engine which has been used abroad to considerable degree of success.
Owing to the difficulty in constructing and operating a steam driven
engine, very few model flyers in America have devoted any attention
to the development of this engine as a means of propulsion for model
aëroplanes. But irrespective of the limitations of the steam engine
a great deal of experimentation has been carried on in England, and
without doubt it will soon be experimented with in America.
H. H. GROVES STEAM POWER PLANTS
Perhaps one of the most successful steam power plants to have been
designed since the development of the Langley steam driven model, is
the Groves type of steam power plant, designed by Mr. H. H. Groves, of
England. On one occasion several flights were made with a model driven
by a small steam engine of the Groves type weighing 3 lbs. The model
proved itself capable of rising from the ground under its own power and
when launched it flew a distance of 450 feet. This is not a long flight
when compared with the flight made by Prof. Langley’s steam driven
model on November 28, 1896, of three-quarters of a mile in 1 minute and
45 seconds, but the size of the models and also that Mr. Groves’ model
only made a duration of 30 seconds, must be considered. The model was
loaded 12 ounces to the square foot and had a soaring velocity of some
20 m.p.h. The total weight of the power plant was 1¹⁄₂ lbs. Propeller
thrust 10 to 12 ounces. The total weight of the model was 48 ounces.
The type of steam plant used in connection with this model was of the
flash boiler, pressure fed type, with benzoline for fuel.
Mr. Groves has done considerable experimenting with the steam driven
type power plant. Many of the designs used in the construction of
steam plants for models are taken from his designs. A Groves steam
power plant is employed in one of Mr. V. E. Johnson’s (Model Editor
of _Flight_) model hydroaëroplanes, the first power-driven, or
“mechanically driven” model hydroaëroplane (so far as can be learned)
to rise from the surface of the water under its own power. This model
has a total weight of 3 lbs. 4 ounces.
G. HARRIS’S STEAM ENGINE
Another advocate of the steam driven type model is Mr. G. Harris, also
of England. Several good flights were made by Mr. Harris with his
pusher type monoplane equipped with a steam driven engine. As a result
of his experiments he concluded that mushroom valves with a lift of
¹⁄₆₄ part of an inch were best, used in connection with the pump, and
at least 12 feet of steel tubing should be used for boiler coils. The
first power plant constructed by Mr. Harris contained a boiler coil 8
feet long, but after he had replaced this coil with one 12 feet long,
irrespective of the fact that the extra length of tube weighed a couple
of ounces, the thrust was increased by nearly a half pound.
[Illustration: An English steam power plant for model aëroplanes.
Courtesy _Flight_.]
[Illustration: Model hydroaëroplane owned by V. E. Johnson, Model
Editor of _Flight_, England, equipped with an H. H. Groves steam power
plant. This model is the first power driven—as far as can be learned—to
rise from the surface of the water under its own power. Courtesy
_Flight_.]
The principal parts used in Mr. Harris’s steam power plant was an
engine of the H. H. Groves type, twin cylinder, ⁷⁄₈″ bore with a piston
stroke of ¹⁄₂″. The boiler was made from 12″ of ³⁄₁₆″ × 20″ G. steel
tubing, weighing 10.5 ounces. The blow lamp consisted of a steel tube,
⁵⁄₃₂″ × 22″ G. wound round a carbide carrier for a nozzle. The tank was
made of brass ⁵⁄₁₀₀₀″ thick. The pump, ⁷⁄₃₂″ bore, stroke variable to
¹⁄₂″, fitted with two non-return valves (mushroom type) and was geared
down from the engine 4.5 to 1.
PROFESSOR LANGLEY’S STEAM ENGINE
The Langley steam driven model, of which so much has been said, and
which on one occasion flew a distance of one-half mile in 90 seconds,
had a total weight of 30 lbs., the engine and generating plant
constituting one-quarter of this weight. The weight of the complete
plant worked out to 7 lbs. per h.p. The engine developed from 1 to 1¹⁄₂
h.p. A flash type boiler was used, with a steam pressure of from 150
to 200 lbs., the coils having been made of copper. A modified naphtha
blow-torch, such as is used by plumbers, was used to eject a blast or
flame about 2000 Fahrenheit through the center of this coil. A pump was
used for circulation purposes. With the best mechanical assistance that
could be obtained at that date, it took Professor Langley one year to
construct the model.
FRENCH EXPERIMENTS WITH STEAM POWER PLANTS
About ten months after Langley’s results, some experiments were carried
out by the French at Carquenez, near Toulon. The model used for the
experiments weighed in total 70 lbs., the engine developing more than
1 h.p. As in the Langley case, twin propellers were used, but instead
of being mounted side by side, they were mounted one in front and the
other behind. The result of these experiments compared very poorly with
Langley’s. A flight of only 462 feet was made, with a duration of a few
seconds. The maximum velocity is stated to have been 40 m.p.h. The span
of this model was a little more than 6 meters, or about 19 feet, with a
surface of more than 8 square meters, or about 80 square feet.
[Illustration: An English hydroaëroplane of tractor design equipped
with steam power plant. Courtesy _Flight_.]
[Illustration: On the left an English 10 oz. Compressed air driven
biplane. On the right, the engine shown fitted with a simple speedometer
for experimental purposes. Courtesy _Flight_.]
CARBONIC GAS ENGINE
The six-cylinder carbonic gas engine described herewith is the product
of Mr. Henry Rompel, Kansas City, Missouri.
This is perhaps one of the most interesting of its kind to have been
developed during 1916, and its appearance in the model aëroplane field
adds weight to the claim that mechanical engines will soon replace the
rubber strand as motive power for model aëroplanes.
Mr. Rompel’s engine is of rotary, carbonic gas type, having six
cylinders, a bore of ⁵⁄₈″ and a stroke of ³⁄₄″.
The intake is derived through a rotary valve which also acts as a crank
shaft bearing, thereby saving weight.
The exhaust is accomplished by mechanically operated valves situated in
the heads of the cylinders being opened by the aid of rocker arms and
push rods, which gain their timing from a cam placed on the crankshaft.
To save weight in construction the crankshaft, connecting rods, pistons
and cylinders were made of telescopic tubing with a side wall of one
thirty-second of an inch or less in thickness.
The engine has a swing of 5¹⁄₂″ over all, weighs a little less than 8
ounces complete, and is operated on 1,500 pounds pressure (carbonic
gas) and at a speed of 3,500 to 3,700 r.p.m. will develop about 1 horse
power. While spinning a 17″ propeller with a pitch of 20 inches it will
deliver a thrust of 21 ounces, and has a duration of 40 seconds. Two
hundred and fifty-six pieces were embodied in its construction.
[Illustration: The Rompel six-cylinder carbonic gas engine]
THE FORMATION OF MODEL CLUBS
To form a model aëroplane club at least six interested persons are
necessary. As soon as a place in which to hold meetings has been
decided upon the club should proceed to elect a director whose duty
should be to manage the affairs of the club. One of the first things
to be considered is the name under which the club will operate; the
custom is usually to adopt the name of the town or city in which the
club is located, viz.: Concord Model Aëro Club, Concord, Massachusetts,
although it is the privilege of the majority of the members to choose
a name such as they might feel will best benefit the purpose for which
the club was organized. As in the case of the Aëro Science Club of
America, this club was formed for the purpose of stimulating interest
in model aëronautics and to help those who might become interested
therein, not only in New York City but throughout the entire United
States.
When the matter of name and place has been settled the club should
decide upon the course it is to follow, first by electing OFFICERS and
second by preparing a CONSTITUTION AND BY-LAWS. In the case of clubs
whose membership does not comprise more than six members, it does not
seem desirable to have more than one officer, namely, a DIRECTOR, who
might perform the duties of a president, treasurer and secretary until
the club has reached a larger membership. In this way the members are
enabled to concentrate upon the construction and flying of models
and to engage in such other activities as to carry out the purpose
for which the club was organized. However, the foregoing is merely a
suggestion on the part of the writer, who by the way is a member of
the Aëro Science Club of America and formerly acted in the capacity of
secretary to that club.
Clubs whose membership totals more than twelve, however, should proceed
to elect a President, Treasurer and Secretary, all of whom must receive
a vote of at least two-thirds of the membership. With clubs of this
size a director is not needed as the affairs of the club are usually
entrusted with the governing officers, the President, Treasurer and
Secretary. In as much as the constitution and by-laws are an important
factor in the affairs of any model club, the governing officers,
before mentioned, should hold a private meeting at the earliest
moment whereat to frame a constitution and set of by-laws embodying
the purposes and policy of the club. When the proposed constitution
and by-laws are completed they should be presented to the members for
approval after which a copy should be given to every member.
The following is a specimen of constitution and by-laws that might be
used by any person or persons desiring to form a Model Aëro Club:
CONSTITUTION AND BY-LAWS OF A MODEL
AËROPLANE CLUB
ARTICLE 1. NAME. The name of this club will be known as The ..........
Model Aëro Club.
PURPOSE. The object of this club shall be to study and increase the
interest in the science of aëronautics in every way possible and to
realize this object, shall construct and fly model aëroplanes, gliders
and man carrying machines.
FURTHER, Contests shall be held for model aëroplanes and prizes awarded
to the winners thereof. And as a further step in the advancement of
this art, meetings, lectures, discussions, debates and exhibitions will
be held.
ARTICLE 2. MEMBERSHIP. Any person may become a member of this club
provided his application receives the unanimous approval of the
majority of members, or is passed upon by the membership committee.
A member may resign his membership by written communication to the
secretary who shall present it to the membership committee to be passed
upon.
ARTICLE 3. OFFICERS. The officers of this organization shall be a
President, Vice-president, Secretary and Treasurer and a board of
governors to consist of said officers. The president and vice-president
shall constitute the executive committee of the board of governors,
with full powers to act for them in the affairs of the club. The
election of officers shall take place at the first meeting held during
the month of .......... of each year and shall hold office for one
year. In the event of a vacancy in the office of the President the
Vice-president or next highest officer present shall preside. Any
other vacancy shall be filled by an officer temporarily appointed by
the President. The President shall preside at all meetings of the
club and of the board of governors, and shall perform such other
duties as usually pertain to that office. The President shall have
full authority to appoint committees or boards as may be necessary to
further the interests of the club.
The Secretary shall keep a record of all meetings of the club, board of
governors and committees and shall use the seal of the club as may be
directed by the executive committee. Further, he shall issue notices
to officers and members of all special meetings and perform such other
duties as may be assigned him by the constitution, by the club or by
the board of governors.
The Treasurer shall have charge of the funds of the club, receive
all moneys, fees, dues, etc.; pay all bills approved by the board of
governors, and preserve all proper vouchers for such disbursements.
RULES FOR CONTESTS
We now come to the matter of contests. As there are many different
types of models so must there be rules to correspond to avoid
misunderstandings, and until the club has reached the stage where
it may decide upon a particular set of rules under which its members
should participate perhaps the following set of rules, applicable to
contests for hand launched models, can be adopted. In so far as there
are different rules for different contests, namely, hand launched, R.
O. G. and R. O. W. and mechanical driven, the following rules are used
only in connection with contests for hand launched models; rules for
other contests follow:
RULES
A contest to be official must have at least five contestants.
Each contestant must abide by the rules of the contest and decision of
the judges.
Each contestant must register his name, age, and address before the
event.
Each contestant must enter and fly models made by himself only.
Trials to start from a given point indicated by the starter of the
trials, and distance to be measured in a straight line from the
starting point to where the model first touches the ground, regardless
of the curves or circles it may have made. Each contestant must have
his models marked with his name and number of his models (1, 2, 3,
etc.), and each model will be entitled to three official trials.
Contestant has the privilege of changing the planes and propellers as
he may see fit, everything to be of his own construction, but only
three frames can be used in any contest. If in the opinion of the board
of judges there are too many entries to give each one nine flights in
the length of time fixed, the judges have the power to change that part
of rule No. 6 to the following:
“Six flights or less, as circumstances may require, will be allowed to
each contestant, which can be made with one model or any one of three
entered; all of his own construction; due notice must be given to each
contestant of the change.”
No trial is considered as official unless the model flies over 100 feet
from the starting point. (The qualifying distance can be changed by
agreement between the club and the starter provided the entrants are
notified.) Should the rubber become detached from the model, or the
propeller drop off during the trial, the trial is counted as official,
provided the model has covered the qualifying distance. No matter what
may happen to the model after it has covered the qualifying distance
the flight is official. Contests should cover a period of three hours,
unless otherwise agreed.
No contestant shall use the model of another contestant, although the
former may have made it himself.
The officials should be: a starter, measurer, judge and scorer; also
three or four guards to keep starting point and course clear. The first
three officials shall, as board of judges, decide all questions and
disputes. A space 25 feet square (with stakes and ropes) should be
measured off for officials and contestants, together with an assistant
for each contestant. All others must be kept out by the guards and a
space kept clear (at least 25 feet) in front of the starting point, so
a contestant will not be impeded in making his trial.
Each official should wear a badge, ribbon or arm band designating his
office, and must be upheld in his duties.
HANDICAPS
At the discretion of the club there may be imposed a handicap for club
events as follows: A contestant in order to win must exceed his last
record with which he won a prize.
COMBINATION AND DURATION EVENTS
First, second and third records to count. Lowest number of points to
win. For example:
A may have 1st in distance and 2nd in duration, 3 total points.
B may have 3rd in distance and 1st in duration, 4 total points.
C may have 2nd in distance and 3rd in duration, 5 total points.
Accordingly A wins.
R. O. G. CONTESTS
(Rising from the Ground)
Models to be set on the ground and allowed to start off without any
effort on the part of the contestant. Models should rise from the
ground before reaching a predetermined mark, no flight to be considered
unless it does so. Contestant may start at any length back from the
mark, but the distance is to be measured only from the mark.
MECHANICALLY DRIVEN MODEL CONTESTS
For duration, or distance, contests for mechanically driven models
might be held under the same ruling that applies to R. O. G. models.
But owing to the many types of engines used in mechanically driven
models, definite rules for the holding of such a contest must be left
to the discretion of the club or contestants.
EVENTS OPEN TO ALL
These events are open to all, with no handicaps to be imposed on either
club members or others.
INTER-CLUB MODEL AËROPLANE TOURNAMENTS
(Prizes to be determined by contesting clubs)
The tournament to consist of five events as follows:
Duration: Models launched from hand.
Distance: Models launched from hand.
Duration: Models launched from ground. R. O. G.
Distance: Models launched from ground. R. O. G.
Duration: Models launched from water. R. O. W.
Dates for inter-club contest should be arranged for at least three
weeks prior to date of first contest, to allow ample time for the
construction of special models and elimination trials.
In event of inclement weather the contest to take place the week
following (each contest following to be set one week ahead), or at any
time that may be determined by a committee appointed by the contesting
clubs.
Each competing club must be represented by a team of three contestants
and one non-competitor, who will act as judge in conjunction with the
judges from the other clubs, and a manager selected by the judges who
will supervise over the entire tournament and issue calls for meetings.
(Substitutes should also be selected for any possible vacancy.)
Meetings of the judges of the competing clubs should be held at some
designated place, at which time dates and general details shall be
arranged, and between events there should be a meeting called, for
general discussion regarding the recent event, receive protests and
suggestions and to announce officially the result of the contest.
The manager shall have control of the various events, assisted by the
judges and they shall decide all disputes that may arise, and act as
scorers and timers, as well.
Each flyer will be allowed but one model and shall be entitled to three
official flights, but he shall be permitted to make any repairs or
replace any broken parts. No contestant shall be privileged to fly a
model not of his own construction. Each event shall close when all the
contestants have made three official flights, or when three hours’ time
has elapsed.
WORLD’S MODEL FLYING RECORDS
(TWIN PROPELLER PUSHER TYPE MODELS)
MONOPLANE
Year 1917. Ward Pease (America), rise off ground, distance
3364 feet.
Year 1916. Thomas Hall (America), hand launched, distance
5537 feet.
Year 1917. Donovan Lathrop (America), hand launched,
duration 5 minutes.
Year 1917. Emil Laird (America), 18 inch type model,
distance 750 feet.
Year 1915. Wallace A. Lauder (America), hand launched,
distance 3537 feet.
Year 1915. Wallace A. Lauder (America), hand launched,
duration 195 seconds.
Year 1914. Fred Watkins (America), rise off ground,
distance 1761 feet.
Year 1914. J. E. Louch (England), rise off ground, duration
169 seconds.
Year 1915. E. C. Cook (America), rise off water, duration
100 seconds.
(TWIN PROPELLER TRACTOR TYPE)
MONOPLANE
Year 1913. Harry Herzog (America), rise off water, duration
28 seconds.
(TWIN PROPELLER PUSHER TYPE)
BIPLANE
Year 1915. A. H. Wheeler (America), rise off ground,
duration 143 seconds.
(SINGLE PROPELLER PUSHER TYPE)
MONOPLANE
Year 1914. J. E. Louch (England), hand launched, duration
95 seconds.
Year 1914. W. E. Evans (England), rise from ground,
distance 870 feet.
Year 1914. J. E. Louch (England), rise from ground,
duration 68 seconds.
Year 1914. L. H. Slatter (England), rise from water,
duration 35 seconds.
(SINGLE PROPELLER TRACTOR TYPE)
MONOPLANE
Year 1915. D. Lathrop (America), hand launched, distance
1039 feet.
Year 1915. D. Lathrop (America), hand launched, duration
240 seconds.
Year 1914. C. D. Dutton (England), rise from ground,
distance 570 feet.
Year 1914. J. E. Louch (England), rise from ground,
duration 94 seconds.
Year 1915. L. Hittle (America), rise from water, duration
116 seconds.
(SINGLE PROPELLER TRACTOR TYPE)
BIPLANE
Year 1915. Laird Hall (American), rise from ground,
duration 76 seconds.
(FLYING BOAT TYPE)
MONOPLANE
Year 1915. Robert La Tour (America), rise from water,
duration 43 seconds.
(FLYING BOAT TYPE)
BIPLANE
Year 1914. C. V. Obst (America), rise from water, duration
27 seconds.
(MECHANICAL DRIVEN MODEL)
Year 1914. D. Stanger (England), rise from ground, duration
51 seconds.
(All British records are quoted from _Flight_)
DICTIONARY OF AËRONAUTICAL TERMS
A
AËRODROME—A tract of land selected for flying purposes.
AËRODYNAMICS—The science of Aviation, literally the study of the
influence of air in motion.
AËROFOIL—A flat or flexed plane which lends support to an
aëroplane.
AËRONAUT—One engaged in navigating the air.
AËRONAUTICS—The science of navigating the air.
AËROPLANE—A heavier than air machine supported by one or more
fixed wings or planes.
AËROSTATICS—The science of aërostation, or of buoyancy caused by
displacement, ballooning.
AËROSTATION—The science of lighter than air or gas-borne machines.
AILERON—The outer edge or tip of a wing, usually adjustable, used
to balance or stabilize.
AIRSHIP—Commonly used to denote both heavier and lighter than air
machines; correctly a dirigible balloon.
ANGLE OF INCIDENCE—The angle of the wing with the line of travel.
AREA—In the case of wings, the extent of surface measured on
both the upper and lower sides. An area of one square foot
comprises the actual surface of two square feet.
ASPECT RATIO—The proportion of the chord to the span of a wing.
For example if the wing has a span of 30 inches and a chord
of 6 inches the
span
aspect ratio will be 5 or —————
chord.
AUTOMATIC STABILITY—Stability secured by fins, the angle of the
wings and similar devices.
AVIATOR—One engaged in Aviation.
AVIATION—The science of heavier than air machines.
ANGLE OF BLADE—The angle of the blade of a propeller to the axis
of the shaft.
B
BALANCER—A plane or other part intended for lateral equilibrium.
BEARING BLOCK—Used in connection with the mounting of propellers
on model aëroplanes. Made from wood and metal.
BRACE—Strip of bamboo or other material used to join together the
frame side members. Also used in joining other parts of a
model.
BIPLANE—An aëroplane or model aëroplane with two wings superposed.
BODY—The main framework supporting the wing or wings and the
machinery.
BANKING—The lateral tilting of an aëroplane when taking a turn.
C
CAMBER—The rise of the curved contour of an arched surface above
the Chord Line.
CENTER OF GRAVITY—The point at which the aëroplane balances.
CENTER OF PRESSURE—The imaginary line beneath the wing at which
the pressure balances.
CHASSIS (CARRIAGE)—The part on which the main body of an
aëroplane or model aëroplane is supported on land or water.
CHORD—The distance between the entering and trailing edges of a
wing.
D
DECK—The main surface of a biplane or multiplane.
DIRECTIONAL CONTROL—The ability to determine the direction of the
flight of an aëroplane.
DIRIGIBLE—A balloon driven by power.
DOPE—A coating for wings.
DOWN WIND—With the wind.
DRIFT—The resistance of the wing to the forward movement.
DIHEDRAL ANGLE—The inclination of the wings to each other usually
bent up from the center in the form of a flat V.
E
ELEVATOR—The plane or wing intended to control the vertical
flight of the machine.
ENGINE—A contrivance for generating driving power.
ENGINE BASE—Main stick used for frame of single stick model.
ENGINEER—One who controls the power, driving the machinery.
ENTERING EDGE _or_ LEADING EDGE—Front edge or edge of the surface
upon which the air impinges.