Introducing the Avia 51

[Milton Shupe]

looks great! nice art deco styling....

might build an Avia Hangar to store these beauties in.... keep it classical modern/Art Deco with the Avia Logo on... would look good i think.... will see how we go, then theres the headache of "Where do we put the bally thing"

Seems to be lots of free space around Pravda :-)

[Drzook]

Avia 56 Protype - Shortly after concluding design work for the Avia 51, Robert Nebesar and team started work on a single-engine high-wing commercial monoplane designated Av-56. It was to be powered by a 600 HP (441kW) Avia Rr-29 nine-cylinder radial engine. However, problems with that engine required reworking the aircraft design to use the liquid-cooled, inline Avia Hispano Suiza 12 Ybrs engine. So the type Av-156 was born and a prototype built.

This simulation model is the Avia 56 that did not get built, but you get to fly this beautiful aircraft in four configurations - wheels, floats, amphibs, and skis - with some of the best sounds and textures to grace your FS9 sim.

Here are some WIP shots. I hope that Nigel doesn't mind. :-)

EDIT: And this is just a peek; there are more ... :-)

Looks like the love child of a Lockheed Vega and a Vultee V-1. Beautiful.

[aardvark62]

An alternative floor panel for the float/amphib versions of the Avia 51 - hopefully gives it more of the cargo hauler/bush flyer feel:

Attachment 61263

The bmp was edited from another floor panel bmp from Milton's D18. If anyone is interested, and it's OK with Milton, I'll happily put this up.

A.

[Milton Shupe]

An alternative floor panel for the float/amphib versions of the Avia 51 - hopefully gives it more of the cargo hauler/bush flyer feel:

Attachment 61263

The bmp was edited from another floor panel bmp from Milton's D18. If anyone is interested, and it's OK with Milton, I'll happily put this up.

A.

Not a problem A. I appreciate anyone who offers enhancements.

[aardvark62]

An alternative floor panel for the float/amphib versions of the Avia 51 - hopefully gives it more of the cargo hauler/bush flyer feel:

Attachment 61263

The bmp was edited from another floor panel bmp from Milton's D18. If anyone is interested, and it's OK with Milton, I'll happily put this up.

A.

Please find below a zip containing the alternative bmp.
Attachment 61270

Regards, A.

[Rallymodeller]

With the Avia 56 coming around the 3-4 turns, I am back doing the "heavy lifting" on the Avia 57, the last in the Avia Projects series.

The Av-57 was to be a 14 passenger, 2 pilot commercial aircraft built to compete for traffic with the DC-2 in the mid-30's. This was the last of the Robert Nebesar designs as far as we can determine. The prototype was constructed and had 27 test flights performing well in all tests as did the Avia 156 with 30 flights.

However, all hope for the two prototypes ended fatally April 15, 1935. Both prototypes took off for test flights, one after the other, and somewhere north of Kbely airport, the tragic event took place. First, the 156 lost part of a wing, then the tail, and in a spin lost the balance of the wing crashing near the village of Polerady. Within 7 minutes the Avia 57 fell to the ground after the wing and tail separated in a spin. All pilots and technicians aboard lost their lives. As no one witnessed the event, the most likely cause was a mid-air collision.

The loss of the prototypes and the investigation that followed questioning the structural integrity of the designs threw a shadow over the Avia company and the design team of Dr. Ing. Nebesar.

This beautiful Avia 57 aircraft will fly again in FS9 along with the Av-51, Av-156, and the Av-56 in honor of the Avia Company and Dr. Ing. Nebesar.

Wow -- wonder if Fiat was engaged in a little corporate espionage with the G.12?

[Milton Shupe]

Probably not necessary as its first flight was in 1940. The Avia 57 flew in 1935. Both were 14 passenger initially, although with time, the G-12 had access to better, larger engines and eventually became a 18 and 22 passenger carrier as well as long range transports. It did inspire the G-212 the last of the Italian 3-engine commercial aircraft.

[Milton Shupe]

Avia 57 WIP today ... fuselage, wings, tail, gear, flaps, interior floor, panels etc. coming along.

[Sunny9850]

Simply stunning what you mold out of thin air sir.

Cheers
Stefan

[Milton Shupe]

Simply stunning what you mold out of thin air sir.

Cheers
Stefan

Thank you sir; I often wonder how I do this myself ...

Wrapping up the major components on the exterior model and molding the new flight model into shape, and caught this screen shot and decided it would be appropriate in black and white and edged. Makes a nice Desktop Background.

[Blackbird686]

Looking good Milton I'll be following this one closely. Just look at thos big tires! Wonder how she'd do as a bush flyer.... taking people in and out of Africa on safari trips!

BB686

[Milton Shupe]

Looking good Milton I'll be following this one closely. Just look at thos big tires! Wonder how she'd do as a bush flyer.... taking people in and out of Africa on safari trips!

BB686

Thanks BB. I was a bit surprised by the size of the wheels and tires myself, very deceiving. 1500 x 300 mm or 59" inches by 11.8".

[Sunny9850]

I think the big wheels are serving two design criteria here, relatively unprepared fields of the day which likely mostly consisted of grass runways and the large diameter raises the nose high for a good angle of attack for the wings on takeoff and ground clearance for the props without requiring long landing gear arms.

Cheers
Stefan

[Milton Shupe]

Thanks to Hurricane91 and Tomas for the data and translations.

Avia Av-57

The fuselage was all-metal construction. Eight main longerons were shape as first picture in the text. Main longerons carried loads from wings and undercariage. The others longerons were shape as second picture in the text. Eleven bulkheads were riveted, the others were made from profiles of shape in third picture.

Tail surfaces were all-metal costruction. The frame was made from opened dural profiles. Stabilizer was adjustable during flight. Control surfaces were equiped by flettners and fitted with ball bearings.

Pilot's cabin was enterable thru the door from passenger's cabin.
The windshild was made of shatter-proof glass. Side windows were opened.
Left pilot's seat was adjustable up-down.
Pilot on the right seat operated radio station.
There was an emergency exit on the cabin ceiling.
Wheel controls were dual. Pedal controls were adjustable.

Compressed air brakes was controlled by lever on the steering wheel together with pedal controls (see the photo of A-204, which I sent you earlier - it's the same system).
Stabilizer was controlled by stabilizer control wheel. Two flettner control wheels were placed on rear wall of the cab.
Throttle levers and setting of fuel mixture were under dashboard.
Flaps lever was under throttle levers.
Lever for retracting undercarriage was on the left side of the pilot. Emergency control of undercarriage extension was between pilot seats.

Main undercarriage had oleo-pneumatic shock absorber. Rectraction was operated by hydraulic hoist.
Undercarriage has been extended by its own weight and pushed by air pistons and cables.
Size of main Wheels were 1500 x 300 mm. Tail weel was size 600 x 200 mm.
Tail wheel was also oleo-pneumatic shock absorber and full castoring.

The passenger cab was upholstered by waterproof fabric. The upholstery was added by some polished material in upper and lower parts.
Windows had a dimension 27 x 41 cm.
Passenger's seats had armrests and seat belts. There were twelve padded chairs and two folding seats in the cabin.
Air vent and heating were providing to each seat.
Over the passenger's seats there were nets for in-cabin baggage.
Some instruments were mounted in the passenger cabin. (They may have been indicators altimeter, airspeed indicator and real-time clock as in Aero A-204 - see the photo)
Dimension of the cabin was: 1,78 m height, 1,75 m width, 6 m lenght.
Entrance door was situated on the port side behind the wing.
Toilet with washroom was behind the passenger's cabin.
There were two emergency exits - the first was on the starboard in the rear and the second on the port side forward.

Baggage spaces there were placed under the pilot's cabin, behind the toilet and in the wing.
Capacity of rear baggage compartment was 2,3 m3, total capacity of all compartment was 4,14 m3.

Other equipment: navigation lights, two accumulators, radio station, hand-held fire extinguisher, first-ait treatment box, tool kit.

Engine assembly consisted of three Hispano Suiza 9V engines (license of Wright Cyclone 1820-1).
Airscrews Hamilton were in-flight adjustable.
Engine beds were welded of steel tubes and attached via four bolts.
The engines were covered with aerodynamic NACA cowlings and equipped by extinguishing system.
The overall volume of four fuel tanks was 1600 litres.
Each of the three oil tanks was volume 58 litres.
The fuel and oil tanks were welded of aluminium.

Dimensions:
Aircraft lenght...........................15,90 m
Aircraft height.............................4,45 m
Wing span................................22,50 m
Maximum width of the fuselage....1,90 m
Wing surface............................81,50 m2

Engines:
3 engines 575 KS.......................1725 KS (KS = HP)
Drive.........................................dire ct (without reducer)
Weight of engine with accessory..430 kg

Cargo capacity:
Crew (1 person and radio operator)...160 kg
12 passengers................................960 kg
Mail and baggage...........................300 kg
In-cabin baggage............................180 kg
Total............................................1 600 kg

Fueling:
Petrol..........................1130 kg
Oil................................135 kg
General characteristics
Crew: 2
Capacity: 14
Length: 15.90 m (52 ft 2 in)
Wingspan: 22.50 m (73 ft 10 in)
Wing area: 81.5 m2 (877 sq ft)
Powerplant: 3 × Hispano-Suiza 9Vd radial piston engine, 429 kW (575 hp) each
R-1820-1

Performance
Maximum speed: 300 km/h (190 mph; 160 kn); 330km/h (205mph at 5000')
Cruising speed: 270 km/h (178 mph; 150 kn)
Range: 1,200 km (746 mi; 648 nmi)
Service ceiling: 4,000 m (13,123 ft)

Special accessories:
Battery, radio................85 kg

Weights:
Weight of aircraft (with instruments, seats, wiring)......5600 kg
Cargo............................................. ........................3000 kg
Take-off weight............................................ ............8600 kg

Minimal performances:
For standard air density CINA 1,225 kg/m3 and full load (CINA was precursor ICAO)
Maximum speed near ground........................330 km/h
Cruise speed near ground.............................280 km/h
Initial climbing.......................................... .......6 m/s
Maximum ceiling........................................560 0 m
Operative ceiling.........................................50 00 m
Operative ceiling with two engines................2000 m
Flying range............................................. ..1200 km (745miles)
Climbing from 0 to 500 m...............................1' 8 min
Climbing from 500 to 1000 m..........................2' 2 min
Climbing from 1000 to 2000 m........................5' 2 min
Gliding when two engines are stopped................1:25
Take-off............................................... ........200 m
Landing........................................... ............200 m

************************************************** **********************************

[Rallymodeller]

I think the big wheels are serving two design criteria here, relatively unprepared fields of the day which likely mostly consisted of grass runways and the large diameter raises the nose high for a good angle of attack for the wings on takeoff and ground clearance for the props without requiring long landing gear arms.

Cheers
Stefan

Some prewar French trimotors (I'm thinking Dewoitine D.333 and D.338, and Couzinet 70) had a similar giant wheel thing happening. Having big, bouncy tires also lowers the complexity requirement of the landing gear, as the tire itself does a lot of the shock-absorbing action.