If you want to do this sort of thing, get some aerobatic instruction.
And do it in an acro aircraft. As you describe what you want to do,
it has a definite "Hey, watch this" ring to it. It's POSSIBLE to do
acro in a normal/utility category plane - as Bob Hoover has shown -
but you have to be VERY good if you're not going to break
anything. (Also it's illegal unless you reclassify the aircraft as
experimental, which brings a whole lot of other restrictions).

You should definitely not try ANY of this stuff unless you have
done some proper spin recovery training. A 172 is legal and safe to spin
(if loaded correctly) but if you haven't experienced a spin there
is a serious risk that you will panic. None of us wants to read about
you in an NTSB report.

That said... a 2G 60 degree banked turn is no big deal. Presumably
you have already done 45 degress (1.4G). Bank a bit further and
pull hard enough to maintain level flight. In a 172 it requires a fairly
strong pull but no huge deal (unlike the 182). Use the AI and
altimeter to keep track of what you're doing. Be VERY careful not
to bank a degree more than 60 degrees. At 70 degrees you are at
the limit of what the plane can take.

Floating in a 172 will stop the engine, and if you go even slightly
negative for more than a fraction of a second, will also cover the belly
of the plane with oil. This will not make you popular with the FBO.
As long as you push gently and stop before you hit zero G, nothing
bad will happen.

As soon as you start doing things like this you risk stalling and spinning.
You need to have an instinctive recovery action from an incipient
spin (opposite rudder), which takes a bit of practice - with a
spin-experienced instructor sitting beside you.

Get some acro training. It's loads of fun and will mean you can do
"extreme" non-acro stuff like this with no risk

John


"Koopas Ly" wrote in message
om...
Me again,

Va seems to be only intended to protect against excessive positive
load factors. What about negative g's?

Can I find a Va for negative design load factors (-1.52 g) for the
C172SP anywhere?

Reason I am asking is that I want to try the "floating pencil" trick
next time I fly but I don't want to shove the stick fully forward for
fear of breaking something. I am not looking to induce negative g's,
only zero g's and zero lift. Any pointers on entry speed and power
settings? Is it easier to perform if you induce a gradual +1 g steep
climb similar to a departure stall maneuver, then upon hearing the
stall horn, give it good nudge forward on the stick? I've heard that
your airspeed may indicate well below stall, but again, your stall
speed does approach zero as your load factor goes to zero.

Likewise, would you prefer to pull 2 positive g's in a pull-up
maneuver or a, say, 60 deg. bank? Frankly, I am not too familiar with
the former so I might do something undesirable. Aside from my stall
speed going up to something like 68 kts. clean (Va ~ 100 kts), you'd
see your airspeed quickly dwindling while pulling up. I think it'd be
fruitless to add in power since heck, you're not maintaining altitude
and besides, you probably don't have any excess power anyway to do
that. Neither am I familiar with the mechanics of loops so it'd be
wiser to leave that alone. Perhaps the 60 deg. bank is more
reasonable to have some fun. Would you try to hold altitude with
backpressure and power or just leave the plane to dive and speed up in
the spiral, with a recovery before Vne? I think the maneuver would be
more innocuous with power-off a-la-emergency-descent style. Again,
I've never done a 60 deg. bank...so I should probably leave that alone
too until I try it with a passenger...oops..i mean CFI.

Seriously, if someone has something to suggest that's fun and safe,
within normal operating range and category, please suggest. It's a
buddy's bday soon and he wants to go up. Again, I am not looking for
doing anything aerobatic.

Alright, I can see the flames and derision coming from the mainland

May you have a peaceful week with no stress,
Alex