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I've been out of town for the last week, so I'm finally getting around to
replying to this.
Never tell a man that his girl is ugly or his airplane is slow. <ROTFLMAO!>
I forgot that little rule recently and the result is now a rich man (anyone
who has a loose $10k to gamble is rich in my humble opinion...) wants me to
find a Lancair, set up a sanctioned race course, and race his Chevy small
block filled with race parts against a "stock" TSIO-550. My last $10k went
into tooling for my aircraft; My next $10k will be going into fabrication.
I don't need to put up $10k to satisfy some rich man's fantasy when the best
sanctioned and observed air race course in the world exists right next door
to me. All race fans (not just myself) have been waiting 4 years for an
Engineair to show up at Reno and race against all comers like everyone else.
Looks like we'll be waiting a while longer.
Let's get some things straight. I didn't say that the "420 HP" Engineair
small block Chevy was not as good as a "350 HP" Continental, I said it wasn't
any better. I also said the "600 HP" big block Chevy Orenda (derived from a
Can-Am racing big block) wasn't any better. We don't know what the two newer
larger displacement efforts will do when they fly and race, and I made no
claims or comments about them.
I made the assertion that the Orenda was no better than the Continental based
on its performance of "running in the red" to stay ahead of a known stock
Lancair IV at the annual owners fly-in. The Lancair that had won for several
straight years had run a very consistent speed, and did so again. The
Orenda, "rated" at 600 HP had to redline to keep only 1 mph ahead. From this
I calculate that the Orenda is only good for the same power (or less) than
the stock Continental or has enough excess drag to discount any power
advantage. Please feel free to challenge this assertion; I am open to
alternative logic. I expected more from a $110,000 engine that turns a 4
place Lancair IV into a 2 place with its excessive weight. I would certainly
recognize that the Engineair is at least cost competitive with the stock
Continental; something we can't say for the Orenda.
In cross country race after race, the factory Engineair (N420HP) has
performed within a few percent of many Lancair IV's equipped with TSIO-550's;
sometimes slightly faster, sometimes slower, most of the time about the
same. One might debate the state of tune of the Continentals competed with
was not "stock" or they were not being run under conditions that they could
reach the book TBO. One might question that of any entry, including N420HP.
We do know that the entry we worked on (Lee Behel's Venture) had a dead
stock, non-turbo, PMA manufactured IO-550 and only our aero mods and went 3
mph faster than N420HP in the 2000 Dayton to Oshkosh race. It also did this
with the primary GPS taking a dump and Lee's 9 year old son running
supplemental navigation on a hand held. <LOL> I personally feel Lee is one
of the best pilots I know, however to attribute this victory over N420HP
solely to a difference in skill or luck is ridiculous; no race is perfect,
and everyone has their problems including the winner. Lee and his son still
managed a 315 mph average there and a 311 mph average at the 2001 Sun 100 (a
record speed for that race I have been told). They also ran an entire week
at Reno in the same trim at 309 to 311 mph around the Sport Class course at
density altitudes from 6,000 to 8,500 ft. while a stock Venture ran within 1
to 2 mph of Lee's baseline from 1998 when his aircraft had no aero mods
except taped gap seals. From this, we can pretty much say that we know what
Lee's airplane is good for in it's current form in cross country and pylon
racing. If he changes nothing, I would be very surprised at any finish in
any cross country race (of reasonable length and running with and against the
winds aloft) outside of 310 to 316 mph.
In the coverage of the 1999 Kitty Hawk to Osh race, Jim Rham gave the
following commentary of his second leg:
"The upper winds were still strong, so I elected to stay at 4,500 ft. I flew
the airplane at 35.5" MAP and 4,200 engine RPM, which is about 97% power...
...At 4,500 ft. we had around 12 knots of wind on the nose most of the way
and my groundspeed was 235 to 242 knots most of the time."
I have no reason to doubt these figures since they correlate well to several
other races that N420HP has competed in. So let's break this down.
242 and 235 ground speed with a 12 knot head wind averages to 250.5 KTAS or
287.5 mph TAS (Jim did not give a KTAS, we are calculating this from his wind
quote). At 4,500 ft. in an ISA atmosphere, this translates to 230.7 KIAS at
the "97%" power level. Simple power vs. speed conversion to 100% power
yields ~233 KIAS from a claimed 420 HP. Note that we are being very generous
here; if the OAT was anything higher than an ISA standard 43 degrees F, the
density altitude would be higher and the IAS lower. So I am granting a great
deal of performance margin in these calcs that probably isn't there. With
the higher temperature that other participants have told me was present in
that race, the IAS would drop by at least 5 KIAS for the quoted altitude.
In pylon racing (at Reno, on a sanctioned and observed course) a stock
Lancair IVP with no mods is good for 280 to 285 mph (218 to 221 KIAS
depending on density altitude). It's a narrow range because only a couple of
people have tried it so far. The rest of the Lancair's flown around the
pylons have been highly modified, so we are not counting those to be fair to
Engineair.
In cross country racing, the same aircraft are good for 280 to 305 mph
(discounting the 2000 Oshkosh winner as a "non-stock" entry based on
Engineair's opinion). Clearly, the Venture loses less on the pylon course
vs. cross country when compared to a Lancair and no matter how good the
piloting, most of this is due to the higher aspect ratio wing. The wide
range of 225 to 240 KIAS reported from TSIO-550 Lancairs for these cross
country races corresponds to a wide range of participants, and relative
engine/aircraft variations. This correlates well to the 220 to 240 KIAS that
most new TSIO-550 equipped Lancair IVP builders claim at 100% power under
5,000 ft. The high end would correspond to a carefully detailed aircraft
like N420HP.
I have also NOT included two Lancairs that raced at Reno with extensive
modifications. Only the unmodified, no spray bar water, no ADI entries are
used for this comparison. No excuses there.
So we end up our comparison (as of June, 2001) with the Engineair at 228 to
233 KIAS and the "stock" Lancair IVP's at 220 to 240 KIAS. There are more
TSIO-550's flying than Engineairs, so we only have the prototype for
comparison. This prototype falls in the middle of the range of the "stock"
TSIO-550's. So we would expect that if N420HP ever came to Reno and raced on
an observed, sanctioned race course, its performance would be virtually
identical to Lancair IV's equipped with TSIO-550's.
Yes, all the Continental owners are over-revving and over-boosting their
engines. So can Engineair. All's fair in war and racing. I eagerly await
an Engineair equipped Lancair shattering the speeds that TSIO-550 Lancair
IV's have proved time and time again. It hasn't happened yet; Orenda didn't
do it either. I had a builder ask me the other day what I would recommend
for an engine and I said, "can you wait 6 to 12 months?". That should be
time enough for the customer built Engineair aircraft to beat (or not) the
factory performance; time for the other two big displacement engines to fly
and beat (or not) all the Continentals; time for a FADEC and ceramic
equipped Continental to beat (or not) all the stockers; and time for a few
of the Walter turbines to debut and everyone to see just how much fuel they
really burn for all that power, and how much power they have left at altitude.
Since this race challenge is coming from a member of the Engineair LLC group,
we really have no idea of the state of tune the engine would be in. It is
doubtful that it or any other engine in any challenge race will be one that
has seen "TBO" or will be run at a power level that could reach "TBO". In
the meantime, I will sit next to our fully timed, measured, sanctioned,
officiated race course, watch and publish the results, the mods, and the
cost, as I did this year in Kitplanes (June 2001 issue, pg 20). Concerning
gambling, I am in one of the world centers of gambling and no where else will
you see so much BS attached to so much money; walking, talking or not.
In SANCTIONED PYLON RACING, when the flag drops, the BS stops.
Eric Ahlstrom,
Race fan, driver, engineer, and armed with a calculator and stopwatch....
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LML website: http://www.olsusa.com/Users/Mkaye/maillist.html
LML Builders' Bookstore: http://www.buildersbooks.com/lancair
Please send your photos and drawings to marvkaye@olsusa.com.
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