MakeFlyEasy Believer 4G/LTE - 6S6P 21,000mAh Battery Test

I've been sitting on this big battery for a few months waiting for some decent weather. Well today wasn't the day to push it but I still wanted to test. The goal here was to see how much voltage sag it has during takeoff. I've limited the throttle to 90% to keep power within spec of the motors so I was curious how the Believer would handle 90% throttle and voltage sag. The result: not bad at all. The winds were brutal so I just kept it overhead in a loiter for a bit. Telemetry was over 4G/LTE but I did not send video to save data. I have a feeling I'll be needing to bring a book on the long range flights.

Build List:
MakeFlyEasy Believer 1960mm Wingspan EPO Twin Motor Aerial Survey Aircraft FPV Platform Mapping RC Airplane KIT - https://usa.banggood.com/custlink/DDv...
Pixhawk Cube Orange - https://amzn.to/3zyuxe2
Pixhawk Here GPS -
2x KDE 2814XF 515Kv - https://www.kdedirect.com/products/kd...
2x APC 11x7 Props
2x Hobbywing FlyFun v3 40A ESCs
4x Emax ES3054 Servos - https://amzn.to/2FjkOkk or Banggood https://usa.banggood.com/custlink/vGK...
mRo I2C Airspeed Sensor JST-GH MS4525DO - https://store.mrobotics.io/mRo-I2C-Ai...
Mauch PL-100 Current and Voltage Sensor - https://www.mauch-electronic.com/apps...
Mauch 2-6S BEC / 2x5.35V - https://www.mauch-electronic.com/apps...
Benewake TFmini Plus Lidar Range Finder - https://amzn.to/3EPaWrV
Castle Creations CC BEC 10A 6S - https://amzn.to/30UA93k
Hawkeye Firefly Q6 Camera w/ battery delete. Wired to BEC - https://usa.banggood.com/custlink/DDv...
DMI to CSI-2 Adapter Board Module - https://amzn.to/340lntJ
Dorhea Raspberry Pi Zero Camera Ribbon FFC Cable - https://amzn.to/2E5VnC8
Raspberry Pi 3 B+ running Raspberry Pi OS Lite https://amzn.to/2DJCKEz and UAVCast Pro https://uavmatrix.com
SixFab Raspberry Pi 3G/4G/LTE HAT with Quectel EC25-AF modem - https://sixfab.com/
2x 4G LTE Low Profile Antenna SMA 4.6dBi - https://sixfab.com/product/lte-antenn...
Spektrum InterLink DX Simulator Controller (for 4G/LTE Control) - https://amzn.to/3kLq1Sf
RadioMaster TX16S Max - https://amzn.to/2MZ8xWc
Jumper R8 Receiver - https://amzn.to/3fYjzUz https://usa.banggood.com/custlink/m3D...