General Infos needed!

I have that p-40 since this summer but not flown yet, it is from General Hobby, i need to know the Cg location, if you can help me, It has 65.3 '' wingspan and run Os v-95 4 strokes, any specific infos are welcome, thanks.
 

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RandyDSok

Well-Known Member
General Hobby is a reseller and not a manufacturer of hobby equipment. To find specific info you will need to know the exact brand and model of your aircraft. I did browse through their listing of warbirds but didn't see one with the design your picture has... but I could have easily overlooked it since they had so many. If you find out the brand, check if they have a website where you can download the original manual for it.

If you can find a similarly built and size version of the P-40, you could probably use the info from their manual to get you close... I say close since how it is constructed exactly will make some differences. For these types of searchs, I'll use Google and then just go through the listings until I can find what I'm looking for.
 
General Hobby is a reseller and not a manufacturer of hobby equipment. To find specific info you will need to know the exact brand and model of your aircraft. I did browse through their listing of warbirds but didn't see one with the design your picture has... but I could have easily overlooked it since they had so many. If you find out the brand, check if they have a website where you can download the original manual for it.

If you can find a similarly built and size version of the P-40, you could probably use the info from their manual to get you close... I say close since how it is constructed exactly will make some differences. For these types of searchs, I'll use Google and then just go through the listings until I can find what I'm looking for.
I have no informations since it 's no longer available so the reason i'm seeking for some help but all i know is that 's generic brand wich does not help a lot.
 
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RandyDSok

Well-Known Member
Using a similar airplane's info can get you close but it may not be exact do to how the model was engineered. So in reality, it's a complex subject and everything depends on all of the other parts of the airplane... Generically, we'd often say look for the location of where the wing's main spar is located... but did they engineer it to be right at it, slightly to the front or rear of it... or is the main spar even located at or close to the CG is going to always be in question without the original documentation.

Even using formula's and calculations can only go so far... but they are a place to start with you don't have anything else to go by. Here is a page that discusses those Where Should an RC Airplane Center of Gravity be?

In the end, once you have it close... you just go by how it actually flies. A slightly nose heavy plane will fly, some fly better if they balance just a little heavy in the nose, most will fly but will have trouble gaining altitude.

A slightly tail heavy plane will climb at a fast rate, stall, and the nose will drop until it picks up a little speed then climb again only to stall again, they call this porpoising, if a plane is more than slightly tail heavy it will not fly long before crashing.
 
Hey Daniel I did the same as Randy and looked around. Motion RC has warplanes and one looks close Nexa P-40 Warhawk 1570mm (61.8") Wingspan - ARF [NXA1009-001] Motion RC but check out the rest of the site and might help some.

Using a similar airplane's info can get you close but it may not be exact do to how the model was engineered. So in reality, it's a complex subject and everything depends on all of the other parts of the airplane... Generically, we'd often say look for the location of where the wing's main spar is located... but did they engineer it to be right at it, slightly to the front or rear of it... or is the main spar even located at or close to the CG is going to always be in question without the original documentation.

Even using formula's and calculations can only go so far... but they are a place to start with you don't have anything else to go by. Here is a page that discusses those Where Should an RC Airplane Center of Gravity be?

In the end, once you have it close... you just go by how it actually flies. A slightly nose heavy plane will fly, some fly better if they balance just a little heavy in the nose, most will fly but will have trouble gaining altitude.

A slightly tail heavy plane will climb at a fast rate, stall, and the nose will drop until it picks up a little speed then climb again only to stall again, they call this porpoising, if a plane is more than slightly tail heavy it will not fly long before crashing.
So i only hope to be as close as possible of it and being able to fly and land it in one piece, after that i will see if more his needed to be done.
 

RandyDSok

Well-Known Member
OR you can start over and purchase new electronics that way you know what you have.

I believe you misread something there... We were discussing the model's CG ...

I suppose we could have fun with that though ... Not sure how switching out the nitro engine for an electric motor will help with anything but his carbon footprint ... LMAO
 

D.O.G.

Goblin 380 Supporter
I believe you misread something there... We were discussing the model's CG ...

I suppose we could have fun with that though ... Not sure how switching out the nitro engine for an electric motor will help with anything but his carbon footprint ... LMAO
:damnit:I'm sorry my bad . I guess I need to go back to school and learn how to understand the question :sorrow:
 

D.O.G.

Goblin 380 Supporter
It's all in good fun and no foul :chairshot:
But I did find this if it's any help the CG point is around 1/3 of the wing chord and will likely be given in terms of the distance back from the leading edge of the wing, or from the nose of the aircraft.
 
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