Captain Ferdinand Ferber
References are to Le Matin, except where otherwise shown
1904-08
Lucien Marchis et al, Vingt-cinq ans
d’Aéronautique française, 2 vols., Chambre Syndicale des Industries
Aéronautiques, Paris 1934.
pp. 21-24
One of Ferber’s findings, from his experiments with a whirling arm at
Nice, and then with an aircraft sliding down an inclined cable at
Chalais-Meudon in 1904, was that whereas a boat or car moving on one surface
needs only one steering control [gouvernail], a machine moving in three
dimensions must have three. These are a rudder for steering, one for
‘profondeur’ [i.e. an elevator], and a ‘gouvernail’ to give more or less
‘bande’. [This presumably refers to roll.]
Ferber’s aircraft No. 8, built at
Chalais-Meudon [in 1905?] and fitted with a specially ordered 24 hp Levavasseur
motor driving two propellers – but then destroyed before trial by bad weather
after being left in the open air – was rebuilt in the same form in 1908 as the
Ferber No. 9. Ferber was still seconded to Levavasseur. The machine flew well
in July 1908 (as it would have done in 1905).
………………………….
1907
January 1907, L’Aérophile 15:1, January 1907
pp. 30-31 Ferdinand Ferber: ‘De la rapidité
avec laquelle las aviateurs s’orientent vers l’avenir’ [‘On the rapidity with
which aviators orient themselves towards the future’]
Ferber says he has shown mathematically
that to double the speed of an aircraft a) power must be increased 8 times b)
the angle of attack [‘angle d’attaque’] must be reduced by a half c) surface
area must be divided by four d) some
combination of the above must be used.
a)
Is hard and expensive, though
Santos-Dumont has gone from 50 hp to 100 hp
b)
Reducing the angle of attack by
half is also hard since it means reducing the damaging [‘nuisible’] surface
which resists advance to a quarter of its value, and building an aeroplane that
is very fine [‘très fin’] in the sense used in the marine for this word
[‘streamlined’ or ‘smoothly finished’?]. Santos-Dumont, for that purpose,
builds his surface with varnished mahogany, and Blériot is abandoning double
surfaces that offer too much resistance. [Meaning? Turning to monoplanes?]
c)
Reducing the loaded surface by
four is easy. Santos-Dumont and Blériot have tried this. But Ferber thinks it
is risky, since it will raise the speed needed for take-off. Ferber and
Santos-Dumont have found that a 300 kg aircraft, of area of 50 square metres,
has a normal speed [‘vitesse de régime’] of 10 metres/second; while an aircraft
of 300 kg of 13 square metres area will have a speed of 72 kph – a high speed
to be reached on the ground, for take-off. Ferber thinks that Santos-Dumont and
Blériot, using 50 and 24 hp respectively, could not reach these speeds using
propellers in direct drive. They possibly could if the propellers were geared
down [‘démultipliés’], as is shown in Ferber’s theory of propellers (sent to
the Académie and visible in its comptes rendus of 21 January 1907). At 100 hp
Santos-Dumont would have excessive power. In the aircraft that Ferber is now
building, in collaboration with Levavasseur (the inventor of the light motor),
the surface area is divided by two (to 25 square metres), giving an estimated
normal speed of 60 kph.
Stability:
Santos-Dumont has made a complete reversal of his previous position [in,
apparently, abandoning his pusher canard of autumn 1906]. This is logical. He
now conforms with nature, and his aircraft will now be stable (though the many
who have ordered aircraft like the 14bis will suffer). Santos-Dumont flew because
he had power, not design. ‘It must be clearly understood that the solution of
the problem is today in anyone’s hands; that all surfaces will fly – it is only
necessary to push them.’ On stability,
Santos-Dumont’s current plans are excellent. (The aircraft is sketched here: it
is a biplane of 11 metres span, a very high aspect ratio, high dihedral,
tractor propeller, a 3 metre tailplane, a vertical tail, and ailerons
projecting forward from the wing. Airflow [l’écoulement de l’air’] is carefully
respected.)
Given the lack
of a hydrodynamic theory of fluids (which still does not exist because the
integration of the equations is too hard), Ferber likes the following image for
the balance of an airplane:
‘Imagine the
aeroplane in a current of air at its normal speed [‘vitesse de régime’], then
solidify this air in your thought, extract the aeroplane, and look. If you see
a good seal, well hollowed and deep, with well rounded, not jagged, edges, you
are in the presence of a stable aeroplane.’ [The meaning here is unclear]
Doing this with
the Blériot plane shows it is clearly stable. This is the Blériot 6, a canard
monoplane with semi-circular wing, a pusher propeller driven by a 24 hp
Antoinette motor, (or 50 hp before downgearing), weighing 260 kg, and with a wing area of 13
square metres.
On strength:
Ferber has always felt that a monoplane, being so little braced, lacks strength
for landing. Therefore he has always built on the Hargrave plan, which gives
properties of a reinforced girder. Nonetheless Ferber now yields to his
colleague Levavasseur – the landing does not really matter if the journey goes
well.
There is
reference here – planform on p. 30 – to Ferber and Levavasseur’s Antoinette 1.
It is two place machine, designed by them in collaboration, of 25 square metre
area, weighing 500 kg, and fitted with a 100 hp Antoinette motor. It is a
pusher monoplane with the propeller at the tail, the engine amidships, a rear
vertical rudder, triangular tailplane, and canard elevator. The wing has high,
but curving, dihedral (i.e.more dihedral at the roots, less at the tips).
[The frequency
of French references to Hargrave and his type of aircraft is notable]
Blériot uses two
wheels. Santos-Dumont and Levavasseur/Ferber use only one. It must be
remembered that the Wrights on 17 December 1903, used only one wheel. [This
reference to the Wrights is interesting. Ferber seems to be acknowledging their
flights of 17 December 1903. On the other hand, he is wrong about the wheel.
The Wrights on that day, and later, used no wheels. Their aircraft rolled on a
dolley along a wooden rail, and landed on skids.]
This single
wheel arrangement seems at first sight extraordinary. But recall that the
aircraft must move without jolting [‘sans secousse’] from ground to air. In the
air, air resistance equals the pull of the motor and the total weight.
So that there is
no discontinuity on take off, ‘the reaction of the ground must be arranged in
such a way that it is unique and can balance the pull of the motor with the
total weight’ [‘… il faut organizer la réaction du sol, de manière qu’elle soit
unique et puisse équilibrer la traction du moteur avec le poids total’] [The
meaning of this is obscure, but may have to do with concentrating the weight of
the aircraft – i.e. the centre of gravity – over the wheel.] Thus it is
necessary to use only one wheel, placed directly beneath the point where air
resistance is applied [‘placée à l’aplomb de l’endroit où s’appliquera la
résistance de l’air’]. The pilot [‘conducteur’] will doubtless find surprises
in this to begin with, but as control movements to balance the aircraft on the
ground will be the same as those used in the air, if he cannot control on the
ground he will not be able to do so in the air either.
‘However it may
be, what precedes show that 1907 will be rich in lessons.’ [‘Quoi qu’il soit, ce qui précède montre que
l’année 1907 sera fertile en enseignements’.] [Which indeed it was.]
[The above suggests:
1.
The French monoplane tradition
takes off in 1907 (though it should be recalled that Ader in the 1890s and
Esnault-Pelterie after 1900 had tried monoplanes).
2.
There are no clear appeals here
to the Wright brothers’ trials, though Ferber seems to accept that they had
flown in December 1903. He thought that the Wright aircraft had a wheel, which
it did not.
3.
There is reference here (as by
others at the time) to Hargrave’s biplane layout – but none to Chanute or to
Langley.]
[This piece
shows Ferber feeling towards a sure knowledge of the mechanics of flight. But
he still lacking some elements of the calculation. For instance, his assertion
that doubling an aircraft’s speed requires an eight-times increase in power
takes no notice of drag (except that reducing wing area – which he suggests -- would cut drag). If drag is reduced, the required increase in
power also falls. Some parts of his
argument are hard to follow. But here in January 1907 he is drawing on very
little success in France in flight. Santos-Dumont has flown in late 1906, and
hence figures largely in the article. Blériot is also mentioned, though he has
not yet flown successfully. But these are the only current French aviators that
Ferber has to draw on.]
………………………………………
11 November, p.5.
Ferber is to give a lecture at 9.30 this
evening at 11 Rue Servandoni [Paris], place St. Sulpice, on aviation and its
current development. This is under the auspices of the Société de Elèves
Industriels de France.
…………………………..
1908
18 January, p.6.
Ferber was one of some forty builders interested
in aeronautics who met yesterday at the Automobile Club de France to consider
the foundation of a Chambre Syndicale des Industries Aéronautiques.
…………………………..
25 January, p.5.
Ferber attended a dinner on 23 January for
some 200 people to celebrate the ten years of the AéroClub de France.
………………………….
30 January, p.4.
The founding assembly of the Chambre
Syndicale de l’Industrie Aéronautique took place yesterday. Statutes were adopted
and a committee formed, of which Captain Ferber is a member.
………………………….
26 July, p.6.
Ferber – ‘who astonished with his deep
knowledge as an airplane pilot’ – yesterday made several very interesting
flights at Issy. He said that his aircraft was the same as the one tried out in
19[04?] at a time when he no longer had a light motor. It is [says Ferber]
simple: a wing cell whose extremity can be twisted by means of a lever – ‘that
is to say, to take on a more or less accentuated angle of incidence’ – together
with an elevator (’gouverneur de profondeur’) in the nose and a fixed empennage
in the tail.
‘Steering is operated by means of ailerons
placed to the right and left of the wing cell; but I think I will go back to
the rudder (“gouvernail“).’
[So it seems that this aircraft has a fixed
rudder (thus operating as a fin), steering with ailerons placed somewhere
between the wings, and warping (presumably) to level the wings.]
[Here, it seems, ailerons are being used to
cause a turn, although Ferber is considering going back to a rudder for that
purpose.]
………………………..
17 August, p.5.
Ferber is in the final days of leave. He
has made a trial of his biplane aircraft (on 15-16 August), flying about one
kilometer, with a turn. He has been recalled to active service at Brest. He has
given his aircraft, the Ferber 9, to a young mechanic, Legagneux, whose energy
and courage he noticed in these recent trials.
………………………….
18 August, p.5.
Yesterday Ferber gave Legagneux, his pupil,
flying lessons. Several short flights were completed.
…………………………
19 August, p.5.
Legagneux flew at 5 a.m. on 18 August, for
about 400 metres.
…………………………
20 August, p.2.
The four-to-six [a.m. schedule] at
Issy-les-Moulineaux was marked yesterday by success, as Legagneux took the
third and last bonus [‘prime’] for 200 metres offered by the AéroClub de
France, flying the Ferber 9. Taking off from the Porte de Sèvres, Legagneux
flew 256 metres in 23.6 seconds, witnessed by the AéroClub commissaries
Demanest and Fournier, assisted by Ferber. Legagneux stopped only because he
feared to hit a shack near the railway line. Shortly after his win, he flew
back, making a 300 metre circle to the hangar.
………………………..
1909
15 March, L’Aérophile
p. 122.
An article by Captain Ferber (described as the Commandant of L’Ecole des
pilotes de la Ligue Nationale Aérienne) on the question of creating a
successful full-size aircraft from the basis of a model. Many are now
frustrated that the successful model does not translate into a successful
full-scale aircraft.
The basic point made is that the weight of
full-size aircraft increases as the cube of the original, as volumes increase
by a cubed amount, and the density of materials stays the same.
Two principal equations apply to an
aircraft.
The first gives the thrust required vs the
weight (in kilograms):
F = 2Py – where y = the angle of attack
expressed in ‘parts of the radius’ [‘parties du rayon’].
So, if the size of the aircraft increases x
times (i.e. if the dimensions are increased thus), the equation becomes Fi = 2Pyx cubed [i.e. the x is cubed]
If 2Py is substituted for F
Fi = x cubed F. Thus the thrust needed is x
cubed greater than in the model.
2. gives speed in meters/second: K S Vsquared y = P
Where K = coefficient of resistance of the
air (0.3 for models), S = lifting surface in square metres, [and P presumably =
weight].
For an aircraft expanded x times, Pi = x
cubed, P Si = x squared S
Yi = y (angle of attack), and K is
constant. Thus Vi = V times the square
root of x.
Thus the speed on the second aircraft will
only be root x times greater; while the work in kilogrammètres needed, in the first case FV, becomes in the second
case FV x cubed – i.e. x cubed times root x larger.
For the thrust of a propeller, using
Renard’s formula: F = a (n squared) (d
to the fourth) (where n = revolutions per second, d = diameter, and a is a
coefficient). On a second, larger, aircraft, Fi = F x cubed, di = dx. Hence ni
= n divided by square root of x to the
fourth. Thus revolutions per second must
be divided by the square root of x to the seventh if proportionality is to be
conserved.
Because these proportions are not generally
observed, full sized aircraft based on models generally do not work. These
formulae show how quickly necessary force grows. This explains why, for each
epoch of aircraft, given a finesse of
construction and a specific lightness of motors, there is a speed limit. In
effect it is pointless to increase size because a point comes where the
aircraft is completely filled by the engine.
[This is Ferber’s mathematical reasoning of
the relationship in aircraft between size, weight, thrust, and speed. It has
not been possible to write the equations in algebraic notation. Clearly his
final conclusion is wrong: aircraft can, and did, become larger without being
completely filled by their engines. But it is interesting to see a mathematician
tackling design problems at this time in France.]
………………………………………
15 May, L’Aérophile
p.218 F. Ferber, ‘L’Aviation et les Spectacles’
Ferber criticizes entrepreneurs who put on
public spectacles. They see flight as a paying entertainment, and demand that
pilots fly in any weather, from any field, at any specified time, however
unsuitable or dangerous. Aviators find themselves subject to moral pressure,
and take risks – for example, Delagrange in Rome, Henry Farman in New York,
Zipfel in Berlin, and now Legagneux in Vienna.
The greater the reputation of the flier,
the easier the pressure is to resist.
Legagneux started flying with Ferber last
August, on Ferber’s aircraft. Then, at Châlons, he did only a few taxi-ing
circles with Farman. He has been obliged to fly in Vienna over a space full of
holes, ditches, etc. It is an area sometimes flooded by the Danube.
According to the Neue Freie Presse of 24 August Legagneux made four or five
unsuccessful attempts to fly. The gentlemen of the Syndicate grew impatient,
and talked of having Farman come. Then Legagneux changed the angle of the tail
and flew 1,500 metres in circles at 8-10 metres height. But he said afterwards
that if it had not been said that he lacked courage, he would not have flown
because of the risk of breaking the aircraft. Since then Legagneux has been
forced to fly in wind, and the aircraft has suffered serious damage to its
engine, propeller, etc.. It is to be hoped that the Syndicate will learn from
this. The irony is that Legagneux, an experienced pilot with Antoinette, has an
English marquis and an Austrian engineer as his mechanics.
There are similar problems with towns that
wish to offer entertainment [‘jeux’] to their people. Prizes are announced, but
no account is taken of the terrain, day, and time.
Wilbur Wright behaved well at Pau. He
announced that flying trials would take place when the aviator concerned
decided to fly. His principle was to invite nobody, but to charge entry. At
Pau, where Wright did not fly, not even a rain check [‘contremarque’] was
given. Nobody complained; but receipts were high.
…………………………………
…………………………………
Bibliothèque d’Etude et du Patrimoine,
Toulouse.
General Charles Christienne, L’Aviation Française 1890-1919. Un certain
âge d’or, Paris, 1988
p. 40
Ferber, though a polytechnicien, especially good at mathematics, was not a savant like Charles Renard; and though
he was imaginative, he lacked the inventive genius of Ader. He is best
described as ‘a scientist, a practitioner, a communicator’.
42. Ferber read German. When he was posted
to Fontainebleau, to the army’s ‘école d’application’ in 1896, he found an
article on Lilienthal in the Illustrierte
Zeitung. Lilienthal’s work was little known in France. This began his
interest in aviation. He later wrote: ‘my only merit has consisted of seeing
the question clearly, and of considering how one should take up Lilienthal’s
experiments, so that France should profit from the movement that should develop
from that’.
43. He observed soaring birds, and then
tried to explain in mathematics what he saw. He also said: ‘to build a flying
machine is nothing, to build it is little, trying it is everything’. [Perhaps
true, so long as the building was good – which, in the case of Ferber’s copies
of Wright gliders, it was not.]
Ferber also saw that collaboration was
needed for the advance of flight. (Contrast Ader and Renard, for whom secrecy
was central because of the military potential of flight.) Ferber tried contacting
Ader, after 1897, but Ader, wounded by his failures, which he attributed to the
minister of war, did not collaborate with him.
46. In November 1901 Ferber wrote to
Chanute, who replied mentioning the Wrights’ work, and his own written work.
Ferber later replied to critics who said
that he should keep his aviation work secret: ‘Ideas do not belong to a man,
but to a time. It is important therefore, for the cause of aviation, to thrust
onto this idea as many people as possible’. [The author notes that in 1900 the
Wrights had the same idea – that multiple contributions were needed for the
success of heavier than air flight. They soon changed their minds.]
48. Ferber preferred monoplanes for
aesthetic reasons, but chose to use biplanes because (he said)
1. The same weight of structure gives twice
the surface area [of the wings, presumably]
2. The construction method of ‘triangular
lattices’ [‘réseaux triangulaires’] gives the framework very great solidity.
[Here he was perhaps referring to diagonal wiring between the wings.]
3. The mathematics of biplane structure is
known. It is the same as that of a building a bridge.
On his No. 6 Ferber had contra-rotating
propellers on the same shaft – this was in 1905.
50. Ferber’s potentially brilliant military
career was blocked [according to the author] by small mindedness and stupidity
[in the army. It is not clear what happened, except that his aircraft No. 8, at
Meudon, was moved outside from an airship hangar, and wrecked in a storm.]
To the end, Ferber continued to be a
marvelous propagandist for heavier than air flight, working with Archdeacon,
Voisin, Levavasseur and others.
58. In November
1907 Archdeacon, in a speech before the AéroClub de France honouring French
aviators, publicly expressed doubts about the Wrights’ achievements, saying
that he doubted increasingly that they were the first to fly. To show that they
were, they should have done trials openly, before official witnesses, like the
French pilots. But Ferber, in a letter to G. Besançon, said that without Wilbur
Wright he would not have dared in 1902 to try to fly (on a ‘feeble piece of
cloth’ [‘une faible toile’]). It was reports and photographs of the Wrights
that persuaded him to try. If he – Ferber – had not done that, he would not
have had Gustave Voisin as a pupil, Archdeacon and Deutsch de la Meurthe would
not have in 1904 created prizes, the press would not have spread the ‘good seed’,
the journal L‘Aérophile would not
have increased its circulation four times, and other journals would not have
started. ‘Without our press campaign in 1905 … the most secure news from
America would not have come to France, and our country would not have become
the sole market for aeroplanes – although Wright had to come here to sell his
invention…’
59. [The author
notes that Ferber had had the idea of flying before he heard of the Wrights.]
………………………………
………………………………
Ferdinand Ferber
was an intriguing character. He was always present in the years of development
of French aviation after 1900, and played a key role as an exchange point of
information -- between Frenchmen and between America and French aviators. He
relayed information provided by Octave Chanute about flight in the USA to the
French developers of airplanes after 1900.
He had some direct contact with the Wright brothers. His mathematical
contributions to aircraft development do not seem to have led to any useful
advances. They certainly did not lead to his building any impressive airplanes.
The impression he gives is of not having been a very practical man. His
attempts to make copies of Wright airplanes were failures because, in good
part, of bad construction. Later – after 1906 – he was never among the leaders
in flying, although he did fly, and was a source of encouragement and support
to those who wanted to do so.
In September of
1909 he took part in a flying meeting at Boulogne-sur-Mer in northern France.
He flew a Voisin biplane. In that aircraft he suffered a landing accident when
the aircraft rolled into a drainage ditch that was covered over in grass. The
aircraft pitched down; the motor broke loose, and fell onto Ferber. He died
soon after from the resulting internal haemorrhage.
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