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It was 922F.
Given this discussion,
I'd suggest a slightly different approach.
Most of the Legacys run
in the 240-250kt range (those quicker ones anyway).
If indeed this one is in
the mid 260's, I doubt subtle changes to the bodywork to better match wing
airfoils is the magic as that is a 15kts differential from the 250 mark (which
very few stock legacys make)
This particular airplane
makes that mid 260 number on 19.5 gph (the owner had a card in the airplane with
the specifics). It gave no MP/RPM numbers however.
Also, it has a highly
modified LyCon IO-550 engine with 10:1 compression and a supposedly dyno'd
375HP. I heard a rumor that it actually made 390 on the dyno and had to be
"turned down" (dunno how you do that with a normally aspirated engine) to make
the 375HP.
As everyone knows, the
only semi accurate way to determine accuracy in TAS numbers is to use a
spreadsheet by the National Test Pilot association, here's the link http://www.ntps.edu/Files/GPS%20PEC.XLS
Use the tab that requires
4 legs. It's pretty simple to do this, just pick an altitude where you can
make 75% power, setup for your runs and level out and let your speed
build. Now turn on your Autopilot and slave it to the GPS. You want
to fly 90 degree legs (90, 180, 270, 360) all 4 of them.
For each leg, write down
the following information
Alt, RPM, MP, OAT, PALT,
DALT, IAS, TAS (if you have onboard indication), GPS TRACK, and GPS GROUND
SPEED
Now when you have landed,
plug in the GPS TRACK and the GPS GROUND SPEED into that 4 leg tab on the spread
sheet and see what the TAS was. If it is higher or lower than your
indicated TAS, then you have an error in your IAS (which is what feeds the TAS
CALC in most GLASS panels), or your OAT.
I did notice that this
particular airplane had GRT Glass panels in it and that it used a slightly
different ram air setup.
As a note, Scott Alair
ran the AVC at 297mph or 253kts in a stock engined legacy, but I believe he was
turning 2900 RPM and I don't know what his MP was. Last year at reno, a
legacy right out of build assist with no paint or body work turned 290mph laps
at reno but this one also had a modified motor from performance engines altho it
turned stock RPM (2800).
The reason I make these
last 2 points. HP is king when trying to put up speed numbers. So if
the mid 260's is everything full forward, what is the typical cruise in this
airplane with a more standard fuel burn? That will tell probably more as
it relates to speed than a speed run will.
My .02,
Alan
What is Mr. Frazier's N Number?
Jeff
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