There may be insufficient forward pitch control available to keep the aircraft level.

There may be a tendency to over-pitch the aircraft during the flare just before landing.

There may be insufficient aft pitch control available to keep the aircraft level.

The aircraft may become excessively manoeuvrable and beyond control.

an improved angle of climb and increased obstacle clearance

a reduction in the fuel flow and endurance

an increase in the fuel flow and specific range

a reduction in the rate of climb and the range