Diving Left At Launch

[caffeinated]

Built the master series spitfire - came out pretty good other than a few cosmetic creases here and there. Amazing stuff that foam board. Went to fly today using Power Pack C components for the kit. Radio, Receiver, and Battery, are Spektrum DX8e, AR637T, Gen2 2200 4S Lipo 50C. Motor is spinning CCW as required. Prop installed with 10x4.5 facing out. CG is 2" back from leading edge (had to add just a bit of weight in nose) and balances nicely.

Now it gets ugly, on both attempts to maiden, holding plane in hand (underneath), throttle almost all the way up - like it wants to jump out of my hand. Let go, and 15 feet to a direct nose dive left into the dirt. Now I'm outta props. And ideas. All the controls are working as they should. Gonna order more props, but thought I'd seek some guidance here first. Plane held up pretty well sans the motor mount loosening but a bit a hot glue and that it ready to go again.

thanks

 

[Hoomi]

Sounds like it might be torque roll, that you don't have enough airspeed to counteract with your ailerons. I had that on my Simple Scout the first few times I flew it. I was taking off at high throttle, and it would bank hard left right after lift-off. When I started taking off at a lower throttle setting, my lift-offs became much smoother.

 

[Hondo76251]

The plane is rotating because the prop is exerting more force than the wings and ailerons, a common problem on hand launches. A c pack wont require nearly full throttle to launch, more like half, maybe less.

I launch with the controller in my left hand, thumb on throttle, plane in right hand ready to toss. My theory is that the right stick is useless until the plane has sufficient airspeed for the control surfaces to be effective so no need to worry about having your hand on the right stick on launch. Most likely, any inputs you apply in the first second of flight will only make things worse, you will have time to get your hand on the controls, i promose.
Apply about quarter throttle, give the plane a firm, but controlled, toss. As you toss the plane increase throttle to half or so. Once you have your right hand on the controlls, begin to fly the plane while increasing throttle for climb out if necessary.

 

[caffeinated]

OK ! Thank you very much for the guidance. Makes total sense too. Ya, had transmitter in left, plane in right. Never even got a chance to hold the transmitter with both hands, sadly. When the new props come, I will definitely get the launch airspeed way down. Thanks again.

 

[Merv]

...Ya, had transmitter in left, plane in right.....

For a madden flight, it would be good to have a buddy toss the plane. So you can have both hands on the Tx. Increases your chance of success.

 

[caffeinated]

Maiden #3 attempt will be with a buddy for sure. It was kinda awkward for me to attempt the launch. It was just one of those perfect days - like no to little wind. Ah, live and learn. Next will be better ! Prop replacements just ordered, now the wait.....

 

[FlamingRCAirplanes]

Maiden #3 attempt will be with a buddy for sure. It was kinda awkward for me to attempt the launch. It was just one of those perfect days - like no to little wind. Ah, live and learn. Next will be better ! Prop replacements just ordered, now the wait.....

Keep it up buddy! I know it well 😏 all of the poor battery’s that got sliced when learning how to fly….

 

[PsyBorg]

A glide test playing catch with the airplane with a buddy will also confirm where CG needs to be. Knowing this sooner probably could have saved me a few crashes in my journey

 

[caffeinated]

Keep it up buddy! I know it well 😏 all of the poor battery’s that got sliced when learning how to fly….

KN4IUU, HAM ? AG5IT here. 73

 

[caffeinated]

A glide test playing catch with the airplane with a buddy will also confirm where CG needs to be. Knowing this sooner probably could have saved me a few crashes in my journey

Good plan too. Although I felt confident in the CG based on balance test, I should have done a glide test too as a good pilot would. Added to maiden #3 checklist! Thanks !

 

[FlamingRCAirplanes]

KN4IUU, HAM ? AG5IT here. 73

Yes sir! What bands you operate?

 

[FlamingRCAirplanes]

Never mind! Just checked out your QRZ page.

 

[FlamingRCAirplanes]

I need to update mine. 😒

 

[Tench745]

I'm going to dissent from what Hondo says a little bit here.
I always hand launch with the plane in my left hand and the transmitter hanging from a neck strap with my right hand on the stick. This makes it easy to let go of the transmitter, set throttle, and get my hand right back on the stick. I set the throttle somewhere around cruise, maybe half to 3/4 throttle depending on the plane. I then give the plane a good, solid toss so it's near flying speed as it leaves my hand. Don't just let go! As soon as the plane leaves my hand I have my left hand on the throttle stick and increase the throttle smoothly to a climb setting.
With a good solid toss you should have enough airflow over the control surfaces for them to work, so your right hand can do something if it needs to.

In summary: start with a lower throttle setting to avoid torque roll and increase it as the plane gains flying speed.
Throw the plane, don't just let go, and you'll reach flying speed sooner and in a more controlled manner.

 

[caffeinated]

I'm going to dissent from what Hondo says a little bit here.
I always hand launch with the plane in my left hand and the transmitter hanging from a neck strap with my right hand on the stick. This makes it easy to let go of the transmitter, set throttle, and get my hand right back on the stick. I set the throttle somewhere around cruise, maybe half to 3/4 throttle depending on the plane. I then give the plane a good, solid toss so it's near flying speed as it leaves my hand. Don't just let go! As soon as the plane leaves my hand I have my left hand on the throttle stick and increase the throttle smoothly to a climb setting.
With a good solid toss you should have enough airflow over the control surfaces for them to work, so your right hand can do something if it needs to.

In summary: start with a lower throttle setting to avoid torque roll and increase it as the plane gains flying speed.
Throw the plane, don't just let go, and you'll reach flying speed sooner and in a more controlled manner.[/QUOTE


Thanks, yes, I was just letting go, so a toss certainly should help. I think the buddy route may be the best bet for me for the first few flights until I get the hang of hand launch/radio coordination. So much different than traveling up a runway for takeoff. Hey, its all in the learning and fun we have while doing it. And rebuilding it. Lather, rinse, repeat !

 

[Hondo76251]

@Tench745 yup, also a common method. I've noticed Bixler launch like that a lot.

I was trying to find a good video of a hand launch, i do it all the time you think it'd be easier to find! Best i could find is this:

About the 1:30 mark you can see what i do. (Even though you dont have to worry about torque roll on a counter rotating twin like the cruiser) if you listen to the throttle carefully I don't really get on the power until the plane is flying after ive thrown it.

 

[caffeinated]

@Tench745 yup, also a common method. I've noticed Bixler launch like that a lot.

I was trying to find a good video of a hand launch, i do it all the time you think it'd be easier to find! Best i could find is this:

About the 1:30 mark you can see what i do. (Even though you dont have to worry about torque roll on a counter rotating twin like the cruiser) if you listen to the throttle carefully I don't really get on the power until the plane is flying after ive thrown it.

oh wow, yea I see what you mean on the throttle, I was so much higher than that at launch. definitely bringing that down! Great that you are flying with your boy. He looks to be having fun too!

 

[Hondo76251]

oh wow, yea I see what you mean on the throttle, I was so much higher than that at launch. definitely bringing that down! Great that you are flying with your boy. He looks to be having fun too!

Yeah, you get a feel for it after a few times, eventually it becomes second nature. Some models require more initial throttle. That cruiser is twin c packs so its got plenty of power.

Heres another with the same plane (after some modifications and a healthy payload) where I have a buddy help launch. I give a bit more initial throttle, but still wait till i get flying before I try a full power climb out. (Especially loaded)

 

[The Fopster]

Here’s a one-person launch and a belly landing. I throw underarm with right arm - no idea why, it just feels “right”. Good luck!

 

[caffeinated]

Yeah, you get a feel for it after a few times, eventually it becomes second nature. Some models require more initial throttle. That cruiser is twin c packs so its got plenty of power.

Heres another with the same plane (after some modifications and a healthy payload) where I have a buddy help launch. I give a bit more initial throttle, but still wait till i get flying before I try a full power climb out. (Especially loaded)

Excellent ! Thank you. Great to have lots of examples now that I know what to look for !!