Hi !
Ivan Shaw labeled this way of cruise-setup "flying on the step" - a term that he
derived from floatplane flying. He recommended to perform all measurements after
a shallow dive or a run at higher rpm.
I had much time to verify this theory during my Ocean crossings. It is only a
temporary
effect. After some 10 minutes of flying the plane will settle to the
same speed as if you had come from the lower side of the curve.
Yet this discussion makes me think... people are stating very impressive speeds.
My Europa will - after all improvements - stop accelerating at 124 knots IAS
(2000 ft, standard day). It is a Europa Classic with a 912 and an Airmaster
prop.
It feels like an aerodynamic barrier to me. Yet in a dive she will quickly
reach 140 kn.
I did not make very good measurements, but I am positive to have obtained a 10
kn gain from the speed kit along with taping over the wing-to-root joint.
Only after those mods did she obtain the self-set goal of 1oo kn @ 10 litres/hr.
Sincerely,
<Thomas, N81EU>
----- Original Message -----
From: MJKTuck@cs.com
Subject: Speed Kit
Hi Folks,
One thing I noticed when I fly is if I level off at - say - 3,500 ft let the
speed build, throttle back to say 5,000 rpm I get around 115 kt indicated. If
I climb to 3,600 ft first then gently point the nose down to bring me back down
to 3,500 ft and let the airspeed gets up to around 125 kt indicated, throttle
back to 5,000 rpm the airplane settles back to 120 kt indicated (where it
stays).
Don't know if its some weird aerodynamic thing but it seems by pushing it
over its normal cruise speed first then letting it settle back to its own cruise
speed, you get a few knots more than if you were to let it make its own way
up.
I haven't taken any scientific measurements just an observation of the ASI.
Anyone else found this? Any ideas?
Martin Tuck
N152MT
Wichita, Kansas
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