Inlet air pressure during free fall in android

I am writing an application to log some data for skydiving. I have 3 modes: -Ground (recalibrating air pressure at ground level) -Flight (rapidly decreasing air pressure) -Jump (rapidly increasing air pressure) I get the sensor values ​​via a registered SensorEventListener

 @Override
public void onSensorChanged(SensorEvent event) {
    Log.d("currentStatus", currentStatus.toString());
    long currentTime = System.currentTimeMillis();
    switch (currentStatus) {
    case GROUND:

        if (lastCheck == null || lastCheck.getTimestamp() < currentTime - 30000) {

            if (lastCheck != null && Calc.getAltitudeByPressure(lastCheck.getPressure(), event.values[0]) >= 30){
                currentStatus = Status.FLIGHT;
                groundlevel = lastCheck;
                pw.println(currentTime+": Status wechselt: Flight");
            }
            else{
                Log.d("Kalibirierung", event.values[0] + "");
                pw.println(currentTime+": Kalibrierung: "+event.values[0]);
            }

            lastCheck = new EnvValues(currentTime, event.values[0], 0);
        }
        break;
    case FLIGHT:
        lastCheck = new EnvValues(currentTime, event.values[0], 0);
        pw.println(currentTime+": Aktuelle Höhe: "+Calc.getAltitudeByPressure(groundlevel.getPressure(), lastCheck.getPressure()));
        break;

    case JUMP:
        break;

    }

}

      

        
        
        
      

    

It works on the ground and climbs perfectly, some logdata ("aktuelle Höhe" means current altitude in meters):

1438424661607: Kalibrierung: 1006.6233
1438424756674: Status wechselt: Flight
1438424756674: Aktuelle Höhe: 81
1438424756674: Aktuelle Höhe: 348
1438424756674: Aktuelle Höhe: 349
1438424756674: Aktuelle Höhe: 348
1438424756792: Aktuelle Höhe: 349
1438424756991: Aktuelle Höhe: 349
1438424757191: Aktuelle Höhe: 354
1438424757391: Aktuelle Höhe: 354

      

        
        
        
      

    

But when lowering the altitude and during free fall, he writes:

1438425939005: Aktuelle Höhe: 3953
1438426040917: Aktuelle Höhe: 3952
1438426040917: Aktuelle Höhe: 3953
1438426040917: Aktuelle Höhe: 749
1438426040917: Aktuelle Höhe: 747
1438426040917: Aktuelle Höhe: 747
1438426040917: Aktuelle Höhe: 747
1438426041052: Aktuelle Höhe: 746
1438426041195: Aktuelle Höhe: 745

      

        
        
        
      

    

there is no freefall registration, and the time stamp remains the same before and after the dome is opened.

Here is a link to the log file (its very large): Link to the log file

In the log file you can see the height of the ascent to the lowering height (the plane was for a long time at a fall height of 3950 m), the next value is 749 m. Data for 1 minute of free fall is completely absent. does anyone know what is going on here?