"Coanda 1910" jet aircraft

The first ever jet airplane, designed build and tested by the brilliant inventor Henri Coanda was presented at the Second Aeronautical Exhibition in Paris in October-November 1910.
Coanda was only 24 years old at that time. 

Type of the aircraft

The aircraft was a jet sesquiplane with two seats and luggage compartment.
It hadno helices for propulsion unit, but it had a jet thruster system using a "turbine" according with the name that Coanda called it in 1910, meaning a centrifugal blower in nowadays terms that works using fluid reaction.

According with France patent
FR416541A Propulseur / application field 30.05.1910, Coanda claimed his propulsion unit like this:
[pag4, 10-20] "Propulsion unit constituted from a leaded turbine that transform the fluid flow output reactions given by the kinetic energy of the system into axial reactions that are paralel driven with the propulsor axis to generates movement of the craft that use the propulsor"

Dimensions

-Wing span: 10,3m

-Chord: 1,75m

-Lengh of the aircraft: 12,5m

-Lift surface: 32m2

-max. wing load (middle): 33kg/m2 (at 65km/h)

-Weight, without pilot: 420kg

Performances

according to the 7th page of the aircraft oficial paper from 1910 (Francaise)

Thrust of the turbine:
220kg at 50HP

according with the diagrams of the 2nd page of the
aircraft oficial paper from 1910 (Francaise)

Evaluated take off speed:50km/h

We accept that the movement power to be written like this: P[W]=F[N]*V[m/s],
having F=thrust and V=aircraft speed
Reffering to Coanda 1910 jet aircraft we may consider that
V=53km/h=14,7m/s and P=0,87*50HP=31755W
Using the formula and data showed above we found that F=2156N=220kgf for the trhust of the jet system, according to the 7th page of the aircraft oficial paper from 1910 (Francaise)

Wooden and steel fuselage during its construction, that was covered with timber plates in the final phase;
You can see the rounded triangular fuselage sections.

Wings

The wings were uneven and removable having thick airfoil shapes tested before, capable to lift 33kg/m2 at a speed of 65km/h. The wings were higher thickness at the middle and thinner at the edges having each of them two steel bars inside covered with wood and timber plates.
The lateral control was employed by the wrapping of the tips of the upper wing using two wires controlled by pedals in the cockpit. 
Henri Coanda consider in his studies that wing is a jet machine producing lift using aerodynamic reaction, a sort of jet wing. Please read his article Sur aille considerees comme machines a reaction _ April1910 (Francaise)

You can see and read the original patents of the initial airfoil shape.
FR416542A Surface portante pour machines volantes / application field 30.05.1910 (Francaise)

The real airfoil shape is diffrent from the patented one from technologic reason, but is similar in its esence.

The real airfoil shape of the wings used at Coanda 1910 jet aircraft was a special one, coming from the birds wings, but specialized to get more lift and lower drag, as Henri Coanda observed during its experiments.

You can see in the left image, the true airfoil shapes during the construction of the 1910 aircraft down wing.

Wings have higher thickness at the middle of the aircraft and lower thickness at the edges that determine a variation of the lift over the wing surface represented in the left diagram, at diffrent speed. The values were experimental determined and possibly even later estimated starting from experimental data.

lift at the middle of the wing located near the main body:
18kg/m2 at speed of 50km/h
33kg/m2 at speed of 65km/h;
42kg/m2 at speed of 80km/h;

Aerodynamics ribs under the leading edge of the wings were present at the first jet aircraft of 1910.;

Tail

In the back of the aircraft there were a St. Andrei cross shape tail and a small horizontal tail used for lifting the back part of the aircraft during the take off procedure at lower speed, necessary to obtain full horizontal thrust.

This small horizontal tail is not indicated in the original patent meaning that was added after the initial experiments.

You can see and read the original patents of the general aircraft.
FR418401A Perfectionnement aux aeroplanes / application field 20.07.1910 (Francaise)

Landing system

Landing system with two retractable wheels and two sleds,  one sled placed in front to prevent nose-over and one sled at the back to support the tail on the ground.

The landing sistem is also different from the same system indicated in the original patent.

You can see and read the original patents of the general aircraft.
FR418401A Perfectionnement aux aeroplanes / application field 20.07.1910 (Francaise)

Stability and control

Gravity center was placed closer to the upper wing for better maneuverability.

Longitudinal stability achieved by a Saint Andrei cross shape tail for vertical and horizontal movements.

Two separate wheel to drive the Saint Andrei cross shape tail for control the direction of the aircraft

You can see and read the original patents of the tail control sistem
FR418401A Perfectionnement aux aeroplanes / application field 20.07.1910 (Francaise)
DE264493C / application field 30.05.1911 (Deutsch )

extras from DUDKO drawing, made after Coanda specifications back in '50

Jet propulsion system

The propeller generated thrust by using reaction inside the "turbine", as named it Henri Coanda back in 1910, a centrifugal blower jet thrust in accordance with the today definition.

You can see and read the original patents of the propeller (the texts are different)
FR416541A Propulseur / application field 30.05.1910 (Francaise)
FR13502 of FR416541A Propulseur/ application field 03.12. 1910 (Francaise)
CH58323A Propulseur / application field 26.05.1911 (Francaise)
GB191112740A Improvements in or relating to Propellers/ 30.05.1911 (English)
US1104963A Propeller / 29.05.1911 (English)

The "turbo propeller" meaning the 1910 jet system was made from:

= 50HP CLERGET type 4V, 4 times stroke, 4 pistons+
+gear system for rising the rotational speed up to 4000rpm+
+metal (Al) centrifugal blower in two known variants+
+injectors and burners in according with Coanda said back in '50

Clerget 4V 50HP engine

Clerget 4v 50HP engine

-4 stroke engine
-4 cyl in line
-water cooled

-aluminium pistons
(after Gerard Hertmann)
-bore 110 mm,
-stroke 120 mm
-CU : 4560 cm3

-weight: 78kg complete
(after its presentation brochure)
-weight :99kg
(after Gerard Hertmann) ,

-price: 10000 FR (1910)
(after its presentation brochure)

Detail of one of the two radiators of the water cooling system. 

The radiators were placed on the left and right sides of the cockpit of the Coanda 1910 jet aircraft

Clerget 4V 50HP engine
and
Clerget 4W 110HP engine
shown in their presentation.

Clerget 4V 50HP

-built at Malicet & Blin works, Aubervilliers, France
-production : 35 units.
(after Gerard Hertmann)

image source is http://www.loc.gov/rr/scitech/trs/hanriot1911.html

image from http://www.enginehistory.org/technical_museum.htm

A similar 1909 Clerget4V engine is now exhibited at the Technical Museum in Vienna according with Aircraft Engine Historical Society - AEHS

More information about this engine are welcome! (drawings, pictures, technical date, history)
Thank you!

Gear system for rising rotational speed up to 4 times

A 4 times rising gear for rotational speed is shown in the
FR416541A Propulseur / application field 30.05.1910 (Francaise)
CH58323A Propulseur / application field 26.05.1911 (Francaise)
GB191112740A Improvements in or relating to Propellers/ 30.05.1911 (English)
US1104963A Propeller / 29.05.1911 (English)

If the Clerget 4V rpm data are correct recorded and after we consider the patent gear ratio at 4 times rising the Clerget 4V engine rpm, we can easyly obtain 6000-8000rpm for the turbine. Anyway, the initial patent gear ratio of a 4 times rising rpm could been modified during the tests in order to got down or up to 4 times.

Metal (Al) centrifugal blower in two known variants

The aluminium rotor of the Coanda 1910 jet aircraft was made for speed up air in a centrifugal blower way for up to 4000 rpm and it was seated in a conical metal shape.

The turbine (centrifugal blower) is shown in the
FR416541A Propulseur / 30.05.1910 (Francaise)
CH58323A Propulseur / 26.05.1911 (Francaise)
GB191112740A Improvements in or relating to Propellers/ 30.05.1911 (English)
US1104963A Propeller / 29.05.1911 (English)

We have to admit that the real turbine is diferent than the turbine showed in the initial patent as we can see in the left:


The other views of the turbine (centrifugal blower) are shown below:

A static air driving metal (Al) device with 15 curved shape blades fixed together was locate before the rotor for directing towards it the air flow in the right way.

The rotor and the stator both partially assembled were looking like views below.

The second later design of the turbine (rotor, centrifugal blower) of the 1910 jet thruster

FR13502 of FR416541A Propulseur/ application field 03.12. 1910 (Francaise)
CH58323A Propulseur / application field 26.05.1911 (Francaise)

There were manny changes made of the jet thruster system that appeared during the tests of the 1910 jet aircraft.

Henri Ccoanda explains the reason of it inside the patent
FR13502 of FR416541A Propulseur/ application field 03.12. 1910 (Francaise)

[page 2 45-55] "This addition to the main patent relates to improvements concerning the jet thrust system already done, for increasing its efficiency [...] that will no longer generates noise and unwelcome vibrations lowering the performances."

Injectors and burners according with Coanda

According with Coanda says after the World War II the 1910 thruster had also after the turbine (rotor) a burner with two "reactive tubes" positioned in "both parts" of the wooden fuselage.
In these tubes was probably placed a burning process capable to generate two "powerful flames"
that produces a "temperature that feels too much", enough to determine the young pilot (Henri Coanda) to stop the tests and cover up and down these flames using two mica plates".
It seems the to be the main cause of taking fire of the whole aircraft when the tests were reloaded and the aircraft had crashed.

It is obvius that at the time of the first patents in May 1910, Henri Coanoda didn't intend to burn any fuel inside its jet propeller because of his very good evaluation of the thrust using only air, but later on during the jet aircraft tests he observed that the jet propeller had less thrust than he estimated and try to rise up the efficiency of the jet system. The addition of the first propeller patent make this clear in FR13502 of FR416541A Propulseur/ application field 03.12. 1910 (Francaise). The second design of the turbine had more efficiency then the first one, but if it was insuficient, it is clearly that Henri Coanda pressed by the time tried to resolv the problem in another manner that can include a new addition of the energy into the system by using hot gases that might comes from an extra burning device, like the one that he talked about later in the '50 years.
Based on our observations about Coanda way of thinking and creations during the time, we have reasons to believe that during May and December 1910, Coanda 1910 jet aircraft had undertaken many updates which had never been patented. Please help us to discover them! Thank you !

Perce Neige (Snowdrop, Ghiocel)- Coanda 1910 Sleigh

The same propulsion sistem, but without any additional burner was part of Coanda sleigh in December 1910
The sleigh was build for the Great Duke Cyril of Russia in Dec 1910 according with Popular Mechanics, March 1911, pag 359.

The sleigh was baptized by priest of the the Russian Church according with the 3rd page of the Le Temp / 03dec1910, Le bapteme d'un traineau automobile.
The sleigh name was Perce Neige in French or Snowdrop in English or Ghiocelul in Romanian.

One of the daily invitation to visit the Coanda-Gregoire sleigh exposed at the Car Exhibition in December 1910 at Paris.
Le Temp / 14dec1910, Au salon de l'automobile

The announce made in the 3rd page of the Le Temp / 19dec1910, about the final day of the Cars Exhibition in Paris

Sleigh perfomances

- power by the a single Gregoire engine:
40HP Popular Mechanics, March 1911, pag 359.
30HP.....

- estimated speed
50mph (80km/h) Popular Mechanics, March 1911, pag 359.

The Snowdrop, Coanda 1910 jet sleigh, might be now in Russia.
Any information about this sleigh are welcome!
Thank you!

last update 05-Sep-2016