Originally Posted by
TacomaSailor
11 seconds with 00' elevation gain (to 7,225') and acceleration from 105 to 154 knots
11 seconds with 25' elevation LOSS (to 7,200') and acceleration from 154 to 183 knots (did ETH-402 try to lift off runway and then settle back on to it?)
Bear in mind that ADS-B altitude granularity is 25ft, you won't see smaller increments than that. So it may only have dropped by a few feet but that is rounded to -25ft.
Also the altitude reported in ADS-B depends on the message type being parsed; some use the barometric pressure from the Mode-C source to calculate altitude per 1013hPa*, whereas others use the GNSS height corrected to WGS84. There's no AMSL data from ADS-B.
* aircraft at my local airport regularly land at -200ft per message type 7