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ACRO E-mail Archive Thread: [Acro] RE: Push up hammers

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ACRO E-mail Archive Thread: [Acro] RE: Push up hammers


Thread: [Acro] RE: Push up hammers

Message: [Acro] RE: Push up hammers

Follow-Up To: ACRO Email list (for List Members only)

From: Jeffrey Lo <jlo at>

Date: Mon, 24 Jun 2002 01:09:01 UTC


  Could it be that you still have enough lateral velocity while vertical that
the prop wash is being blown "below" the belly of the airplane and away from
the rudder, thus reducing your rudder effectiveness?

Jeff Lo
jlo at
1988 Pitts Special S1S

-----Original Message-----
From: Klein Gilhousen [mailto:kleing at]
Sent: Saturday, June 22, 2002 8:42 PM
To: acro at
Subject: [Acro] Push up hammers

Today I was out practicing the Advanced known sequence in my Extra.  There
are two push up hammerheads in this sequence.  I've been trying to keep my
negative g exposure to a minimum so I was only pushing about -2.75 g.  With
a 120 knot entry speed (the preceding figures only give me about this much)
I am going about 70 kts once I achieve the vertical.  The problem is that
when I kick it doesn't seem to want to go.  On a normal hammerhead, I
normally kick when the airspeed hits 40 knots indicated.  This gives a
nice, consistent pivot.  But kicking at 40 knots after a push up seems not
to be working very well.  I was pivoting to the left in both cases.  So
what's up with this?

Klein Gilhousen, IAC 21489
Bozeman, MT


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