable. No bad tendencies.

I’ll see how it works in a descending turn. And I’ll try the 4000 6s as well. Maybe a lighter battery would result in the need for less speed and less of me trying to nose up to maintain level flight in a turn with less throttle.

The way the nose would drift and the ailerons get mushy almost seemed like I had receiver loss. Only thing that got me out of it was adding power.

ill try to test it out tomorrow morning. 👀

May I suggest increasing your throw on your ailerons as well, this may remove any mushiness you feel. The F-5 doesn't really roll like a drill bit like the Mirage 2000 and the A-4, so it can stand more throw.

[Mwhite1911]

Thanks. You make some very great points. And it may very well be that I am in a turn with minimal throttle trying to maintain altitude in the turn and the outside wing is stalling causing the nose to drift towards the outside wing.

But as I mentioned, above 50% throttle, great plane for me. Predictable. No bad tendencies.

I’ll see how it works in a descending turn. And I’ll try the 4000 6s as well. Maybe a lighter battery would result in the need for less speed and less of me trying to nose up to maintain level flight in a turn with less throttle.

The way the nose would drift and the ailerons get mushy almost seemed like I had receiver loss. Only thing that got me out of it was adding power.

ill try to test it out tomorrow morning. 👀

[Phantom]

I’ve flown the F5 a few times and with the CG Spot on (using the front of the plastic cover that hides the wires) the plane takes off great, flies level, but when throttle goes below 30-40% In a Turn, with a clean configuration, the nose rises and the plane gets VERY mushy. Almost to the point of a stall. Adding power corrects it. But it’s almost like the ailerons become ineffective. And when I add flaps I have to keep the power well into the 70% range when turning base and base to final or it’ll nose up and drift. Almost as if the CG is aft, but it’s balanced perfect. I’m going to try to read thru some of these posts to see if anyone has had similar issues.

The problem is that keeping the power up while trying to land means a long final and/or a HOT approach. Not ideal.

Using 6s 5000
Thinking about trying 6s 4000.

High performance model with inrunner

Thoughts?

That is a mystery...how much flap deflection do you use on final? I ask because I routinely use 80° and it always gives me a nose down attitude on final. I don't have the inrunner version, but this is one of the few planes that I use the stock CG with. Usually I move the CG back from manufacturers specs, but I'm using the same CG you are. I fly her with 4000mah all the way up to 8400mah and no issues like what you describe have ever manifested themselves.

One thing that may explain your faster landing approach would be if you have up elevator programmed to mixed with your landing flaps, is this the case? I've never found a need to mix any elevator with my take off or landing flaps with this plane.

Wouldn't explain why it happens in a turn, but I do have a theory about that also. It maybe depending upon your bank angle in a turn that with 30 to 40% throttle you don't have enough speed and are approaching a wing tip stall.

The first thing to happen in a lot of jets is a pitch up when a wingtip stall is imminent. Say you were in a left bank with insufficient speed, while maintaining altitude with elevator. If you wing tip stalled her, she'd pitch up and right, opposite of the turn. The outside wing would stall first, the resultant lift vector as that wing stalls increases lift as that wing drops and the aircraft levels itself, exacerbating the reduction in speed before completley flipping over.

Sounds to me like you've saved your plane from this multiple times. Flying with a 5000mah in a banking turn, with only 30 to 40% throttle in an F-5 with it's short wings,...i would only do that in a descending turn, not one where I was trying to maintain altitude, thats asking for a high speed stall IMHO.

If this theory is correct, 2 things has saved your plane, the over exaggerated camber Freewing built into the wing, and the stability of the F-5's design which good ol Chuck Yeager has raved about many times.

By the way, this is one of my slowest landing jets even with 8400mah on board, but I don't land her like most here. I land her in a conventional nose/pitch down attitude during the entire approach, almost power off. You can find my landing technique in this thread, if not let me know I'll find and direct you to it.

Most folks I see landing her on YouTube are landing her like an F-16 or a delta wing with a high alpha attitude and 40% or greater throttle, with minimal flap deflection. That's why she's landing like a bat out of hell. Folks make this same mistake landing their F-104's in this manner.

[Mwhite1911]

I’ve flown the F5 a few times and with the CG Spot on (using the front of the plastic cover that hides the wires) the plane takes off great, flies level, but when throttle goes below 30-40% In a Turn, with a clean configuration, the nose rises and the plane gets VERY mushy. Almost to the point of a stall. Adding power corrects it. But it’s almost like the ailerons become ineffective. And when I add flaps I have to keep the power well into the 70% range when turning base and base to final or it’ll nose up and drift. Almost as if the CG is aft, but it’s balanced perfect. I’m going to try to read thru some of these posts to see if anyone has had similar issues.

The problem is that keeping the power up while trying to land means a long final and/or a HOT approach. Not ideal.

Using 6s 5000
Thinking about trying 6s 4000.

High performance model with inrunner

Thoughts?

[Bogietrim]

Question. Has anyone here had any issues with the nose landing gear not fully retracting in flight? I just flew off flights #7-10 tonight. On the second flight I noticed the nose landing gear to be hanging partially out and had to cycle the landing gear a second time to get it to fully retract. The third flight went off without any issues. On the forth flight however the problem returned and it took multiple cycles of the landing gear to get the nose to fully retract.

After returning home and putting the jet on the bench I noted the nose retract has just enough power to retract and close the gear door. If I add even the slightest amount of resistance it will stall out. Maybe the retract itself is weak?
Thanks!

Possibly a low voltage situation? Have you tried putting it on a servo tester with a fully charged battery? If it works as advertised there I would check the voltage from the BEC.

[Radar-Guy]

Ordered one (HP) as well. I'm not happy with the paint, it starts to flake off already on the work bench. Plus crooked/misplaced decals and a missing clip to secure an aileron control rod. 😡

I've modelled a nose gear brace and a receiver tray. Both are available for download on Thingiverse.

https://www.thingiverse.com/thing:4488647

https://www.thingiverse.com/thing:4488640

[John Bergsmith]

Question. Has anyone here had any issues with the nose landing gear not fully retracting in flight? I just flew off flights #7-10 tonight. On the second flight I noticed the nose landing gear to be hanging partially out and had to cycle the landing gear a second time to get it to fully retract. The third flight went off without any issues. On the forth flight however the problem returned and it took multiple cycles of the landing gear to get the nose to fully retract.

After returning home and putting the jet on the bench I noted the nose retract has just enough power to retract and close the gear door. If I add even the slightest amount of resistance it will stall out. Maybe the retract itself is weak?
Thanks!

I did have that happen once. Like you, I just cycled the gear and it was fine. Since it only happened the one time out of twenty flights I haven't worried about it yet.

[flyinhigh042]

Question. Has anyone here had any issues with the nose landing gear not fully retracting in flight? I just flew off flights #7-10 tonight. On the second flight I noticed the nose landing gear to be hanging partially out and had to cycle the landing gear a second time to get it to fully retract. The third flight went off without any issues. On the forth flight however the problem returned and it took multiple cycles of the landing gear to get the nose to fully retract.

After returning home and putting the jet on the bench I noted the nose retract has just enough power to retract and close the gear door. If I add even the slightest amount of resistance it will stall out. Maybe the retract itself is weak?
Thanks!

[Johnnyrabuse]

My guess is you’re not off by much.

I've got 12 flights in and twelve landings it's still in one piece I don't like heavy planes busts retracts scrapes wings I like to land like a ballerina you know all twinkle toes ....

Every time I load up for bear with say five thousands on a high wing load I pay for it

Guess I'm a fraidy 🐈