Does needing IMU recalibration mean a bad bird?

[blade_runner]

Hi Folks,

A guy just purchased my Phantom V1 but could not get GPS to calibrate after unboxing it and attempting to in the field. It would not start the props up either.

Anyway, he called me and I drove over, picked it up, brought it home and after I did an an advanced IMU calibration, it immediately started up, calibrated, locked in, and flys fine. The props not starting up was not surprising since DJI says if "sensor error is too big, the system will not work".

HOWEVER, he now tells me that he has "lost confidence" in it because it had to have the recalibration. I explained to him that any precision instrument needs to be recalibrated at times, but he is adamant that the Phantom is now unreliable.

So... I'm short on reasons why IMU would need to be recalibrated. Is it because I traveled from NY to Florida which is where I dropped the Phantom off to him at?

It wasn't dropped or treated roughly. Adult owned and operated, named "Betsy" and cared for gingerly. Only one IMU calibration done the first week I owned it (three months ago) and has approx. 30-40 hours of unremarkable (except for great videos!) flight time.

Do you think there's any reason to be suspicious of the Phantom's future performance?

Thanks much for any input.

 

[rmklaw]

No. I recalibrated a Vision, a Phantom 2, and my brother in law's F40. Also, my F550. They all fly impeccable.

 

[blade_runner]

Thanks, Richard.

 

[OI Photography]

If the guy wants to make assumptions like that without understanding how the factors at play work, maybe it's better he's not flying in the first place

 

[ElGuano]

I think everyone knows the answer to this one

Very generally, an IMU calibration is kind of like an oil change on a car. Needing one doesn't mean you're driving a lemon. I figure some people are coming into the hobby with the assumption that the Phantom doesn't/shouldn't need any maintenance. Hopefully he doesn't throw out his iphone every time the compass app tells him to make the figure-8 motion!

 

[The Editor]

If the guy wants to make assumptions like that without understanding how the factors at play work, maybe it's better he's not flying in the first place

+1

 

[WReimer]

I agree with the others. It sounds VERY much to me like someone who has never flown anything before, has no clue, and is having buyers remorse; either feeling like he's in over his head and looking for a way out with his ego intact, or his wife/girlfriend/significant other nixed the idea, and he's looking for an out with an intact ego, etc.

Sadly, with someone like that there is very little chance that you'll change his mind. If you defeat the IMU argument, I bet he comes up with something else that's a deal breaker. He probably shouldn't fly, at the end of the day. I've seen people like that before ( I'm sure we all have), and it's often easier to just give them their money back, and list it again. It's not like they're hard to sell.