Giants

"Bigger is better." That is a phrase many pilots of larger airplanes use. We will not say that they are wrong or right. We will simply try to tell why there are huge airplanes.

Two of the three reasons to build a giant are range and payload. Since the beginning of aviation designers made plans of giants to have a longer range. The Germans made plans for a huge bomber, the Mannesmann Poll, to attack the United States of America. It was a ten-engine tri-plane. It had 5 engine gondolas with each 2 engines. 4 gondolas were mounted on the mid wing, 1 gondola was mounted on the lower wing (in the middle of the wing). At the end of that war the Allied forces found a wheel of that bomber, so production of parts had already begun. The wheel had a diameter of 2.2 meter!

Engines     10      
Span     50 m     164.04 ft
Length     45.7 m     150 ft
Range     10 500 km (130 km/h)     6524 mi

Between the wars there were many firms who wanted to have larger airplanes, so they could move more people over a longer range. Larger airplanes need longer airstrips. Since there were no long airstrips available at that time, flying boats were introduced. Most of the giants between the wars were flying boats. Sikorsky, Short and several other firms built their flying boats. But the most remarkable flying boat of that time was surely the German Dornier Do X. This giant had 12 engines mounted on top of the wing. The interior was pure glitter and glamour. But the project itself was an economical disaster. Even 12 engines were not enough to put some speed or height into this plane. Even Lufthansa (German airlines) was not interested to buy a Dornier X.

Own remark: learning a bit more about airplanes, I changed my point of view on the Dornier X. I now wonder if the airplane really was underpowered. Could it be that the pilots flew low on purpose to use the Wing In Ground-effect (WIG)? This could have given the wing more lift and would result in less fuel consumption during a long flight. People, who have more info about this, please send me your remark. 

Thomas Labruyère gave me a link to a GOOD site about WIG. http://www.se-technology.com/wig .

Thomas Labruyère wrote me:"I've seen a picture of this huge plane over New York Harbour, at an altitude of several hundred meters, so it could be flown out of ground effect. Of course, flying low would increase on such aircafts the overall range and even maybe the speed (the Cx being reduced due to the absence of turbulence over the wing upper surface (my technical english is getting a bit rusty lately). But you've got to fly at less than half the wingspan to benefit from ground effect. It would bring the Dornier really low, especially when the wing is above the fuselage. Just a thought of my own, of course, I have no real expertise in that field."

Dornier Do X
Power     12 x 391.5 kW (525 hp)
12 x 477 kW (640 hp)
12 x 432 kW (580 hp) (Do X2 en Do X3)
Span     48 m     157.4 ft
Length     40 m     131.2 ft
Height     10 m     32.8 ft
Wing area     450 m2     4844 sq.ft.
Weight (empty)     32 675 kg     72 035 lb
Weight (maximum take-off)     56 000 kg     123 457 lb
Speed (maximum)     214 km/h     133 mph
Speed (cruise)     190 km/h     118 mph
Ceiling     1250 m     4100 ft
Range     1700 km     1056 mi

I got a email from Rit Staalman:

"Yes the Dornier Do-X was underpowered.
In 1929 sufficiently powerful and reliable engines were simply not available
also the design ran overweight during production, some 5000 kilogram, or ten percent of the design weight (48000 kg)
which is enough to kill any design, because the netto useful load on a real airplane of that time was normally < 10%
Also designers of that time had little idea of the drag that was caused by struts and things like the anchor carried on the bow.
Yes the pilots flew low to make use of the ground effect of the stubby wings.
But it must be admitted: most (long distance) pilots of that era flew low (read Lindbergh)
Winds were usually less near the ground and the stratosphere had not yet been conquered.

And also: for long distance flight the wings should not have been stubby, but long and slender (see an albatross)
but that would have given a much heavier construction at the wing root;
or Dornier should have taken for granted smaller wings,
but smaller wings would have meant higher wing loads
and higher wingloads imply more powerful engines,
so we are in a quandary,
or rather HE, Dornier,  was.

Still, he was the first to build a real large airplane OUT OF METAL
and it flew!
Chapeau!"

 

 

The Dornier Do X was an answer to the request of the Reichsverkehrministerium (RVM). Their "Vorbereiting des Transozeanischen Luftverkehrs" (preparation for transatlantic air travel) got several proposals. There were several proposals that couldn't be achieved in that time. Rumpler made one of these designs. The design used 10 engines of 1000 hp with pusher props. Span would be 94 m (308.4 ft). The design had 4 hulls and 2 stabilizers. Tails were connected to each other. Passengers were seated in the wing. The design of Dornier was easier to construct than this design.

 

Norman Bel Geddes (1893-1958), an American industrial designer, came in 1932 with a proposal for another giant. His Airliner # 4 was designed with assistance of the German engineer, Dr Otto Koller. Geddes design would be veeeery big. Span 160 m (525 ft), nine decks, two elevators, place for 451 passengers and a crew of 155. The hulls contained kitchens, crew quarters, lifeboats and … 2 aircraft's. These aircrafts could be launched in flight to the rear. If that would not be enough. There were also luxurious staterooms, a gymnasium, dining room with dance floor, promenade decks, verandas, bar and many more. To me this sounds more like a cruise ship than to an airplane. To get the plane in the air there were 20 engines. Typical for this design … there were also 6 reserve engines, which could be placed in flight. This power would get the plane to a cruise speed of 160 km/h (99 mph).

http://hotgates.stanford.edu/Bucky/dymaxion/belgeddes.htm Go check it out.

Several thought that this design could only be operational when using ground effect. I believe that his thought is right. Ground effect … to me is the way to create the giants of tomorrow.

At the beginning of WW II the Germans built another giant. It was a glider! The Messerschmidt 321 would be used during the invasion of England. The glider could carry a lightweight tank or many equipped soldiers. The Battle of Britain gave the Allied control over their own air. Using German gliders would be suicide under these conditions. So the plan for using the gliders dropped. But they equipped the glider with engines so they could use them as transport airplanes. First they used 4 engines, quickly they placed 2 more. The name changed to Messerschmidt 323. The nickname was "Gigant".

Control over the air was not the only problem of the Messerschmidt 321. Getting it into the air was another. There were no giant tow planes at that time. And the pilots were a bit skeptic about this plane made of wood, bars and fabric. They had to use 3 airplanes ("Troika-Schlepp") at once to tow the prototype into the air. The pilots of the test flights found out that the airplane was very stable in the air, but that you needed a lot of arm muscles to steer the plane. Soon they added place for a co-pilot. The problem with the tow plane dropped when Heinkel made their He 111 "Zwilling" ("Twin"). This was a combination of two He 111's with a extra engine in the middle. It became nearly a giant itself. This airplane had the necessary power for the Messerschmidt 321. Still they used rocket assistance to get the fully loaded gliders in the air.



The Messerschmidt 321 had several new features. It has a landing gear that it could drop. Well, it was not a landing gear, it was more sort of a take-off gear. The glider landed on skids. Also new was a loading door at the front. Using a ramp tanks, trucks, artillery or soldiers could easily enter the glider. When the glider landed, the tank drove through the front door. The Messerschmidt 323 gave the possibility to check the center of gravity while loading. Somehow they could see this at the landing gear (the "Gigant" had a new landing gear configuration of 10 landing wheels). But the most remarkable thing were the gunners who were placed in the wing. You can place pilots, gunners or other personnel anywhere you like in a giant.

As you can see, the Messeschmidt 323 is one of my favorites. I really love the simplicity of the design.

Messerschmidt 321
Span     55 m     180 ft 5 1/3 in
Length     28,15 m     92 ft 4 1/4 in
Height (on take-off dolly)     10,15 m     33 ft 3 1/2 in
Wing area     300 m2     3 229,17 sq ft
Maximum towing speed (He 111Z)     220,5 km/h     137 mph
Maximum towing speed (Troika-Schlepp)     212,5 km/h     132 mph
Minimum towing speed     159 km/h     99 mph
Normal gliding speed     140 km/h     87 mph
Glide ratio     1:8
Take-off distance (Troika-Schlepp and four 1102 lb rockets at normal loaded weight)     1204 m     3 950 ft
landing distance     400 m     1 310 ft


Messerschmidt 323 E-2 "Gigant"
Span     55 m     180 ft 5 1/3 in
Length     28,5 m     93 ft 6 in
Height     9,6 m     31 ft 6 in
Wing area     300 m2     3 229,17 sq ft
Weight (empty equipped)     29 208 kg     64 066 lb
Weight (maximum loaded)     45 230 kg     99 210 lb
Engines (Gnôme-Rhône 14N 48/49)     6 x 1140 hp
Speed (no load)     252 km/h     157 mph at sea level
Speed (maximum load)     238 km/h     148 mph at sea level
Economical cruising speed     225 km/h     140 mph at sea level
Range (normal tanks, maximum load)     1 100 km     684 mls at sea level
Climbing speed (maximum load)     264 m/min     866 ft/min

During WW II another giant was born on paper. Howard Hughes was a man who loved to create airplanes which reaches the limits. It had to be the fastest, the smallest or ... the largest. And this is the third reason to create a giant. The will to have the greatest (sounds like a typical male problem). Hughes design, named the "Hercules" (but better known under the name "The Spruce Goose"), was a answer to the need for transport in the Pacific. At that time transport by boat was dangerous. Many U-boats were waiting. So Howard Hughes wanted a large airplane to transport all what was needed by air. The design was on paper during the war, but the airplane flew after the war.

Hughes had many problems building the prototype. Mostly thanks to himself. He never could make up his mind. He changed the design several times. We will not bore you to death explaining all the other problems he had. But we can tell you ... the plane was huge.
It flew once. Not that it lacked the power, but Howard Hughes didn't get permission to take off. Hughes wouldn't be Hughes if he didn't show to the public that it could take off. So he got permission to make a taxi-run on water. During this taxi-run, he applied power, set the flaps on take-off and ... took off. Yes, it could fly. After this flight it was stored in a dome near the place where it flew. Recently they moved the whole airplane to Evergreen Aviation Educational Center in Mc Minnville in Oregon.

The Hughes HK-1 is still the largest airplane build.

Hughes HK-1 "Spruce Goose"
Wingspan     97,54 m     319.92 ft
Fuselage height     Approx. 9,14m     Approx. 30 ft
Cruising speed     Approx. 322 km/h     Approx. 200 mph
Maximum range     Approx. 4828 km     Approx. 3 000 miles
Endurance (cruise)     20,9 hrs.
Service ceiling     6 370 m     20 900 ft
Engines     8 Pratt and Whitney R-4360, 3 000 hp each
Propellers     8 four bladed Hamilton Standards, diameter 5,23 m (17' 2'').

 

 

There is another plane that is quite remarkable in design and size. What happened? Several airline companies dropped their Stratocruisers when turboprop and jet-engines became available in civil air transport. Stratocruisers could be bought at a cheap price. Most were bought by Lee Mansdorf and were stocked in California. Former bomber- and transport pilot John M. "Jack" Conroy lived there. NASA had in that time problems moving segments of the Saturn-rocket for the Apollo space project. Conroy left his job, took a loan and started work on a conversion of a Stratocruiser. He added 5 meter (16.40 ft) to the fuselage and placed a enormous "tube" in top of the lower deck.  Total internal stock volume became 826,5 m3 (29 187 cubic ft). The "Guppy" was born.



In 1960 he presented the concept to NASA-officers. NASA was pleased with the idea and asked for exclusive user-rights for two models. Airbus Industries was also interested and bought some models to transport Airbus-components to the final assembly. There were several sorts of Guppy's. The last version was the 201 with Allison turboprops.

I once saw a weird airplane over Aalst, Belgium at rather high altitude. It had a very fat fuselage. It could only have been a Guppy.

Conroy / Aero Spacelines Guppy 201
Span     47,62 m     156.2 ft
Length     43,84 m     143.8 ft
Wing area     182,52 m2     1965 sq.ft.
Cargo room diameter     7,5 m     24.6 ft
Cargo room length     34 m     111.5 ft
Weight (empty)     45 359 kg     100 000 lb
Weight (maximum take-off)     77 110 kg     170 000 lb
Maximum loading     24 494 kg     54 000 lb
Cruise (on 7620 m)     407 km/h     253 mph
Maximum cruise     463 km/h     288 mph
Climbing speed     457 m/min     1 500 ft/min
Ceiling     7 620 m     25 000 ft
Range (max cargo)     813 km     505 mi
Engines (Allison 501-D22 C turboprop)     4 x 3663 kW (4912 hp)

I know that the largest operational airplane is a design of the Russian firm Antanov. I will describe his forerunner, the Lockheed C-5 Galaxy. "Huh? Forerunner?" I hear you think. Let's say that the main difference between the Antanov and the earlier produced (first flight 30 June 1968) Galaxy is the tail. The stabilisator of the Galaxy is placed on top of the vertical tail. The Antanov has a conventional tail. The difference in size is a few meters (feet). I don't blame the Russians of making a copy, it is like the Russians said about their own design of the Space Shuttle "The laws of aerodynamics are the same to Americans or Russians".



The Galaxy was possible thanks to his engines. These new engines made it possible to design this airplane with just 4 engines. Using any other engine would lead to a lot more engines needed. It has the same basic shape as the smaller C-141Starlifter. A high wing with engines mounted in gondolas underneath, a T-tail and a raised back section with loading doors. But it has also a new design of nose. The nose can be raised to clear access to the cargo room. The Galaxy has the unique feature of "Roll in - Roll out". This means that a vehicle can ride onboard and ride off without turning or riding backwards.

The airplane has in a upper deck a roomy cockpit in the nose and a extra room for 73 passengers behind the main wing spar. The cargo room is 5,79 m (19 ft) wide and 36,88 m (121 ft) long and has a volume of 985 m2 (34786 cubic ft.). Height varies between 2,9 m (9.5 ft) (under the wing) to 4,11 m (13.5 ft) in the back section.

Lockheed C-5 Galaxy
Span     67,88 m
Length     75,54 m
Height     19,85 m
Wing area     575,98 m2
Weight (empty operated)     169 643 kg
Weight (maximum take-off)     379 657 kg
Maximum Speed     919 km/h
Maximum cruise speed     908 km/h
Climbing speed (at sea level)     525 m/min
Ceiling (at 278 960 kg)     10 895 m
Range (maximum)     10 411 km
Range (max. cargo)     5526 km
Engines (General Electric TF39-GE-1C turbofans     4 x 19 522 kg (191,27 kN)






I know that there are many other giants. But this collection has some unique features.


What will happen in the future? Will airplanes become bigger? Will a operational airplane be build that is even larger than the "Spruce Goose"?
I read that McDonnell-Douglas has a "Megaplane" on paper. It would be a two deck blended wing body (BWB) for 800 passengers. Range will be 7000 miles (11 250 km). Cruise speed 590 mph (900 km/h). Airbus Industries studies a "FW-900". It is a giant flying wing for 900 passengers. Range 7 457 miles (12 000 km). 4 turbofan engines would be mounted on pylons on the back of the wing-fuselage. Each would deliver 100 000 lbst (444 kN). Span 315 ft (96 m). And this span is very near the span of the Hughes HK-1.
Why such a large planes for passengers transport? Studies showed that bigger planes made the price for a flight cheaper. That is not hard to believe. I have one question. Where will they find airfields for these giants? Will there be flying boats again? Only the future will tell.