Help! Functional Dive Bomber with FT Mustang! Payload capacity of the FT Mustang?

[berman00]

Hi guys and gals!

I'm looking for someone with experience flying the FT Mustang who could give me a hand with my project. Any help is much appreciated.

For a University project, I want to experiment a bit with an autopilot software called Ardupilot. My idea was to make a functional, automated dive bomber that drops water balloons! It sounds crazy, but the profs liked it, so I guess I'm doing it. I already have plenty of experience with Ardupilot and software development from a previous internship. I also have some experience with RC models. I have flown the Tiny Trainer and a racing drone in the past, so I know my way around building and flying RC planes.

However, I don't want to use my old Tiny Trainer for this, and I wanted to use the opportunity to build a new plane. The obvious choice for a dive bomber is, of course, the Mustang, so I will try to build that. My main concern is that I have no idea how much extra weight the FT Mustang model can carry for the payload. My idea was carrying a 500 gr payload of water balloons, plus the extra hardware to deploy it, which consists of a servo and some 3D printed parts. It would also need to carry a Flight Controller and a GNSS for the autopilot. Do you think it is possible to fit all this to the standard model? If not, do you think it is possible to modify it to carry extra payload by making the wing longer or generally bigger? I don't have a lot of experience with aerodynamics, so I would simply make the wings bigger while kipping the original shape. I have no idea if this would work well. I assume this will increase the drag so the airplane would fly slower, but this is a sacrifice that I'm willing to make. What do you think?

Thank you all for the help.

Fly safe!
Valen

 

[Foamforce]

That’s almost doubling the weight of the plane. I would guess that you could probably make it fly if you flew very fast, but it would be sketchy.

I would go with something bigger. The Storch comes to mind. It’s technically a warbird, if that’s what you’re after, although I don’t know if they ever carried bombs. It would definitely carry 500g nicely though. My first plane was a Storch that was probably 500g overweight, and it flew adequately well after I got the hang of it.

Another idea would be to scale up a Mustang? Here’sa post where somebody did exactly that.

Scaling Swappable Mustang 140%, my first attempt at scaling.....thoughts, suggestions, 2 cents?

I had great success with the Swappable Mustang, good flier, very solid, it could take a hit! I want to scale it up 140% (40 to 56" wingspan). It won't be swappable, I'll add a few formers to the fuselage, 1/8" plywood wing spar, detachable wing. Any other thoughts or recommendations? Warnings...

forum.flitetest.com

 

[berman00]

That’s almost doubling the weight of the plane. I would guess that you could probably make it fly if you flew very fast, but it would be sketchy.

I would go with something bigger. The Storch comes to mind. It’s technically a warbird, if that’s what you’re after, although I don’t know if they ever carried bombs. It would definitely carry 500g nicely though. My first plane was a Storch that was probably 500g overweight, and it flew adequately well after I got the hang of it.

Another idea would be to scale up a Mustang? Here’sa post where somebody did exactly that.

Scaling Swappable Mustang 140%, my first attempt at scaling.....thoughts, suggestions, 2 cents?

I had great success with the Swappable Mustang, good flier, very solid, it could take a hit! I want to scale it up 140% (40 to 56" wingspan). It won't be swappable, I'll add a few formers to the fuselage, 1/8" plywood wing spar, detachable wing. Any other thoughts or recommendations? Warnings...

forum.flitetest.com

True, it probably couldn't carry all that weight. The autopilot need good flight characteristics and a good range of speeds where it can fly safely in order to work. Maybe I can make the payload smaller too.

Those are some great suggestions. I'll look into it. Thanks!

 

[To_many_planes]

Hi guys and gals!

I'm looking for someone with experience flying the FT Mustang who could give me a hand with my project. Any help is much appreciated.

For a University project, I want to experiment a bit with an autopilot software called Ardupilot. My idea was to make a functional, automated dive bomber that drops water balloons! It sounds crazy, but the profs liked it, so I guess I'm doing it. I already have plenty of experience with Ardupilot and software development from a previous internship. I also have some experience with RC models. I have flown the Tiny Trainer and a racing drone in the past, so I know my way around building and flying RC planes.

However, I don't want to use my old Tiny Trainer for this, and I wanted to use the opportunity to build a new plane. The obvious choice for a dive bomber is, of course, the Mustang, so I will try to build that. My main concern is that I have no idea how much extra weight the FT Mustang model can carry for the payload. My idea was carrying a 500 gr payload of water balloons, plus the extra hardware to deploy it, which consists of a servo and some 3D printed parts. It would also need to carry a Flight Controller and a GNSS for the autopilot. Do you think it is possible to fit all this to the standard model? If not, do you think it is possible to modify it to carry extra payload by making the wing longer or generally bigger? I don't have a lot of experience with aerodynamics, so I would simply make the wings bigger while kipping the original shape. I have no idea if this would work well. I assume this will increase the drag so the airplane would fly slower, but this is a sacrifice that I'm willing to make. What do you think?

Thank you all for the help.

Fly safe!
Valen

Go for the guinea pig of you’re looking for payload. It has a cargo door that can be opened and closed and has a massive carrying capacity. If not look at the A-10

 

[dberg97]

The old trusty Scout XL can handle a hefty payload. I added 3d printed bomb releases under the wings and dropped two 8" whistling bombs. The bombs had to be a couple hundred grams of ABS each. I also had other 3d printed decorative features on my Scout that added additional weight, so without them it would be easily capable of carrying 500g worth of water balloons.

I agree the guinea pig would be a good choice too.

 

[Shurik-1960]

The maximum payload is carried by an overhead glider with a very thick wing profile and the most lightweight design. A 2-meter-tall Vizel was lifting a crate of beer (YouTube video).

 

[Mr Man]

I do agree on the Scout XL, but, when I built the FT Mustang I first put a 3s 650mah all the way up in the nose making the plane fly slow, floaty, and just easy to fly. And then I put a 5000Mah 3s in as far back as I could, (yes, I still had good CG) and it flew WAY FASTER, until my bad battery wire connection (sorry) caused a short circuit making the left aileron decide to go full up and stay there. RIP Mustang.

 

[quorneng]

Your heading suggest the plane is to be a dive bomber. Is "dive" bombing a requirement?
Conventional dive bombing is a process to improve the accuracy from a human pilot sitting in the plane. Unless you are using FPV dive bombing would not benefit a ground bases RC pilot. Dive bombing also significantly raises the aerodynamic load on the plane.
As you have decided on the payload weight the first task is to task is to actually design, build and test the mechanism to make sure it works reliably and that it will not have too big an impact the drag of the plane. The bombs and release mechanism will be the key element of this project.

If you really want to carry a payload then you need to design the plane accordingly. You will most likely have to undertake some experimentation to determine what creates the strongest structure, particularly the wing, for a given weight using the materials of your choice. The choice of materials and how they are used will have a big impact on the result.
Just making the same structure bigger using the same foam board does not necessarily increase the structural strength in direct proportion. Twice as big may not be twice as strong but it will likely weigh 4 times as much. It follows the law of diminishing returns.

My suggestion is to create a reliable bomb and release mechanism release and then given its weight decide what plane could carry it effectively. Very few RC planes have either the power or structural integrity to carry a "disposable" payload equal to their minimum flying weight.
I have a foam RC plane that can carry a disposable load of 40% of it minimum flying weight but I certainly wouldn't want to risk dive bombing with it when fully loaded.

 

[Piotrsko]

To add: I suppose you could add a FPV "navigator" to watch when the target is aligned to the flight. Fpv for the pilot is looking the wrong way for accuracy and sustained dive. This also assumes that you need to actually hit the target as opposed to just getting it wet with spray. Might be a teachable fix, but the experimentation is gonna be long and tedious. No mention if the plane has to do this more than once. Helicopter or RPV with a down facing camera, maybe

Can't just cruise over the target, release at the plotted coordinates and expect a bullseye. If it were that easy warefare would be less survivable.

 

[Shurik-1960]

Small rubber balls with water were dropped by this device.Cessna 150 model with a span of 1.4 meters. From 2 sides to 1 servomechanism.

 

[berman00]

I haven't checked the forum in a while. Thanks for all the suggestions

I already have the motors that I want to use from a previous project. Its a T-motor 2213 - 920KV motor from a multicopter and 9,5 inch propeller. It's not as big as I would like, but it's waht I got. I have four of them. I should have mentioned that earlier too.

Given what I read, I think the best option is to change the requirements, since it would be unfeasible to carry the load I originally wanted with the model I want to build. The fact that the power plant is already decided also limits what models I can build. I think the motor is undersized for either the Guinea Pig or the Scout XL. Also, I really want to make a warbird from the second world war, so I think the final model will either be the Mustang or the flite test version of the P-40, which also has a good blueprint and similar size to the Mustang.

I decided to drop a smaller payload, either Nerf darts or some 3D printed bomb like what @dberg97 used with his Scout. Whatever works best. That should also simplify the release mechanism.

Your heading suggest the plane is to be a dive bomber. Is "dive" bombing a requirement?

@quorneng it's only a requirement because I want it to look cool. I don't really care about accuracy that much.

Dive bombing also significantly raises the aerodynamic load on the plane.

That's a good point. Do you think I should take measures to reinforce the airframe? What could be done in this sense?

 

[berman00]

Small rubber balls with water were dropped by this device.Cessna 150 model with a span of 1.4 meters. From 2 sides to 1 servomechanism.

Cool! That will give me some inspiration for the design of the release mechanism. It will probably be mounted on the exterior for simplicity. I have access to a 3D printer so I'll probably end up using that to make it.

 

[M.Peanut]

How about the Stuka from 13th Squadron. It looks great and is an actual dive bomber. https://www.13thsquadron.com/

 

[berman00]

How about the Stuka from 13th Squadron. It looks great and is an actual dive bomber. https://www.13thsquadron.com/

I didn't know about it. That could also be a possibility, thanks.