Having finally found time to read this thread (I've been meaning to ever since it popped up) I thought I'd add my 10 cents....
The perils of the low IAS, downwind maneuvers are well documented and hopefully all pilots flying out there are aware of the implications, if not perhaps a refresher flight with a instructor (and sufficient height agl) would be a wise investment.
VRS in a hover in a updraught, possible but unlikely as your power in use is probably considerably lower than in a normal hover (your in a updraught!), however if you start to sink a bit and decide to pull pitch......
To answer the initial post: if flying a constant radius turn around a ground feature at a constant IAS on a
nil wind day there will be no requirement for pitch change. Throw in some wind but fly at a constant IAS and pitch change will be needed as the angle of bank required to maintain the 'K' radius of the turn changes, otherwise the a/c will climb and descend as the associated load factor changes.
A question I have always pondered is where in the orbit is the demand for Bank Angle (and thus pitch/power) greatest??
Conventional Principle of Flight would mandate this be in the downwind position due to the squared function of velocity in the Load Factor equation as discussed by Nick Lappos in post #84. However when flying a constant radius turn at say 60 kts IAS in a 20 kts wind the greatest angle of bank
appears to be somewhat after the downwind position during the turn to crosswind? is this another illusion or due to the combination of high groundspeed (admittedly decreasing at this point in the turn but still higher than the IAS) and the drift caused by the (increasing) cross wind component...??
Any takers?