Backpacker siad:
... Deploying flaps has a number of effects:
- ...
- It changes the average angle of incidence of the wing, initially leading to a pitch up, but eventually resulting in a lower fuselage angle of attack for the same wing angle of attack, and this results in a better view over the nose and a reduced risk of tailstrikes.
As a rule of thumb, (going back to Prandtl in the 1920s IIRC) deploying X degrees of flap without rotating the aircraft increases wing Angle of Attack by X/2 degrees. So if half the wing is flapped, and you add 30 degrees of flap, you should pitch 7.5 degrees down "theoretically" to maintain lift.* This pitch down is independent of whatever you need to do to the elevator to re-balance the pitching moments.
Of course with flaps down (and a lower stall speed) you can hold off at a high pitch and slow speed, and the nose wheel is no more vulnerable for having flaps down. Unless you are much too fast...
In any given configuration, extra speed in the hold off means lower pitch and a more exposed nose wheel. I learned to fly at a bumpy grass strip and the FIs would get quite grumpy about coming in too fast
*Conversely, the need to pitch up when you retract flaps makes this a very hazardous manoeuvre at low speed near the ground.