Solved What plane next?

[Vimana89]

Do I need plans or should I just take hints from other planes and youribe clips and make my own plan?

If you've got the itch to custom design, then go for it by all means. Fair warning, it is a bit more involved than making a design from a kit or plans where everything like the CG and wing loading and dimensions of the various components of your air frame and control surfaces are all thought out for you. At least you know how to fly a trainer...that's more knowledge than I had when I first started the hobby, already wanting to do custom stuff.

Make sure the things you are taking from different planes as inspiration fit and flow together, and you are not just "Frankensteining" blindly, for example, to make a tailed delta, I couldn't simply short couple a tail plane to a delta wing and bam it works. The air flow was causing bad stalls, and I had to make sure there was some length in between the main wing and tail plane on the next version, and added winglets and twin tails to reduce air flow turbulence at key points. This ended up solving the problem. Share your ideas and build processes here so we can help along the way!

 

[Merv]

Wow. I thought the would be around 150 dollars.

I cut my own planes from foam board and use cheap components from eBay, Banggood and Hobby King. Shipping is slow, 3-4 week and service is minimal. The reliability of the stuff is similar to all of my buddies that use name brand components. In my humble opinion, those who pay more for the name brands are not getting any better quality but they are getting much better service and convince. If I bought name brand components the all up cost would likely be $150. You would still be able to move those components to a new plane.

If I had a local hobby shop, I would support it. My nearest shop is 90 minutes away and one with more stuff than I have in my basement is 3 hours away. For me mail order is my only choice. For me, the cost savings are worth the wait.

 

[Merv]

So would it be a viable option to mod my Apprentice S into something faster with better

I'm guessing your Apprentice will do more than you know. If you want to get more out of it, I would suggest moving the CG aft and increasing the throws on all control surfaces. You'll need to do this is in steps, start by increasing the throws a little at a time. When you have the rates on the Tx turned all the way up, you will need to start on the control linkages. To increase throws move the control rod on the servo outwards and/or the control rod on the surface inwards. Do this one or two holes at a time. Be sure to test if the servo is binding, that is the servo want to move more but can't. You will hear the servo begin to strain. Set the end point on the Tx to prevent servo binding. At each new level be sure to do a stall test. Get the plane high, cut the throttle and slowly add up elevator until you are full up. When the wings stall, the plane will drop out of the sky. To recover, let go of the sticks, the nose will drop, the plane will pick up speed, add some power and clime out. If you discover this as you are landing, 10 feet off the ground, you will crash the plane, at 200 feet high it's kind of fun. After you have the throws maxed, start moving the CG aft 1/4 inch at a time. Be sure to repeat the stall test at each new CG, the stall will change.

The stock Apprentice is a very stable plane, by turning up the throws and moving the CG aft, you are introducing instability. How much instability you want is a matter of personal choice. If you get too much, just back it off. Play with it until the plane flies the way you want it to.

When I maiden any new build, even if is a plane I have flown for years, I start with low throws and a CG @ 25%. When I get the plane trimmed out, I'll turn up the throws and move the CG aft until it flies the way I want it to, usually around 30%.

 

[OlliePackman]

If you've got the itch to custom design, then go for it by all means. Fair warning, it is a bit more involved than making a design from a kit or plans where everything like the CG and wing loading and dimensions of the various components of your air frame and control surfaces are all thought out for you. At least you know how to fly a trainer...that's more knowledge than I had when I first started the hobby, already wanting to do custom stuff.

Make sure the things you are taking from different planes as inspiration fit and flow together, and you are not just "Frankensteining" blindly, for example, to make a tailed delta, I couldn't simply short couple a tail plane to a delta wing and bam it works. The air flow was causing bad stalls, and I had to make sure there was some length in between the main wing and tail plane on the next version, and added winglets and twin tails to reduce air flow turbulence at key points. This ended up solving the problem. Share your ideas and build processes here so we can help along the way!

I have a fair amount of knowledge on free styling like this because that's what I first wanted to do when I got into the hobby before I decided it was too hard. I will probably base it of

I'm guessing your Apprentice will do more than you know. If you want to get more out of it, I would suggest moving the CG aft and increasing the throws on all control surfaces. You'll need to do this is in steps, start by increasing the throws a little at a time. When you have the rates on the Tx turned all the way up, you will need to start on the control linkages. To increase throws move the control rod on the servo outwards and/or the control rod on the surface inwards. Do this one or two holes at a time. Be sure to test if the servo is binding, that is the servo want to move more but can't. You will hear the servo begin to strain. Set the end point on the Tx to prevent servo binding. At each new level be sure to do a stall test. Get the plane high, cut the throttle and slowly add up elevator until you are full up. When the wings stall, the plane will drop out of the sky. To recover, let go of the sticks, the nose will drop, the plane will pick up speed, add some power and clime out. If you discover this as you are landing, 10 feet off the ground, you will crash the plane, at 200 feet high it's kind of fun. After you have the throws maxed, start moving the CG aft 1/4 inch at a time. Be sure to repeat the stall test at each new CG, the stall will change.

The stock Apprentice is a very stable plane, by turning up the throws and moving the CG aft, you are introducing instability. How much instability you want is a matter of personal choice. If you get too much, just back it off. Play with it until the plane flies the way you want it to.

When I maiden any new build, even if is a plane I have flown for years, I start with low throws and a CG @ 25%. When I get the plane trimmed out, I'll turn up the throws and move the CG aft until it flies the way I want it to, usually around 30%.

I have stalled before on the Apprentice and it's fairly easy to recover so I guess moving the CG would be a good way of introducing instability. If I fettled with the throws on the control surfaces, would this make it out of trim?

 

[Merv]

I have stalled before on the Apprentice and it's fairly easy to recover so I guess moving the CG would be a good way of introducing instability. If I fettled with the throws on the control surfaces, would this make it out of trim?

It's possible there may be a slight trim change, usually not more than a few clicks

 

[OlliePackman]

It's possible there may be a slight trim change, usually not more than a few clicks

I'll give it a go.