Omaha daily bee., 1908-08-11
BALDWIN IS SURE OF SPEED
Confident His Dirigible Will Test
Twenty-Five Miles an Hour.
OTHER EXPERTS ADD TESTIMONY
MathemRtIcInnS Figure with Loss of
HnIf of speed Balloon should
Fly Thirty Miles an
Hour.

WASHINGTON. Aug. lot is not OK
pected that the official speed test Of Cap
tain Thomas s. Baldwin's dirigible bal
loon will be held at Fort Mycr today a.
has been announced. Glenn II. Curis. the
builder of the motor. who went to Ham
mondsport. y. V. on Saturday 10 get four
carburetors for the motor. wired Cap ain
Baldwin last night that he would prob
ably be unable TO start for Washington
until today.
The failure or Captain Baldwin to at
tempt the speed trial on Saturday. az he
had announced, was taken by some to In
dicatc that he could not make tho speed
requirement Of sixteen miles an hnur.
When questioned Captain Baldwin said:
"Tt has a. no time occurred to me that
would not fulril the speed requirements.
| am satisfied that we will make twenty
two miles an hour n tie official trial
I'm our test Of the motor and propeller
at Hammondsp0rt we found that we had a
maximum pulling power Of $50 pounds.
The shape Of my gas envelope reduces the
resistance to a minimum; in fact what
ever head resistance there is 10 Compen-
stated for by the tapering Of the bag toward
the rear end. The skin resistance and the
resistance offered by the ropes, the frame
and the operators is nTttllCallN all mat
remains to be cOntended with.
There are any number of other things
which come into play, but not being a
scientific man | cannot explain them.
have learned the theory from the practice. -
Experts Figure Out speed.
Prof Henry H. Clayton, the mcteorologist
and acronaut; John McCurdy Of the Aerial
Experiment association and Augustus Post
secretary Of the Aero club, figured out the
speed which Captain Baldwlns airShio
should make as twenty-five miles an hour.
The diameter Of Captain Baldwin's gas
bag is nineteen feet a its widest point
and the nose or frame END is nineteen feet
forward of the widest part. This gives the
forward end a conCa shape.
According to Prof Zahm's theories and
the generally accepted law which has been
repeatedly proven" said Mr. Post, "the re-
sistsnce of 4 flat surface is reduced one
half when the surface is changed td the
shape OF q sphere. If elongated into a
conical shape it is reduced To less than
one-third the resistance offered by TN
flat surface"
Then" said Prof Clayton as he made
some mathematical calculations. "Captain
Baldwin's ship has a sectional area of 2si
square feet with flat surface, but with
its present shape this is reduced to ninety
five square feet This would REQUIRE a
pull Of l9O pounds to maintain a speed ol
twenty miles an hour. With an av,rag,
pull of 24O pounds and with allowance
made for skin resistance and other condi-
tions. the airship should develop speed
Of twenty-five mues an hour"
Mr. McCrIdy was OF the SAM opinion
The theoretical speed is nearly sixty m les
an hour" he said, "and II as much as 81
per Gent ot this is lost, there would stIl 10,
speed Of thirty miles an hour. In addi-
ton tie test at which a pull Of IS pounds
was recorded was made in stll air. but
when the snip is moving in the air greater
efficiency is gotten as the propeller con
tinuallv gTasps new air