Help! Tiny Trainer Crashes Immediately

[TinyTrainerFail]

Can't get Mighty Mini Tiny Trainer into air. Throttle on 100%, give it a good throw, angled up slightly. Plane plunges to ground immediately. Bought as speed build kit, value bundle (https://store.flitetest.com/ft-mighty-mini-tiny-trainer-mkr2-value-bundle/ ), which included motor, ESC. Motor is the recommended 2200kv; ESC is 25 amp (12 amp minimum is recommended). It's 3 channel -- rudder, elevator and throttle -- and all three work fine fine. Propeller spins counter-clockwise, as it is supposed to. Possible clue: On several launch attempts, propeller and nut that holds on propeller came off immediately, despite nut being tight. Have built and tried both the wings in the kit. Any ideas what I'm doing wrong?

 

[luvmy40]

Did you do an unpowered glide test?

Did you set your rates?

What radio/receiver are you using?

Check your center of gravity and confirm, one more time that you CRAP is right. I.e., elevator and rudder are moving the right direction with stick input. Check your trim for neutral elevator/rudder or maybe just a bit of up on the elevator.

 

[Aslansmonkey]

Check your CRAP, in case you didn't know, means...

C: Control surfaces - Test your controls and make sure everything is secure. Ensure linkages are connected and won’t fall off.

R: Rips and Tairs - Examine the body of your plane closely looking for rips, tears or crinkles.

A: Angles - Look for structural weaknesses. Eg. check the angle of your tail and make sure it’s not crooked.

P: Power - Check all electronic connections and make sure everything works correctly.

Is your prop spinning independently of the motor when it's on. If you hold on to the motor the prop SHOULD NOT MOVE ON IT'S OWN. Sounds obvious, but a prop that can slip is a prop not at full power.

With your plane off, turn on the radio and max the throttle. Then plug the plane in (best to do this with the prop off, btw). The motor should NOT spin up. Instead it should beep funny at you. Move the throttle all the way down. It should beep funny again. When all this beeping is done you will have tuned your ESC to the limits of your throttle. Theoretically the ESC should come this way, but sometimes they don't. Not having full power could be your issue.

But what luvmy40 says holds true too. load it up to fly, make sure it balances where it should, then toss it POWER OFF into some bushes or something else soft. If should glide gently to the ground, not nose dive, not go up. If it doesn't glide, something is off.

A video or extra photos could help. A side view maybe. Kinda looks like you have some down elevator from the photo you posted, but I cannot tell for sure from that angle, so don't quote me on that.

 

[Draftman1]

I would recommend that you find somebody that knows how to fly and show you.

Flitetest planes are awesome but you just can’t throw it in the air and expect it to fly and that you will know how to fly it.

Getting some experienced help with eliminate a lot of frustrations,

Flying is fun, it shouldn’t be a disaster

 

[TinyTrainerFail]

All: Thanks very much for the information. This was my first attempt at building from a kit; I do know how to fly ready-built planes. I will try your very helpful suggestions. Thanks!

 

[TinyTrainerFail]

Also: The Tiny Trainer kit allows you to make the plane into a glider, by building a different nose. I think I will build that and try it as a glider, to see whether it flies. If it doesn't, then I'll know that I didn't build the plane correctly in the first place. Thanks again!

 

[Merv]

...Any ideas what I'm doing wrong?

Make sure you have the propeller on the right way around, the numbers on the prop need to face the direction of travel. If the prop is backwards, you will only get about 40% of the power.

Here are some other things to look at.
https://www.flitetest.com/articles/preflight-checklist-for-rc-airplanes-free-file

 

[Ketchup]

I don't see it mentioned here so I thought I'd toss in my thoughts.
Make sure that your prop is spinning counter clockwise while you're looking at it from the front, not from behind. I've had props and prop nuts fly off when my motor was reversed like that. If the plane is slowing down rapidly as soon as you throw it then I bet it's a reversed motor.
If it isn't that then I'd follow the other recommendations, starting with an unpowered glide test. You don't need to make the glider nose for this, just get it all set up and launch as you normally would, but without power.
Honestly there's so many reasons for why a plane can crash right after launch that we may need more details if it isn't one of the usual issues like reversed controls. A video or detailed description can do a lot to help us help you if you're still stuck after trying the advice on this thread.

 

[Foamforce]

Also: The Tiny Trainer kit allows you to make the plane into a glider, by building a different nose. I think I will build that and try it as a glider, to see whether it flies. If it doesn't, then I'll know that I didn't build the plane correctly in the first place. Thanks again!

It’s not necessary to convert it to a glider for the unpowered test. First of all, check the balance by putting a finger under the center of gravity mark on the bottom side of each wing. You should do this with the battery installed, but not plugged in. It should balance just a touch nose heavy.

If that works, then do the unpowered glide test. Again, with the battery installed, throw it at your couch or into some tall grass or something. It should glide with the nose either level or slightly down. If it goes immediately nose down, then your plane is very nose heavy and you need to move the battery back, toward the tail, to balance it.

If that glides as expected, then you probably have your elevator reversed.

 

[Ketchup]

It’s not necessary to convert it to a glider for the unpowered test. First of all, check the balance by putting a finger under the center of gravity mark on the bottom side of each wing. You should do this with the battery installed, but not plugged in. It should balance just a touch nose heavy.

If that works, then do the unpowered glide test. Again, with the battery installed, throw it at your couch or into some tall grass or something. It should glide with the nose either level or slightly down. If it goes immediately nose down, then your plane is very nose heavy and you need to move the battery back, toward the tail, to balance it.

If that glides as expected, then you probably have your elevator reversed.

While it is a good idea to glide test, I do disagree with your method of glide testing and here's why.
From what I've learned, typical glide tests happen with the battery installed, plugged in, and with all controls working. The only difference is that the motor stays off so that one can rule out thrust angle or other motor issues.
Checking control surface direction and cg can and should be done with the plane on the ground. If you have already set the cg set on a brand new plane and it noses down in a glide test, I'd bet that the control surfaces are pulling it down rather than an incorrect cg point. When you just toss a plane with everything unplugged, there are a lot of reasons for why it may nose down or stall, so I don't think we can really assume that it is a cg problem when the cg has already been checked and there are other factors at play that aren't under control yet.
Now I'd like to finish this my saying that I'm far from a glide testing expert. These are just my thoughts from the experience I've had with building my own planes and how I would troubleshoot problems with them.

 

[Piotrsko]

Close enough. Battery disconected radio off allows your control surfaces to be anywhere with associated results. Radio on, servos are doing their thing being centered and your control surfaces should be correctly positioned for what you zeroed them for.

 

[Mr NCT]

I'm a big fan of glide testing, especially on my own unproven designs. On proven FT designs my experience has been -

get the CG right per the plans
the control surfaces are centered when the sticks are centered
the elevator goes up when you pull back on the stick
the left aileron goes up when you push left (ditto for right) AND/OR the rudder movement matches the stick
the motor is spinning CW looking from the back (CCW from the front)

And it should be flyable (except for the FT LongEZ )

 

[Draftman1]

All: Thanks very much for the information. This was my first attempt at building from a kit; I do know how to fly ready-built planes. I will try your very helpful suggestions. Thanks!

Awesome

 

[Foamforce]

And it should be flyable (except for the FT LongEZ )

This piqued my interested. Is the LongEZ difficult to fly, or does it balance differently than most planes? And why does it have different CG marks for Glider vs Powered?

 

[JDSnavely]

This piqued my interested. Is the LongEZ difficult to fly, or does it balance differently than most planes? And why does it have different CG marks for Glider vs Powered?

I flew my son's as I am slightly more experienced and it was tricky. And that was with stabilization. He could probably fly it today, but that was about 25 planes ago. Perhaps we will revisit sometime.

 

[Mr NCT]

This piqued my interested. Is the LongEZ difficult to fly, or does it balance differently than most planes? And why does it have different CG marks for Glider vs Powered?

The LongEZ is a fun plane but I wouldn't recommend it as one of your first 3 or 4. It's light, fast and small so it's twitchy and can get away from you quickly. No dihedral so it doesn't self level. It will take quite a bit of abuse except for the canard which is usually the first thing to hit. Even building with a BBQ skewer on the leading edge it's prone to breaking.
But..... When you do get it tuned in it's a blast to fly. Did I mention fast? Here's a video of my second one. This is after getting comfortable with - Tiny Trainer, SE5, DR1, Cub, and Explorer and I think there was a Sportster in there, too.