The placard doesn't say you can't sideslip with flaps. The POH says...
Ok. I dont want to get in a hair splitting contest over this, but I didn't say that sideslipping with flaps was prohibited, only that it should be avoided, as the placard says, and for the reasons I have stated.
I have played around with sideslipping cessnas with flap a lot for 'fun' when I was younger, and experienced both the sudden onset of quite severe pitching oscillations and aileron restriction. As slam says, ASI variation can be a feature of sideslipping in general, but seemed to me to be more evident on the 172.
I guess the flaps moving sideways was one of the reason that Cessna introduced the SID's checks
I guess it may be part of it. Sideslipping with those big flaps at the end of those long tracks must be quite fatiguing.
Just remebered a big plus for the Cessnas. They are a lot nicer to get in and out of when it's pxxxxxg with rain!
MJ
