Rate of Climb
I have the aircraft performance data and as I said in my original post I get a substantially different expected rate of climb from the data sheet inputting the information from the flight as I understand it, bringing the aircraft well within the expected climb performance. Unless I have got this totally wrong. The engineer has rechecked the aircraft and says there is nothing wrong with the engine performance/prop etc. The aircraft has recently been reweighed. As yet we haven't managed to speak to the pilot undertaking the test. So my question stands using the performance data sheet my suspicion is that there may have been a miscalculation in ISA temp of +5C explaining a difference in 100' climb performance. The aircraft is awaiting a repeat of the climb performance element of the airtest.