GPS Altitude and Altitude accuracy data
| Channel Number | 57 |
| Total Length | 10 bytes |
| Channel | Data1 | Data2 | Data3 | Data4 | Data5 | Data6 | Data7 | Data8 | Checksum |
GpsAltitude (mm above sea level) = (Data1 x 2^24 + Data2 x 2^16 + Data3 x 2^8 + Data4)
Altitude accuracy (mm) = (Data5 x 2^24 + Data6 x 2^16 + Data7 x 2^8 + Data8)