Replies to This Discussion

Permalink Reply by Matt Pope on April 13, 2022 at 11:42am

A few thoughts...

The first thing I would look at is the center of gravity. Moving the CG rearward (within design limits) results in a lower nose attitude because less down force is required at the tail to maintain level flight, so the wings don't have to create as much lift and the aircraft can maintain altitude with the wings at a lower angle of attack (lower nose attitude). This is counter-intuitive - people tend to assume that a nose heavy aircraft would have a more nose down attitude, but it's the opposite - every pound of down force produced by the tail to balance the heavy nose is another pound the wings have to lift, and they do that by flying at a higher angle of attack (nose up). Moving the CG rearward also increases cruise speed and fuel efficiency because there's less induced drag, and it decreases stall speed because there's less down force on the wing - lots of reasons to prefer a rearward CG. It needs to be within design limits though, otherwise a stall/spin could be unrecoverable.

If the CG isn't forward, then consider increasing the wings' angle of incidence relative to the fuselage. That would result in a greater angle of attack for a given nose attitude, allowing the aircraft to cruise with a lower nose. Changing the angle of incidence would require re-rigging the wings though.

When you lower the flaps you lower the nose to maintain level flight. Adding a small amount of droop to the flaps and ailerons would increase the wings' effective angle of incidence by lowering the trailing edge (but it would also increase drag).

• ▶ Reply

Permalink Reply by Jerry Latimer on April 16, 2022 at 7:37pm

Installation of VG's on the wings lowered my 601HDS's nose during cruise.

• ▶ Reply