text: The indirect effects of power are of greatest 
  the propeller powered airplane 
  concern in 
  rather 
  the jet powered airplane. As 
  than 
  shown in figure 4.12, the propeller powered 
  airplane creates slipstream velocities on the 
  various surfaces which are different from the 
  flow field typical of power-off flight. Since 
  the various wing, nacelle, and fuselage surfaces 
  immersed in this slip- 
  are partly or wholly 
  stream, the contribution of these components 
  to stability can be quite different from the 
  power-off 
  the 
  change of fuselage and nacelle contribution 
  with power is relatively small. The added 
  lift on the portion of the wing immersed in 
  the slipstream requires that the airplane oper- 
  ate at a lower angle of attack to produce the 
  same effective lift coefficienr. Generally, this 
  reduction in angle of attack to effect the same 
  to stability. 
  CL reduces the tail contribution 
  However, the increase in dynamic pressure at 
  the tail 
  tends to increase the effectiveness of 
  the tail and may be a stabilizing effect. The 
  magnitude of this contribution due to the 
  slipstream velocity on the tail will depend on 
  the c.g. position and trim lift coefficient. 