High-speed rush to the sky

high-speed rush to the sky
please help me

[attachment=0]APM log.zip[/attachment]

Log shows a rise from 6mtr up to 55mtr but at the same time your throttle input goes to maximum.
You then cut throttle to 0 and switch to stabilise causing a rapid decent, throttle is raised and throttle output spikes probably to try and stabilise the uav. Then you have an altitude of -24.5mtr which is a bit worrying but the rest of it seems normal.