Association of Ex Aviation Construction of the Argo 02. Strength calculation of the spar. Catering and provision of additional services
Is it possible in our time, which is called the period of total shortage, to build an airplane on its own? Tver amateur aviators Yevgeny Ignatiev, Yuri Gulakov and Alexander Abramov answered this question in the affirmative, creating a winged one-seater aircraft, later named "Argo-02".
The aircraft turned out to be successful: it successfully flew at the All-Union ALS competitions in 1987 and 1989, was the first prize-winner of the regional review-competition of amateur aircraft in Yaroslavl. It aroused increased interest among amateur aircraft designers - both the Argo developers and the editorial staff of the Modelist-Constructor magazine received many letters with requests to tell more about this aircraft on the pages of MK.
The secret of the increased popularity of "Argo" is not in the design or technological sophistication of the designers, but rather in the traditional design and technological methods used to create the aircraft. The developers managed to achieve a successful combination of the techniques for designing wooden machines of the 1920s and 1930s, worked out over many decades, and modern aerodynamic ideas about aircraft of this class. This, perhaps, is one of the main advantages of the aircraft: modern plastics and composites, rolled products from high-strength metals and synthetic fabrics are not required at all for its manufacture - only pine timber, a little plywood, linen and enamel are needed.
The Argo is an airplane with a single-spar wing: its frame consists of a box-shaped spar and a set of pine truss ribs. The wing skin is made of linen, and only the wing tip, which receives the torque, is sheathed with plywood. The fuselage is a pine truss with the same linen sheathing in the rear and plywood in the bow. The plumage is a light openwork tray truss covered with canvas. The chassis is quite modern design - it is a fairly simple steel spring. The engine was originally a four-stroke engine from a heavy Ural motorcycle, then a lighter two-stroke RMZ-640 equipped with a gearbox. Such a motor, even today, can still be "obtained" in the store.
However, the simplest construction of the simplest materials is just one of the components of the success of the machine. In order for all these pine slats and pieces of plywood to fly in, they must be "fit" into well-defined aerodynamic shapes. In this case, the authors of "Argo" - we must pay tribute to them - have shown an enviable design wisdom. For their aircraft, they chose the aerodynamic design of a classic cantilever monoplane with a low wing and a pulling propeller. Nowadays, against the background of a wide variety of "ducks", "tandems" and other wonders of modern aerodynamics - the plane of the "Argo" looks even conservative. But this is precisely the design wisdom: if you want to build an original plane, do the duck, but if you want to build a flying plane, choose the classic scheme: it will never let you down.
However, this is not all. For an aircraft to fly well, it is necessary to correctly determine the ratio of its mass, engine power and wing area. It is difficult to say whether the authors were helped by an accurate calculation, design intuition or a good knowledge of the statistical data of such aircraft, but the parameters of the "Argo" can be considered optimal for an apparatus with an engine power of 28 liters. with. The parameters of the "Argo" can be taken as a sample if someone wants to build such an aircraft. It is these ratios of parameters that provide the best flight performance characteristics: speed, rate of climb, takeoff run, mileage, etc.
At the same time, stability and controllability are determined by the ratio of the area of the wing, empennage and rudders, as well as their relative position. And in this area, as it turned out (which the designers of the Argo understood perfectly well!), No one has yet invented anything better than the standard classical scheme, and on the Argo the parameters are taken directly from the textbook: the area of the horizontal tail is 20% of the wing area , and vertical - 10%, the empennage shoulder is 2.5 of the aerodynamic chord of the wing, and so on, without any deviations from the classical design rules, which obviously makes no sense to deviate from.
The aerodynamic data of the aircraft even made it possible to perform aerobatics on it. But aerobatics is not only good aerodynamics, but also high structural strength. According to the calculations of the authors and the technical commission, "Argo" could withstand an operational overload of no more than 3, which is quite enough for flights in a circle and on short routes without complex evolution in the air. In short, aerobatics was categorically contraindicated for this aircraft.
But, apparently, successful and calm flights "pancake on the horizon" soon bored the authors-pilots of "Argo". The fact that the strength of the aircraft is insufficient for aerobatics was forgotten. Bends were replaced by deep bends, then barrels, coups ... On August 18, 1990, when performing an exhibition flight at a festival, dedicated to the Air Fleet, Yuri Gulakov led the Argo into another coup. This time, the speed was slightly higher than usual, and the maximum operational overload, obviously, was much higher than the calculated "three". As a result, the wing of the "Argo" collapsed in the air, and the pilot died in front of the assembled spectators.
Here one could "read the moral" about the need to comply with flight rules, flight discipline and other important things. However, experience shows that such instructions are not useful until the pilot himself understands that there is no place for discipline in aviation. It's a shame that sometimes it comes too late.
As a rule, such tragic cases, even with all the obviousness of the reasons that cause them, force us to look for errors in the design and in the calculations of the aircraft. However, in relation to the design of the Argo-02 aircraft, this is not required: the aircraft withstood exactly what it was designed for.
That is why the technical and flight methodological commissions for aircraft amateur construction The Ministry of Aviation Industry of the USSR recommends the aircraft "Argo-02" as a prototype for self-construction in amateur conditions.
V. KONDRATIEV,
vice-chairman
technical and flight-methodical commissions
Ministry of Aviation Industry of the USSR
AIRCRAFT FLIGHT DATA
- Length, m ........ 4.55
- Height, m ........ 1.8
- Wingspan, m ..... 6.3
- Wing area, m 2 .... 6.3
- Wing constriction ...... 0
- Terminal chord of the wing, m ... 1.0 MAR, m ......... 1.0
- Angle of installation of the wing, deg. ... ... 4
- Angle V, deg. ....... 4
- Sweep angle, deg. ... ... 0
- Wing profile. ... P-III — 15.5%
- Aileron area, m 2. ... ... 0.375
- The scope of the aileron, m. ... ... ... 1.5
- Angles of deflection of the aileron, deg .:
- ..up ........ 25
- .. down ........ 16
- The scope of the GO, m. ... ... ,. 1.86
- GO area, m 2 ...... 1.2
- Installation angle of HE, deg. ... 0
- RV area, m 2. ... ... ... ... 0.642
- VO area, m 2 ..... 0.66
- VO height, m. ...... 1.0
- RN area, m 2. ... ... ... ... 0.38
- RN deflection angle, deg. ... ± 25
- RV deflection angle, deg. , ± 25
- The width of the fuselage in the cockpit, m. ... ... 0.55
- Height of the fuselage in the cockpit, m ...... 0.85
- Wheel chassis base, m. ... 2.9 Track of the chassis, m ...... 1.3
Power point- RMZ-640 engine with a silencer, air cooling
- Power, l. with. ...... 28
- Max, rotation frequency,
- 1 / min ........ 5500
- Reducer. ... ... V-belt, four-strand, belts A-710
- Gear ratio .... 0.5
- Fuel ..... gasoline A-76
- Oil ........ MS-20
- Screw diameter, m. ... ... ... 1.5
- Screw pitch, m ...... 0.95
- Static thrust, kgf .... 95
Empty weight, kg ... 145
- Maximum takeoff weight, kg. ... ... ... ... ... ... ... 235
- Fuel capacity, l ...... 15
- Range of flight balance, MAR ........ 24 ... 27
- Stall speed, km / h. ... 72
- Max, level flight speed, km / h ..... 160
- Max, piloting speed, km / h ......... 190
- Cruising speed, km / h ... 120
- Tear-off speed, km / h ... 80
- Landing speed, km / h. ... 70
- Rate of climb at the ground, m / s .......... 2
- Takeoff run, m ........ 100
- Mileage, m ........ 80
- Range of operational overloads. ...... + З ...- 1,5
- Dimensions during transportation, m ....... 5X2,3X1,8
CONSTRUCTION, TECHNOLOGY, CALCULATIONS
"Argo-02" is an ultralight training cantilever monoplane of a classic wooden structure with a lower wing position and a cantilever tail assembly. The aircraft has a spring-type landing gear with a tail support.The power plant of the aircraft is a two-stroke two-cylinder air-cooled engine of the RMZ-640 type, which drives a two-blade wooden monoblock propeller through a V-belt reducer.
The control system of the Argo-02 aircraft is of a normal type. The cockpit is equipped with flight instruments and engine control instruments.
The fuselage of the aircraft is wooden, diagonally-truss construction. The fuselage spars are wooden slats with a section of 18X18 mm.
Behind the cockpit, on top of the fuselage, a light gargrot is installed, the basis of which is made up of foam diaphragms and stringers. There is also a gargrot in the front of the fuselage, in front of the cockpit - it is made of wooden diaphragms and sheathing of sheet duralumin with a thickness of 0.5 mm.
The cockpit is sheathed with 2.5 mm plywood. The tail section of the fuselage in the area of the stabilizer attachment is sheathed with the same plywood. All other surfaces of the fuselage are covered with linen.
The center section spars pass through the cockpit, which are used to attach the pilot's seat to them, as well as the aircraft manual control post. The armchair is molded from fiberglass and covered with artificial leather.
The sides of the cabin are covered with foam from the inside, and on top of it - with artificial leather. On the left side of the cockpit there is a throttle control - a handle for controlling the throttle valve of the engine carburetor.
The dashboard of the aircraft is knocked out of sheet duralumin and covered with the so-called hammer enamel. In the cockpit, it is attached to frame No. 3 with shock absorbers. The following devices are mounted on the dashboard: TGTs, US-250, VR-10, VD-10, EUP, TE and an ignition switch. There is a fuel cock under the board, and a filler syringe on the front spar.
In the front part of the fuselage, under the grotto, a fuel tank with a capacity of 15 liters is fixed.
In the lower part of the fuselage, in front of the front spar, chassis attachment points are installed. On the front frame, which is also a firewall, a lever-type pedal mounting unit and a foot control roller fixing unit are attached. On the other side of the firewall, a non-return valve, a fuel filter and a drain cock are mounted.
The engine mounts are installed at the points of joining the side members with the front frame. The motor mount itself is welded from chrome-steel (steel 30HGSA) pipes dia. 22X1 mm. Rubber shock absorbers are provided at the points of attachment of the engine to the engine mount. The engine is covered with upper and lower bonnets molded from fiberglass. The screw blank is glued from five pine sheets with epoxy glue and, after finishing, is covered with fiberglass using an epoxy binder.
Wing. The base of each wing is made up of a longitudinal and transverse set. The longitudinal one consists of a main spar, an auxiliary (wall), a frontal stringer and a streamline rib. The main spar is two-shelf; it consists of upper and lower flanges made of pine slats of variable cross-section: at the root of the wing, the upper flange is 30X40 mm, in the end section - 10X40 mm; the bottom shelf is 20X40 mm and 10X40 mm, respectively. Diaphragms are installed between the shelves in the region of the ribs. The spar is sheathed with 1 mm plywood on both sides; in the root part - with plywood 3 mm thick. Wooden bosses are installed in the wing root and in the aileron rocker attachment area.
The joints of the wing consoles with the center section are mounted in the root of the wing on the front (main) spar. Docking units are made of steel grade 30HGSA.
A mooring unit is mounted at the end of the spar.
The frontal stringer of the wing frame is made of a wooden lath with a section of 10X16 mm, the tail stringer is made of a lath with a section of 10X30 mm. From the nose to the front spar, the wing is sheathed with 1 mm plywood. A ladder is formed at the root of the wing made of 4 mm plywood.
The transverse wing set consists of normal and reinforced ribs. Reinforced (ribs No. 1, 2 and 3) have a beam structure and consist of shelves with a section of 5X 10 mm, racks and a plywood wall 1 mm thick with relief holes.
Normal ribs are truss. They are assembled from shelves and braces with a section of 5X8 mm, assembled using scarves and knits.
Wing tips - foam. After processing, they are pasted over with fiberglass on an epoxy binder.
Aileron is a slotted type. Its frame consists of a spar with a section of 10X80 mm, ribs cut from 5 mm thick plates, an attack rib and a streamline rib. The toe of the aileron is sewn up with 1 mm plywood, and together with the spar, the suturing forms a rigid closed profile resembling a semicircular pipe. The aileron hinge assemblies are mounted on the spar. The aileron response brackets are attached to the rear wing spar. All surfaces of both the aileron and the wing itself are covered with canvas.
Plumage. The horizontal tail of the Argo-02 aircraft consists of a stabilizer and elevators. Double-spar stabilizer with diagonally placed ribs - this provides the stabilizer with high torsional rigidity. The toe of the stabilizer up to the front spar is sheathed with 1 mm plywood. The stabilizer can be operated both in a cantilever and in a strut-braced version. To implement the second option, struts attachment points are installed on the rear spar. The stabilizer attachment points to the fuselage are mounted on the front and rear spars. The elevator hinge assemblies are located on the rear stabilizer spar; their design is similar to the arrangement of the A-1 airframe assemblies. The ends of the stabilizer are made of foam, covered with fiberglass.
The central part of the stabilizer is covered with plywood.
The elevator consists of two parts, which to some extent duplicate each other. Each of the parts consists of a spar, diagonally placed ribs, rib socks and a wrapping rib. The nose of the rudder is sheathed with 1 mm plywood. The elevator control hog is attached to the root of the rudder.
The vertical tail consists of a keel and rudder. The keel is structurally made integrally with the fuselage according to the two-spar scheme. The front part of the keel (up to the front spar) is sheathed with plywood. The rear spar is a development of the rear fuselage frame.
The rudder design differs little from the elevator and ailerons. It also consists of a spar, straight and diagonal ribs and a wrapping rib. The front part of the steering wheel is sewn with plywood to the side member. The rudder hinge assemblies are fork bolts. The steering lever is attached to the bottom of the side member. The strut attachment assembly is also mounted on the steering spar. The entire plumage is covered with linen.
Chassis. The aircraft landing gear consists of a main landing gear and a tail support. The main chassis is a two-wheeled, spring type. The spring is bent from 65G steel; the wheels are attached to the ends of the spring. The size of the wheel is 300X125 mm. Fastening the spring to the fuselage using a steel plate and two bolts on each side - the spring is clamped with their help and thereby fixed relative to the fuselage.
The tail support is a strip bent from 65G steel, to which a support cup is screwed from below. This strip is attached to the fuselage with two bolts.
Rigid elevator controls. It is carried out using a control knob (a handle from the Yak-50 is used), duralumin rods and intermediate rockers.
The aileron controls are also tight. The rudder drive is cable. It is controlled by means of suspended lever pedals, steel cables with a diameter of 3 mm and textolite rollers with a diameter of 70 mm. To exclude the ingress of foreign objects into the control units, the floor and control route are covered with a decorative screen.
Power point. The basis of the power plant is the engine of the RMZ-640 type. It is installed on the engine mount in an inverted position - down by cylinders. On top of the engine is the upper pulley of the V-belt gearbox with a belt tensioning mechanism.
Fiberglass hoods are screwed to self-locking anchor nuts on the fuselage and connecting ring.
The screw head is set on a duralumin ring and secured with screws. The spinner is made by gluing from fiberglass on an epoxy binder.
Fuel system. The fuel system includes a 14L fuel tank, fuel pump, fuel filter, check valve, fire cock, drain cock, tee and piping.
The fuel tank is welded from food grade aluminum sheet with a thickness of 1.8 mm. In the lower part of the tank there is a supply container, into which the supply and drain fittings are welded.
In the upper part of the tank there is a filler neck with a drain. There are interconnecting baffles inside the tank to prevent foaming of the fuel. The tank is secured to two beams using fastening straps with felt pads.
Air pressure receiver system. The LDPE system consists of a LDPE tube (from the Yak-18 aircraft) installed on the left wing plane, dynamic and static pressure tubes, connecting rubber hoses, a distributor and instruments.
Air propeller. The propeller of the Argo-02 aircraft is glued from pine plates on epoxy resin, and then processed according to templates, pasted over with fiberglass and painted. The aircraft used several propellers of this design with different diameters and pitches. One of the most acceptable in terms of its aerodynamic qualities has the following characteristics: diameter - 1450 mm, pitch - 850 mm, chord - 100 mm, static thrust - 85 kgf.
ATTENTION!!!
The calculation method below, as well as all the data
obtained using this technique are NOT
any instruction or guide to action,
a are given here for informational purposes only.
The author assumes no responsibility for the use of the data below.
The spar consists of two shelves, between which there are bulkheads and which are sewn on both sides with millimeter plywood. Thus, for our case, calculating the spar strength means calculating the height of each of the shelves. Moreover, this height is different for the upper and lower shelf. Let me explain why.
During normal flight, a lift is generated that tries to bend the wing upward:
And we see that the upper shelf is trying to shrink, and the lower one - to stretch. The shelves will be made of pine. And the pine is remarkable in that it has a very high rate tensile strength. But not a very good indicator of compressive strength. Thus, for the upper flange, which works in compression, a flange with a larger cross-section is required compared to the lower flange, which works in tension.
Now the calculation itself.
As initial data, we need the following values:
Gvzl - takeoff weight. Original 235 kg. I took 250 kg. (I already weigh about a hundred myself).
Gcr - wing weight. As in the original, I accept 13 kg.
ne is the value of the operational overload. As in the original, I take it equal to 3.
f is the safety factor. Recommended value: 1.2 - 1.5. But in Chumak's book "Calculation, design and construction of ultralight aircraft" it is recommended to take a value in the range of 1.5 - 2.0. I decided to take a value of 1.8.
nр is the destructive value of the overload. The value is obtained by multiplying ne by f. That. we get a value of 5.4.
Lcr - wingspan. For my case - 6.1 meters.
Lcons - length of one console = 2.775 meters.
H - spar height. To do this, subtract the thickness of the rib rails from the maximum profile height from the maximum profile height, which will go above and below the spar. Those. 155 - 5 - 5 = 145mm. For further calculations, we need a value in centimeters. Those. we will use the value 14.5 cm.
b - spar width - 40 mm = 4 cm.
T / t is the ratio of the height of the lower shelf to the upper one. The recommended value is 1.75.
The essence of the calculation is to calculate the cross-section of the flanges of the spar, which will collapse only when a destructive overload is reached. Those. according to our calculations, when an overload of 5.4g is reached, the spar will fall apart. In this case, the normal operating overload is 3. And it is dangerous to exceed this value. The coefficient f = 1.8 takes into account inaccuracies and minor errors in the manufacture of the spar and gives us a 2.4g reserve. But, again, it is better not to exceed the value of 3.
We will calculate the cross section at five points. To do this, we divide the wing into five equal sections.
Calculating the load at the last unnumbered point is irrelevant. Because in this place, the spar does not experience any loads and is only necessary to maintain the integrity of the entire structure.
The calculation itself.
1. Determine the linear breaking load on the wing. To do this, subtract the wing mass from the aircraft mass, multiply everything by the destructive overload value, and divide all this by the wing span. That. we get the value of the load per one meter of the wing length (I will not use the word "destructive", otherwise it is somehow not fun). For our case, we get:
q = (Gvzl - Gcr) * np / Lcr = (250 - 13) * 5.4 / 6.1 = 209.8 kg / lm.
There is one small question here, the answer to which I have not found. This is because we are dividing the load by the span of the entire wing. This value is the sum of the length of the two consoles and the width of the fuselage. The question is, should the fuselage width be included in the calculation? Or was it more correct to distribute the load only on the wings? On the forums where I asked the question, opinions were divided. Therefore, I decided to do it all the same as in the original - to include the width of the fuselage in the wingspan. Just information for overall development: in modern fighters, the fuselage creates 30% or more of the total lift.
2. In the previous step, we calculated the value of the load per linear meter of the wing. Now let's calculate the load value for each of the five wing points.
At the point
q0 = q * Lcons = 209.8 * 2.775 = 582.2.
On a section at a point
q1 = q * Lcons * 4/5 = 209.8 * 2.775 * 4/5 = 465.6.
Similarly for points 2 , 3 , 4 :
q2 = 209.8 * 2.775 * 3/5 = 349.3
q3 = 209.8 * 2.775 * 2/5 = 232.9
q4 = 209.8 * 2.775 * 1/5 = 116.4
3. For each of the points, we determine the value of the bending moment by the formula:
M0 = q0 * Lcons / 2 = 582.2 * 2.775 / 2 = 807.8 kg / m
Similarly for the rest of the points:
M1 = 465.6 * 2.775 * (4/5) / 2 = 516.8 kg / m
M2 = 349.3 * 2.775 * (3/5) / 2 = 290.8 kg / m
M3 = 232.9 * 2.775 * (2/5) / 2 = 129.3 kg / m
M3 = 116.4 * 2.775 * (1/5) / 2 = 32.3 kg / m
4. Using the previously calculated moments, calculate the value 58.3E by the formula:
58.3E = M / (b * H * H).
Honestly, I don't really remember what value 58.3E is, but in the next paragraph we will plot this value on the chart.
At the same time, one should pay attention to the fact that the value of the bending moment should already be taken not in kg / m, but in kg / cm. Those. increase this value a hundred times.
We get for each of the points:
58.3E_0 = 807.8 * 100 / (4 * 14.5 * 14.5) = 96.05
58.3E_1 = 516.8 * 100 / (4 * 14.5 * 14.5) = 61.45
58.3E_2 = 290.8 * 100 / (4 * 14.5 * 14.5) = 34.58
58.3E_3 = 129.3 * 100 / (4 * 14.5 * 14.5) = 15.4
58.3E_4 = 32.3 * 100 / (4 * 14.5 * 14.5) = 3.84
5. The values obtained in the previous step are plotted in the graph below and we obtain the T / H values
As you can see from the graph, it makes no sense to make calculations for points 3 and 4 - the values go beyond the graph.
A lone single-seat single-engine aircraft with a tailwheel named Margot. The owner is Victor Zhevagin. you can read about its construction. The aircraft is based on Argo-02.
As always, I use information from sites
http://www.airwar.ru
http://ru.wikipedia.org/wiki
and other sources I found in the internet and literature.
Single-seat self-made aircraft "MARGO". It was built in Privolzhsk Ivanovo region Victor Zhevagin. Launched in the air in 2015. It took 1st place among self-built aircraft. And now he takes part in the MAKS-2019 international aerospace show. Aircraft weight - 160 kg, flight speed - 130 km / h 
The power plant is a two-stroke 2-cylinder air-cooled engine RMZ-640, which drives a two-blade wooden monoblock propeller through a V-belt reducer. The aircraft's control system is of the normal type. The cockpit is equipped with flight instruments and engine control instruments. 
Compared to the original drawings of the Argo-02, there are changes in the design, mainly in the fuselage:
1. The center section is expanded to 1500 mm.
2. The fuselage is expanded along the upper spars up to 600 mm.
3. The 2nd and 3rd frames are moved back by 70 mm. Getting in and out of the cockpit has become more comfortable.
4. With the perspective of a closed cockpit, the height of the gargrot at the rear is increased.
5. The root rib of the center section is increased to 1200mm.
6. The chassis mounting brackets are installed on the front spar as in the KR-2. The spring is straight, made of a 25 mm thick fiberglass sheet. The chassis performed well and the cushioning was adequate. There were goats and plops without consequences. Glued wood spring made initially - broke on the first runs.
7. Changed rudder contour.
The wing is made as in the Model-Constructor, the changes are only in the tips. 
And now a little about its progenitor: The light single-seat aircraft "Argo-02" was built by craftsmen from Kalinin E. Ignatiev, Y. Gulakov and A. Abramov. For the manufacture of "Argo-02" used ordinary pine, plywood, canvas. The authors used the scheme of the classic cantilever low-wing aircraft forgotten by the home-builders, a simple Soviet RMZ-640 engine was installed. At the SLA-87 rally, the flights of "Argo-02" showed that the Kalinin homemade product flies better than some solid aircraft with imported engines. 
"Argo-02" is an ultralight training cantilever low-wing aircraft of a classic wooden structure with a cantilever tail assembly. The aircraft has a spring-type landing gear with a tail support. 
The fuselage is made of wood, with a diagonal truss structure, with spars made of wooden slats with a section of 18 x 18 mm. Behind the cockpit, on top of the fuselage, there is a light gargrot, which is based on foam diaphragms and stringers. There is also a gargrot in the front of the fuselage, in front of the cockpit it is made of wooden diaphragms and sheathing of sheet duralumin with a thickness of 0.5 mm. The cockpit and the aft fuselage in the area of the stabilizer attachment are sheathed with 2.5 mm plywood. All other surfaces of the fuselage are covered with linen. 
According to the calculations of the authors and the technical commission, the operational overload of the "Argo-02" was equal to 3, which is quite enough for circle flights and short routes. Aerobatics is categorically contraindicated for this device. Amateur aircraft designers shouldn't forget about it ... 
On August 18, 1990, while performing a demonstration flight at a holiday dedicated to the Day of the Air Force, Yuri Gulakov led the Argo into another coup. This time the speed turned out to be slightly higher than usual, and the maximum operational overload, obviously, far exceeded the calculated "three". As a result, the wing of the "Argo" fell apart in the air, and the pilot died in front of the assembled spectators. 
View of the dashboard from the other side. 
The plane is there, the tools are there, but there are no people :-))) 
General view on the right. 
LDPE from something larger? 
Interestingly, people of what height feel comfortable on such an airplane? 
Chassis. Garden cart rubber? 
General front view. 
Fixed pitch wooden screw. 
LTH "MARGO":
span 7.4 m.
length as original 4.55
empty weight 175 kg before painting
takeoff 255kg
screw Ф1600 mm
reducer 1: 2
speed max 4900
cruiser 4200
the screw is heavy for this reduction now make a new Ф1500 mm or is it already installed?
By speed:
from 50 km / h, it steers well with a raised tail
separation by 72-75 km / h
set at 85 km / h
vertical in the region of 2 m / s.
from 100 kg of the pilot, the rate of climb is 1 m / s.
cruising 100 km / h
maximum 120 km / h
landing approach 90 km / h
stall 60 km / h.
LTH of the original Argo-02:
Length, m: 4.55
Wingspan, m: 6.3
Wing area, m2: 6.3
Weight, kg
- empty: 145
takeoff: 235
Specific wing loading, kgf / m2: 37.3
Engine: RMZ-640
Max speed, km / h: 160
Cruising speed, km / h: 120
Stall speed, km / h: 72
Rate of climb, m / s: 2.
Is it realistic in our time to create an airplane on our own? Amateur aviators from Tver Yuri Gulakov, Yevgeny Ignatiev and Alexander Abramov were able to do this by building a single-seat aircraft, which was later named "Argo-02". The aircraft turned out to be good, they took part in republican competitions and won first place in the regional competition of amateur aircraft, which took place in Yaroslavl. This success of "Argo" was ensured, first of all, by the use of traditional, time-tested technologies for designing wooden aircraft with a modern miscalculation of the aerodynamic characteristics of this class of aircraft.
Perhaps this has become one of the main advantages of the aircraft: in its manufacture, plastic and composite materials, synthetic fabrics and high-strength rolled products are not needed at all. All that is needed is a pine log, linen, a little plywood and enamel.
Design
"Argo-02" is an ultralight trainer aircraft, represented by a cantilever low-wing aircraft of a classical design made of wood, which has a cantilever tail assembly. The device is equipped with a spring chassis with a tail support. As a power plant, a two-cylinder two-stroke air-cooled engine RMZ-640 is used, which, by means of a V-belt reducer, starts a two-blade monoblock wooden propeller into rotation.
In the cockpit there is a flight instrument cluster and indicator instruments that display the operation of the engine. The aircraft fuselage is wooden, has a diagonal truss structure, the spars are made of wooden slats (section 18x18 mm). Above the fuselage behind the cockpit there is a light gargrot, which is based on wooden stringers and diaphragms, as well as duralumin sheathing with a thickness of 0.5 mm.
The tail section of the fuselage and the cockpit are sheathed with 2.5 mm plywood. The remaining surfaces of the structure are covered with linen. Spars pass through the control cabin, to which a leather pilot's seat and an aircraft control post are fixed. From the inside, the sides of the cabin are covered with foam and artificial leather. The throttle is located on the port side. The dashboard is made of sheet duralumin, covered with enamel on top. Fastening of the dashboard is carried out by means of shock absorbers to frame No. 3. The front part of the fuselage under the gargrot is occupied by a fuel tank with a capacity of 15 liters.
In front of the front spar at the bottom of the fuselage are chassis attachment points. The front frame serves as a fire-prevention partition; it is equipped with pedal and foot control assemblies. On the other side of the firewall, there is a drain cock, a fuel filter and a non-return valve.
At the junction of the side members and the front frame, the engine mounts are installed. The motor mount is a frame of welded chrome-steel pipes with a diameter of 2.2 cm. The engine is fastened to the motor mount using rubber shock absorbers. The motor is completely covered by the lower and upper fiberglass hoods.
Plumage
Each wing center section consists of transverse and longitudinal sets. The longitudinal set is represented by two spars (main and auxiliary), a frontal stringer and flow ribs. As part of the transverse wing set, there are reinforced and normal ribs. Wing ailerons are slotted. All wing surfaces are sheathed with canvas.
The horizontal tail in "Argo-02" is represented by the elevator and stabilizer. The latter consists of two spars and diagonally located ribs, which ensures high torsional rigidity. The elevator is composed of two parts duplicating each other. Each of them consists of a spar, a set of diagonally positioning ribs and flow ribs. It is sheathed with plywood 1-3 mm thick.
The vertical tail of the aircraft is represented by the keel and rudder. The frontal part of the keel has a plywood sheathing. The rear fuselage frame is joined to the rear spar. The rudder is structurally similar to an elevator or aileron. The elevator control stick is fixed at the bottom of the side member. In order to avoid the penetration of third-party objects into the control units, the rods and cables are covered with a decorative screen. All surfaces of the tail have a linen sheathing.
Chassis
The aircraft is equipped with a spring-type two-wheeled main landing gear. The size of the wheels is 300x125 mm. A steel spring is attached to the fuselage on each side with a few bolts and a steel plate. The tail strut is also made of steel. It is fastened to the fuselage by screwing the support cup, which is part of the tail support, with two bolts.
Aircraft performance data
Length, m ............................................... .... 4.55
Height, m ............................................... .... 1.8
Wingspan, m ......................................... 6,3
Wing area, m2 .................................... 6,3
Narrowing of the wing ............................................. 0
Terminal chord of the wing, m .......................... 1,0
MAR, m ............................................... ......... 1.0
Installation angle of the wing, degrees ....................... 4
Angle V, degrees .............................................. ....4
Sweep angle, degrees ......................... 0
Wing profile ............................ Р-Ш 15.5%
Aileron area, m2 ............................. 0.375
The scope of the aileron, m ...................................... 1,5
Aileron deflection angles, degrees:
Up................................................. .......... 25
way down................................................. ............16
Sweep GO, m ............................................ 1, 86
GO area, m2 ......................................... 1,2
Installation angle of HE, degrees ............................. 0
RV area, m2 ..................................... 0.642
VO area, m2 ....................................... 0.66
VO height, m ............................................. 1 , 0
Area PH, m2 ....................................... 0,38
Angle of deflection PH, degrees .....................- 25
RV deflection angle, degrees ......................- 25
The width of the fuselage in the cockpit, m ............ 0.55
Fuselage height in the cockpit, m ............. 0.85
The chassis base, m ............................................. 2 ,nine
Track chassis, m .......................................... 1,3
Engine:
Type of................................................. ..RMZ-640
power, HP ............................................ 28
Max. rotation frequency, rpm ......... 5500
Reducer:
Type ...................................... V-belt,
four-strand
gear ratio .................................. 0.5
belts, type ........................................... A-710
Fuel ...................................... gasoline A-76
Butter................................................. .MS-20
Screw diameter, m ....................................... 1,5
Propeller pitch, m ............................................ 0, 95
Static thrust, kgf ................................. 95
Weight of the empty apparatus, kg ..................... 145
Maximum takeoff weight, kg ......... 7235
Fuel capacity, l .......................................... 15
Range
flight balance,% MAR ............ 24. ..27
Stall speed, km / h ........................ 72
Max. speed
horizontal flight, km / h ................. 160
Maximum
piloting speed, km / h ................ 190
Cruising speed, km / h ..................... 120
Tear-off speed, km / h ............................... 80
Landing speed, km / h ........................ 70
Climb rate at sea level, m / s .................. 2
Take-off run, m ............................................... .....100
Mileage, m ............................................... ...... 80
Range
operational overloads ....... + 3 ..- 1.5
Argo 02 videos
Is it possible in our time to build an airplane on your own? Tver amateur aviators Yevgeny Ignatiev, Yuri Gulakov and Alexander Abramov answered this question in the affirmative, creating a winged one-seater aircraft, later named "Argo-02". The plane turned out to be successful: it successfully flew at all-Union competitions, was the first prize-winner of the regional competition of amateur flying vehicles in Yaroslavl. The secret of the increased popularity of "Argo" among amateur aviators is not in the design or technological sophistication of the designers, but rather in their tradition. The designers managed to achieve a successful combination of the methods of designing wooden cars of the 1920s and 1930s, worked out over many decades, and modern aerodynamic calculations of aircraft of this class. This, perhaps, is one of the main advantages of the aircraft: modern plastics and composites, rolled products from high-strength metals and synthetic fabrics are not required at all for its manufacture - only pine beams, a little plywood, linen and enamel are needed.
However, the simplest construction of common materials is just one of the components of the success of the machine. In order for all these pine slats and pieces of plywood to "fly", they must be "fit" into certain aerodynamic shapes. In this case, the authors of "Argo" - we must give them their due - showed an enviable design flair. For their aircraft, they chose the aerodynamic design of a classic cantilever low-wing aircraft with a pulling propeller.
Nowadays, against the background of a wide variety of "ducks", "tandems" and other wonders of modern aerodynamics, the plane of the "Argo" looks even conservative. But this is precisely the wisdom of the aircraft designer: if you want to build a successfully flying plane, choose the classic scheme - it will never fail.
However, this is not all. For an aircraft to fly well, it is necessary to correctly determine the ratio of its mass, engine power and wing area. And here the parameters of "Argo" can be considered optimal for a device with a motor with a capacity of only 28 hp.
If someone wants to build such an aircraft, the parameters of the "Argo" can be taken as an example: it is precisely this ratio that provides the best flight performance: speed, rate of climb, takeoff run, mileage, etc.
At the same time, the stability and controllability of the aircraft is determined by the ratio of the wing area, empennage and rudders, as well as their relative position. And in this area, as it turned out (which the designers of "Argo" perfectly understood!), So far no one has invented anything better than the standard classical scheme. And for "Argo" the parameters are taken directly from the textbook: the area of the horizontal tail is 20% of the wing area, and the vertical - 10%; the empennage shoulder is equal to 2.5 of the aerodynamic chord of the wing, and so on, without any deviations from the classical design rules, which, obviously, there is no point in departing from.
1 - propeller spinner (glued from fiberglass); 2 - propeller (pine re-glue); 3 - V-belt reducer; 4 - engine of the RMZ-640 type; 5 - sub-engine frame (pipes made of steel 30HGSA); 6 - tachometer sensor; 7 - check valve; 8 - firewall; 9 - fuel tank filler flap; 10 - compensator; 11 - fuel tank (sheet aluminum); 12 - instruments (navigation and flight control and engine operation control); 13 - visor (plexiglass); 14-handle for controlling the throttle valve of the engine carburetor (throttle); 15 - roll and pitch control stick; 16 - pilot's seat (glued from fiberglass on epoxy binder); 17 - chair back; 18 - block of rollers for wiring control cables; 19 - intermediate rocking chair of the elevator; 20 - rudder thrust; 21 - engine hood (glued from fiberglass on epoxy binder); 22 - fuel filter; 23 - motor mount mounting unit; 24 - suspended heading control pedals; 25 - spring chassis attachment unit; 26 - chassis wheel 300 × 125 mm; 27 - chassis spring (steel 65G); 28 - filler syringe; 29 - control rod of the elevator; 30 - fairing (gluing from fiberglass on epoxy binder); 31 - intermediate rocker for elevator control; 32 - block of rollers for rudder control cables; 33 - rudder control cable; 34 - thrust for elevator control; 35 - block of rollers for routing rudder control cables; 36 - rudder drive lever; 37 - tail support (crutch)
1– control knob; 2– handle for controlling the throttle valve of the engine carburetor (throttle); 3 - THC; 4 - BP-10; 5 - EUP; 6 - US-250; 7 - VD-10; 8 - TE-45; 9 - shock absorber; 10-fuel tank; 11– fire hydrant; 12 - course control pedals
1 - roll and pitch control stick; 2 - handle for controlling the throttle valve of the engine carburetor (RUD); 3– rudder; 4– elevator; 5 - aileron; 6 - course control pedals
Although aerodynamic data allow the aircraft to perform aerobatics, aerial acrobatics is not only successful aerodynamics, but also high structural strength. According to the calculations of the authors and the technical commission, the operational overload of the "Argo" was equal to 3, which is quite enough for flights in a circle and short routes. Aerobatics is categorically contraindicated for this device.
Amateur aircraft designers should not have forgotten about this ... On August 18, 1990, when performing a demonstration flight at a holiday dedicated to the Day of the Air Force, Yuri Gulakov introduced the Argo into another coup. This time the speed turned out to be slightly higher than usual, and the maximum operational overload, obviously, far exceeded the calculated "three". As a result, the wing of the "Argo" collapsed in the air, and the pilot died in front of the assembled spectators.
As a rule, such tragic cases, even with all the obviousness of the reasons causing them, make us look for errors in the design of the aircraft and in the calculations. As for the "Argo-02", the car withstood exactly as long as it was designed for. That is why the technical and flight-methodological commissions for amateur-built aircraft of the Ministry of Aviation Industry at one time recommended "Argo-02" as a prototype for self-construction.
"Argo-02" is an ultra-light training cantilever low-plan classic wooden structure with a cantilever tail assembly. The aircraft has a spring-type landing gear with a tail support.
The power plant is a two-stroke 2-cylinder air-cooled engine RMZ-640, which drives a two-blade wooden monoblock propeller through a V-belt reducer. The aircraft's control system is of the normal type. The cockpit is equipped with flight instruments and engine control instruments.
The fuselage is made of wood, with a diagonal truss structure, with spars made of wooden slats with a section of 18 × 18 mm. Behind the cockpit, on top of the fuselage, is a light gargrot, which is based on foam diaphragms and stringers. There is also a gargrot in the front of the fuselage, in front of the cockpit it is made of wooden diaphragms and a cladding of sheet duralumin 0.5 mm thick. The cockpit and the aft fuselage in the area of the stabilizer attachment are sheathed with 2.5 mm plywood. All other surfaces of the fuselage are covered with linen.
The center section spars pass through the cockpit, to which are attached the pilot's seat molded of fiberglass and covered with artificial leather and the aircraft manual control post.
The sides of the cabin are covered with foam from the inside, and on top of it - with artificial leather. On the left side there is a throttle control - a handle for controlling the throttle valve of the engine carburetor.
The dashboard is knocked out of sheet duralumin and covered with hammer enamel. In the cockpit, it is attached to frame No. 3 with shock absorbers. On the board itself, devices are mounted: TGTs, US-250, VR-10, VD-10, EUP, TE and an ignition switch, under the board there is a fuel tap, on the front spar there is a filler. In the front part of the fuselage, under the gargrot, a fuel tank with a capacity of 15 liters is fixed.
In the lower part of the fuselage, in front of the front spar, chassis attachment points are installed. On the front frame, which is also a firewall, a lever-type pedal hinge unit and a roller fixation unit and foot control are mounted. On the other side of the firewall is the check valve, fuel filter and drain cock.
The engine mounts are installed at the joints of the spars with the front frame. The motor mount itself is welded from chrome-steel (steel 30GSA) pipes with a diameter of 22 × 1 mm. The engine is attached to the engine mount via rubber shock absorbers. The power plant is covered with upper and lower fiberglass hoods. The screw blank is glued from five pine sheets with epoxy resin and, after finishing, covered with fiberglass using an epoxy binder.
The basis of each wing is longitudinal and transverse sets. The first consists of two spars - the main and the auxiliary (wall), the frontal stringer and the streamline rib. The main spar is a double-shelf, the upper and lower shelves are made of pine slats of variable cross-section. So, the section of the upper flange: at the root of the wing - 30 × 40 mm, and at the end - 10 × 40 mm; bottom - 20 × 40 mm and 10 × 40 mm, respectively. Diaphragms are installed between the shelves in the region of the ribs. The spar is sheathed with 1 mm plywood on both sides; in the root part - with plywood 3 mm thick. Wooden bosses are fixed in the wing root and in the aileron rocker attachment area.
The joints of the wing consoles with the center section are mounted in the root of the wing on the front (main) spar. They are made of steel grade 30HGSA. There is a mooring knot at the end of the spar.
The frontal stringer of the wing frame is made of a wooden strip with a section of 10 × 16 mm, the tail stringer is made of a strip with a section of 10 × 30 mm.
From the nose to the front spar, the wing is sheathed with 1 mm plywood. A ladder is formed at the root of 4 mm thick plywood.
The transverse wing set includes normal and reinforced ribs. The latter (ribs No. 1, No. 2 and No. 3) have a beam structure and consist of shelves with a cross section of 5 × 10 mm, racks and a plywood wall 1 mm thick with relief holes. Normal ribs are truss. They are assembled from shelves and braces with a section of 5 × 8 mm using kerchiefs and knits. Wing tips - foam. After processing, they are pasted over with fiberglass on an epoxy binder.
Aileron - slotted type with a frame made of a spar with a section of 10 × 80 mm, ribs made of plates 5 mm thick, an attack rib and a streamline rib. The sock is sewn up with 1 mm plywood; together with the spar, the lining forms a rigid closed profile, reminiscent of a semicircular pipe. The aileron hinge assemblies are mounted on the spar, and the reciprocal hinge brackets are mounted on the rear wing spar. All surfaces of the aileron and the wing itself are covered with canvas.
The horizontal tail of the Argo-02 aircraft consists of a stabilizer and elevators. The stabilizer is two-spar, with diagonally located ribs, which provides it with high torsional rigidity. The toe up to the front spar is sheathed with 1 mm plywood. The stabilizer can be used both in a cantilever and in a strut-braced version. The second option involves the installation of strut attachment points on the rear spar. The stabilizer attachment points to the fuselage are mounted on the front and rear spars. The elevator hinge assemblies are located on the rear stabilizer spar; their design is similar to the arrangement of the A-1 glider assemblies. The ends of the stabilizer are foam plastic, covered with fiberglass, the central part is sheathed with plywood.
The elevator is of two parts, which to some extent duplicate each other. Each of the parts consists of a spar, diagonally placed ribs with socks and a flow rib. The nose of the rudder is sheathed with 1 mm plywood. The elevator control hog is fixed in the root part.
The vertical tail of the aircraft is the keel and rudder. The keel is structurally made integrally with the fuselage according to the two-spar scheme. Its frontal part (up to the front spar) is sheathed with plywood. The rear spar is a development of the rear fuselage frame.
The rudder is similar in design to an elevator or aileron. It also consists of a spar, straight and diagonal ribs and a wrapping rib. The front part of the steering wheel is sewn with plywood to the side member. Hinge units are fork bolts. The control lever is fixed at the bottom of the side member. The strut attachment unit is also mounted there. The entire plumage is covered with linen.
The main landing gear of the aircraft is a two-wheeled, spring type. The spring is bent from 65G steel; wheels with dimensions of 300 × 125 mm are attached to its ends. The spring is attached to the fuselage with a steel plate and a pair of bolts on each side, with which the spring is clamped and thereby fixed relative to the fuselage.
The tail support is a 65G steel strip attached with two bolts to the fuselage, to which a support cup is screwed from below.
1 - carburetor; 2 - check valve; 3 - fuel filter; 4 - consumable container; 5 - tank plug with drainage; 6 - fuel tank; 7 - fire hydrant; 8 - supply connection; 9 - drain fitting; 10 - drain valve; 11 - filler syringe
1– static pressure distributor; 2– dyurite hose; 3 - aluminum pipeline; 4 - air pressure receiver (LDPE)
The elevator control is rigid, with a handle (from the Yak-50 aircraft), duralumin rods and intermediate rockers. The aileron controls are also tight. Steering wheel drive - cable, using suspended lever pedals, steel cables with a diameter
3mm and textolite rollers with a diameter of 70 mm. To exclude the ingress of foreign objects into the control units, the floor and the track of the rods and cables are covered with a decorative screen.
The power plant of the aircraft is based on an engine of the RMZ-640 type, mounted on the engine mount in an inverted position - with the cylinders down. On top of the engine is the upper pulley of the V-belt reducer with a belt tensioning mechanism. Fiberglass hoods are screwed to self-locking anchor nuts on the fuselage and connecting ring.
The propeller is glued with epoxy resin from pine plates, and then processed according to templates, covered with fiberglass and painted. Several of these propellers with different diameters and pitches were used on "Argo-02". One of the most acceptable in terms of its aerodynamic qualities has the following characteristics: diameter - 1450 mm, pitch - 850 mm, chord - 100 mm, static thrust - 85 kgf. The screw head is glued from fiberglass on an epoxy resin and set on a duralumin ring. Fastening the spinner to the propeller with screws.
The aircraft's fuel system includes a 14 liter fuel tank, fuel pump, fuel filter, check valve, fire cock, drain cock, tee and piping system.
The fuel tank is welded from a 1.8 mm thick aluminum sheet. In the lower part there is a supply container, into which the supply and drain fittings are welded, in the upper part there is a filler neck with drainage, inside there are communicating partitions to prevent foaming of the fuel. The tank is secured to two beams using fastening straps with felt pads.
The air pressure receiver system (APS) consists of an APS tube (from the Yak-18 aircraft) installed on the left wing plane, dynamic and static pressure tubes, connecting rubber hoses, a distributor and devices.
Aircraft performance data
Length, m …………………………………………… 4.55
Height, m …………………………………………… 1.8
Wingspan, m ………………………………… ..6,3
Wing area, m2 ……………………………… 6.3
Narrowing of the wing ……………………………………… 0
Terminal chord of the wing, m …………………… ..1,0
MAR, m ……………………………………………… .1,0
Wing mounting angle, degrees ………………… ..4
Angle V, deg ………………………………………… ..4
Sweep angle, degrees …………………… .0
Wing profile ……………………… .Р-Ш 15.5%
Aileron area, m2 ……………………… ..0,375
Aileron span, m ……………………………… ..1,5
Aileron deflection angles, degrees:
up ………………………………………………… ..25
down …………………………………………………… .16
RV span, m …………………………………… ..1.86
GO area, m2 ………………………………… ..1,2
HE installation angle, degrees ……………………… ..0
RV area, m2 ……………………………… .0.642
VO area, m2 ………………………………… 0.66
VO height, m ……………………………………… 1.0
Area PH, m2 ………………………………… 0.38
Angle of deflection PH, degrees ………………… - 25
RV deflection angle, degrees ………………… .- 25
Fuselage width along the cockpit, m ... ... ... ... 0.55
Fuselage height along the cockpit, m ………… .0.85
Chassis base, m ……………………………………… 2.9
Chassis track, m …………………………………… 1.3
Engine:
type …………………………………………… RMZ-640
power, hp …………………………………… ..28
Max. rotation frequency, rpm ... ... ... 5500
Reducer:
type ……………………………… .. V-belt,
four-strand
gear ratio …………………………… .0,5
belts, type …………………………………… .А-710
Fuel ……………………………… .. gasoline А-76
Oil ………………………………………… ..MS-20
Screw diameter, m ………………………………… 1.5
Screw pitch, m …………………………………… ..0.95
Static thrust, kgf …………………………… 95
It might be helpful to read:
- Massage, massage products Nem Yandex Direct massage parlor Sorry;
- How to start a bakery from scratch - a guide and a business plan Bakery pleasure for all customers;
- Auto shelf - wholesale supplies;
- Ideas for a profitable business;
- What is second hand and stock clothes?;
- Making ritual wreaths;
- How to keep records in an online store: accounting, tax and product accounting;
- Business plan: how to start a business selling meat;