From the FCTM AO-034,
If the FPV is reliable, or if the GPS altitude information is available:
‐ Maintain level flight (FPV on the horizon or constant GPS altitude),
‐ Adjust thrust according to the table,
‐ Observe the resulting pitch attitude, and compare it with the recommended table pitch
target:
• If the aircraft pitch necessary to maintain level flight is above the table's pitch target,
the aircraft is slow, then increase thrust,
• If the aircraft pitch necessary to maintain level flight is below the table's pitch target, the
aircraft is fast, then decrease thrust.
When the pitch required to maintain level off gets close to the table pitch target, re-adjust
thrust according to table thrust target.
This technique enables to quickly stabilize the speed, while maintaining level flight.
If the FPV is not reliable and the GPS altitude information is not available (no means
to ensure level flight):
Adjust pitch and thrust according to table, and wait for speed stabilization. Expect a
significant stabilization time and important altitude variations