View Single Post
  #4  
Old December 15th 03, 12:53 AM
Peter Stickney
external usenet poster
 
Posts: n/a
Default

In article ,
"The Enlightenment" writes:

"Steven P. McNicoll" wrote in message
k.net...

"robert arndt" wrote in message
m...


http://www.heraldtribune.com/apps/pb.../APN/312130537

p.s. At least the GW No.21 replicas built by two different

historical
societies, in two different nations, at two different times, with

two
different pilots (one of which was a Luftwaffe pilot) flew easily.


No faithful replica of a Whitehead craft has ever been built or

flown by
anyone anywhere.


As I understand it this is only in the matter of the engines.
Whitehead/Weisskopf used steam engines. These apart from the expense
of replicating them also pose a safety hazard. On the occasion of the
first flight that very plausibly took place the vehicle crashed in
avoiding a 3 story building and the steam severely scaled the stoker.
Whiteheads aircraft also carried 2 people.


You're a bit off. While engine were a part of it, the real question
was stability and control. Well, (to paraphrase the Spanish Inquisition)
Stability, Control, and Experience. By Dec. 17th, 1903, the Wrights
had completed an intensive 4 year effort of kite tests, Wind Tunnel
experiments, and actual flight experience, all approached in a
methodical and scientific manner. By the time for their first powered
flight, they had more flight time than anybody else, and more accurate
knowledge of aerodynamics than everybody, all meticulously noted in
their journals. They also saved all of their development and test
test rigs, as well. It would be perfectly feasible to go to the Ford
Museum, where their shop and equipment are on display, and re-run
their experiments.

Whitehead's machine had no provisions for control, and somehow, we're
supposed to believe that he just hopped into his iarplane one day,
made a successful flight, and then hung it up to move on. (The same
goes for those making similar claims about some bloke in New Zealand.)

The "replica" isn't even that - it's a vaguely Whitehead
Machine-shpaced aircraft, with modifications made to make it somewhat
flyable. The rationalizations of the replica team, when this is
pointed out to them, are hilarious. "Well, we did make changes, yes,
but they are the changes that Whitehead would have made."Sure, if he'd
[known what he was doing/actually tried flying the thing/had bothered
to come up with better documentation that Friend of a Friend tales.]
Laughable.

His engines are interesting. He developed an 18hp aluminum steam
engine. It would be interesting to compare this to the Wrights cast
Iron petrol engine which because of its primitive state may very well
have had a lower power to weight ratio.


Well, it's very easy to make a light, powerful steam engine.
Somewhere around here, I've a picture of Sir Hiram Maxim holding up
one of the 100 HP triple-expansion engines for his captive test rig.
He was in his 70s at the time, so it certainly wasn't that heavy.
Light Steam engines are easy. Light boilers, water reservoirs, water
and fuel feeds, fireboxes, and reguating systems are not.

The Wright's engine, BTW, was cast Alumin(i)um, not Iron. The reason
that they built it themselves was that there weren't any light
stationary engines in the power range that they required. (16-10 HP).
But then, the Wrights knew that the key was efficiency, not raw power.
With their scientifically designed high efficiency propellers, they
were getting much more thrust out of 16 HP than anybody else was
getting from 30. That's another area where Whitehead's clains fall
over. The propeller design is horrendous. Nobody's claiming that the
Wright's engine was any particular mechanical marvel. The
Langley-Manley water cooled radial was an amazing engine. It produced
55 HP for a wight of around 200#, and was probably the best possible
engine in late 1903. Of course, that didn't ensure success for
Langley and Manley. (Manley was Langley's Mechanical Engineer, and a
brilliant one, at that. He was not only the powerplant designer, but
the test pilot, as well. Unfortunately, the Langley Aerodrome was
built without the thorough proving of basic priciples that the Wrights
used as their foundation, especially wrt stability and control, and
the total flight time of the Test Pilot, despite his extensive
theoretical knowledge, was the roughly 2 seconds/flight attempt that
it took for the Aerodrome to plummet into the Potomac from the roof of
Langley's houseboat. Note that despite his failure to fly, Langley
_was_ a cridible scientist with good credentials and a proven track
record, and Manley was a brilliant engineer and constructor.

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster