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Center of Gravity

Courtesy another poster, but thought I'd share here. "X" marks the spot as they say.

View attachment 4826
Hey Damon, I saw that pic a while back, can't remember where though. Unfortunately all it shows is the centre of the prop shafts in one plane, not COG.
For COG the craft would need to be in flying mode (landing gear up) and a balance point has to be taken not only on the x-y axis but also z axis.
Additionally, the COG will change dependant on payload. Imagine (if it were possible) a Red Epic slung from the belly on the existing mount. The string method would still show COG as the centre of the motors when in reality it would be much lower and also a long way forward.
 
Hey Damon, I saw that pic a while back, can't remember where though. Unfortunately all it shows is the centre of the prop shafts in one plane, not COG.
For COG the craft would need to be in flying mode (landing gear up) and a balance point has to be taken not only on the x-y axis but also z axis.
Additionally, the COG will change dependant on payload. Imagine (if it were possible) a Red Epic slung from the belly on the existing mount. The string method would still show COG as the centre of the motors when in reality it would be much lower and also a long way forward.

Yes, of course. With Z-axis the CG point will be slung low on the Inspire as all weight is beneath the props when landing gear is up.

CG on the fore-aft axis is what I was referring to above, I should have clarified, unloaded, with no camera attached.

The camera moves it forward a touch, more with the X5 than X5 I would think.

Just caring about this as I'm mounting extra batteries.
 
Uhm, that's just a geometrical characteristic. The only relation of the spot you found with the XY position of the COG depends on how the Inspire 1 designers located the 4 motors (probably close enough to your finding with the X3). The Physics textbook's way to find the COG is to hang the object from three different spots. For each position the vertical will pass for the COG so the intersection of the three vertical lines will be right in the COG :).

V.
 
I am wondering the same thing. As in TB47/48's give the inspire relatively bad flight time. I am looking to use aftermarket batteries as well. I have found two options so far:


and


The first option would give more flight time, whereas the second would give redundancy (and a little more flight time). I am not sure which is more legit or if I should even go this route, but I'm pretty sure it's the only way of getting better flight time out of the Inspire. Even if I fly my X5, the weight of both of these options will shift the CG quite far back. Will lead to motor strain/overheating (as the aft motors will be loaded more than the forward ones)? If so, is there any way to prevent this?
 
I am wondering the same thing. As in TB47/48's give the inspire relatively bad flight time. I am looking to use aftermarket batteries as well. I have found two options so far:


and


The first option would give more flight time, whereas the second would give redundancy (and a little more flight time). I am not sure which is more legit or if I should even go this route, but I'm pretty sure it's the only way of getting better flight time out of the Inspire. Even if I fly my X5, the weight of both of these options will shift the CG quite far back. Will lead to motor strain/overheating (as the aft motors will be loaded more than the forward ones)? If so, is there any way to prevent this?
You realize this thread is from 2015?
 
You realize this thread is from 2015?
Yes, I do. It is the only thread that I could find that discusses this topic thoroughly, and as others with similar questions as myself would have more knowledge in this area than me, I decided to see if they had any information that would be beneficial in solving my problem. If you believe it would be more apt for me to create a new thread, I can do so.
 
I am wondering the same thing. As in TB47/48's give the inspire relatively bad flight time. I am looking to use aftermarket batteries as well. I have found two options so far:


and


The first option would give more flight time, whereas the second would give redundancy (and a little more flight time). I am not sure which is more legit or if I should even go this route, but I'm pretty sure it's the only way of getting better flight time out of the Inspire. Even if I fly my X5, the weight of both of these options will shift the CG quite far back. Will lead to motor strain/overheating (as the aft motors will be loaded more than the forward ones)? If so, is there any way to prevent this?

The TB60 Batteries used by the Recce28 mod list for $700. That's basically the price of an I1
 
The TB60 Batteries used by the Recce28 mod list for $700. That's basically the price of an I1

Their company quoted me at $500 dollars (still half the price of the I1) and then said this in an email:

"Please do not follow the Wh on the sticker and ignore that. (I had asked him about the inaccurate labeling of his product). Our price list only denotes the 12000mah.

DISCALIMER: PLEASE NOTE THAT FLYING WITH MOD BATTERIES CARRIES RISK AND YOU ACCEPT THAT WE WILL NOT BE HELD RESPONSIBLE ON HOW YOU USE THE BATTERY TO FLY. WE WILL NOT BE RESPONSIBLE FOR ANY DRONE LOST, DAMAGE OR CRASHES.

We will not comment on the max takeoff weight or any overheating possibility. Fly at your own risk and make your own informed decision."

So a pretty average response for a sketchy company. I'll most likely just buy a couple more TB47's and maybe 3 TB48 (I think for 100-160 Wh 2 spares and 1 in-aircraft are allowed, but not sure if more (less than 100) are allowed after that). The only issue now is that almost every single online store is out of them, so I guess I'll have to wait a while.
 
Their company quoted me at $500 dollars (still half the price of the I1) and then said this in an email:

"Please do not follow the Wh on the sticker and ignore that. (I had asked him about the inaccurate labeling of his product). Our price list only denotes the 12000mah.

DISCALIMER: PLEASE NOTE THAT FLYING WITH MOD BATTERIES CARRIES RISK AND YOU ACCEPT THAT WE WILL NOT BE HELD RESPONSIBLE ON HOW YOU USE THE BATTERY TO FLY. WE WILL NOT BE RESPONSIBLE FOR ANY DRONE LOST, DAMAGE OR CRASHES.

We will not comment on the max takeoff weight or any overheating possibility. Fly at your own risk and make your own informed decision."

So a pretty average response for a sketchy company. I'll most likely just buy a couple more TB47's and maybe 3 TB48 (I think for 100-160 Wh 2 spares and 1 in-aircraft are allowed, but not sure if more (less than 100) are allowed after that). The only issue now is that almost every single online store is out of them, so I guess I'll have to wait a while.

I'lm working on a battery rebuild video. I should have it and a how-to finished sometime in 2021.
 
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