Ask anything Thread


crash8pilot

Junior Member
Registered Member
The C-17, Il-76, and Y-20 are close equivalents. However, there are notable differences in landing gear design among them.
The C-17 landing gear configuration is 1 frontal (2 wheels), 4 rear (grouped in 3); 14 wheels total.
The Il-76 landing gear configuration is 1 frontal (4 wheels), 4 rear (grouped in 4); 20 wheels total.
The Y-20 landing gear configuration is 1 frontal (2 wheels), 6 rear, (grouped in 2); 14 wheels total.

What are the advantages and disadvantages of each arrangement and why does the Il-76 have so many wheels on its landing gears? Does this have to do with Russia's landing gear technology being behind that of US and China?
The heavier the aircraft, the more wheels it'll require to hold up the mass on the ground (and the impact force on landing). That said the empty weight and max takeoff weight of the the C-17 (~130tons empty, ~265tons max) is greater than the Il-76 (~100tons empty, ~200tons max), so I'd hypothesize that the C-17's wheels are probably made of material that allows it to supporting more mass per wheel than the Il-76, thereby also freeing up valuable space and weight for the plane to carry additional load.
 

stannislas

Junior Member
Registered Member
The C-17, Il-76, and Y-20 are close equivalents. However, there are notable differences in landing gear design among them.
The C-17 landing gear configuration is 1 frontal (2 wheels), 4 rear (grouped in 3); 14 wheels total.
The Il-76 landing gear configuration is 1 frontal (4 wheels), 4 rear (grouped in 4); 20 wheels total.
The Y-20 landing gear configuration is 1 frontal (2 wheels), 6 rear, (grouped in 2); 14 wheels total.

What are the advantages and disadvantages of each arrangement and why does the Il-76 have so many wheels on its landing gears? Does this have to do with Russia's landing gear technology being behind that of US and China?
Many Russian military aircrafts often have the requirement of landing on "muddy runways" or even flat grassland, whereas both the US and China don't put such hash loads on their planes and their landing gears/intake/etc..

So I won't say Russian landing gear technology is behind the US and China, but more like infrastructure in Russia is much lagging behind the US and China...
 

Julio Ramos

Junior Member
Registered Member
The C-17, Il-76, and Y-20 are close equivalents. However, there are notable differences in landing gear design among them.
The C-17 landing gear configuration is 1 frontal (2 wheels), 4 rear (grouped in 3); 14 wheels total.
The Il-76 landing gear configuration is 1 frontal (4 wheels), 4 rear (grouped in 4); 20 wheels total.
The Y-20 landing gear configuration is 1 frontal (2 wheels), 6 rear, (grouped in 2); 14 wheels total.

What are the advantages and disadvantages of each arrangement and why does the Il-76 have so many wheels on its landing gears? Does this have to do with Russia's landing gear technology being behind that of US and China?
Why would someone do that reading? The number of wheels is indicative of something? Fewer wheels means more technology?
 

Bright Sword

Junior Member
Registered Member
Has the PLAAF used JTO boosters to
shorten aircraft take offs with load ?
Am asking in the context of 4000m + altitude airfields in the WTC where altitude limitations are known to restrict weapons loads on combat aircraft.
The Soviet Union experimented with rocket boosters to keep combat jets flying in case of damaged runways.
The footage below of a Mig 19 making a rocket assisted take off is striking though it is reported that the G loads encountered on the pilot meant only pilots with exceptional physical strength could endure these takeoffs.

 

banjex

Junior Member
Registered Member
Then I beg your pardon in case I misunderstood your post.
Russian philosophy when it comes to military equipment (and in other areas) is to make things simpler and cheaper to enable mass production and redundancy. It's rooted in the way they won WW2.

On the high end, Russia can make some of the best equipment out there, but often in limited numbers. Russia's true strength is mass production (but at the expense of quality sometimes).

The larger number of wheels on the Candid can be interpreted in this light. There are more wheels because each individual wheel is a bit weaker (and cheaper to produce) than a Western chassis. But Russia uses more wheels to compensate. Also for redundancy in case of failures and the ability to land on rough air strips.

These small differences illustrate how China is trending away from its Soviet origins (mass) to a modern Western approach (quality and precision). Yes, Russia is trending this way too, but it seems like China may be further along in this process.

Indeed, ever since Deng, China's demonstrated a profound ability to adapt - in sharp contrast to the Soviets digging deeper in dogma. Hats off to the Chinese for what they've managed to accomplish - and all this fascinating analysis can be gleaned from something as miniscule as the number of chassis wheels on a cargo plane.
 

gelgoog

Senior Member
Registered Member
@halflife3 it is just that the Soviets typically had increased requirements for their aircraft to be able to land on rough or poorly paved runways than say the West back then or China today. With more road wheels you can distribute the weight better so you can land on rougher runways. This also applied to Soviet civil aircraft like the Tu-154.

Russia today is making huge investments into improving the quality of civilian runways and I would not be surprised if the same also applied to military airfields but Russia is quite large so they will likely retain a similar requirement.
 
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Tam

Colonel
Registered Member
Russian philosophy when it comes to military equipment (and in other areas) is to make things simpler and cheaper to enable mass production and redundancy. It's rooted in the way they won WW2.

On the high end, Russia can make some of the best equipment out there, but often in limited numbers. Russia's true strength is mass production (but at the expense of quality sometimes).

The larger number of wheels on the Candid can be interpreted in this light. There are more wheels because each individual wheel is a bit weaker (and cheaper to produce) than a Western chassis. But Russia uses more wheels to compensate. Also for redundancy in case of failures and the ability to land on rough air strips.

These small differences illustrate how China is trending away from its Soviet origins (mass) to a modern Western approach (quality and precision). Yes, Russia is trending this way too, but it seems like China may be further along in this process.

Indeed, ever since Deng, China's demonstrated a profound ability to adapt - in sharp contrast to the Soviets digging deeper in dogma. Hats off to the Chinese for what they've managed to accomplish - and all this fascinating analysis can be gleaned from something as miniscule as the number of chassis wheels on a cargo plane.
I am not sure that philosophy holds with the Russian even towards later in the Cold War. The problem with the Russians is they have a population problem; far too many died during World War 2 and that has a long last effect through the Cold War and the modern times in terms of demographics. Don't get the impression that Russia has a population greater than the US, it does not. Currently its population is only 144 million. That's less than half the US alone, and just slightly over that of Japan's. In terms of sheer potential manpower, NATO is all over the Russians.

This is one reason why Russian tanks are fitted with autoloaders to reduce the crew per tank, compared to NATO and US tanks that were manually reloading. Their move towards semi-robot Armata tanks even later also underlines this. And once again, recent efforts to develop robotic soldiers in the battlefield. Towards later, their Soviet Union, then Russia, the focus is to put as much bang into every available unit, new or old.

One of the reasons why the quality of the Soviet Union fell off --- earlier T-34s look better built than later T-34s, even if the later models had a more powerful gun --- is because Stalin sent experienced factory workers to the front lines where they ended up dying and leaving the country with less and less of a skilled workforce. The death of an entire generation of skilled factory workers would reverberate for decades to come as those skills were not replaced easily.

Fortunately for the Russians, those mistakes were countered by the fatal German obsession for over engineering. Whereas it might have been wiser if the Germans made their copy of the T-34, which there were prototypes, they went ahead to build complex, over engineered tanks that cost too much, needed too many man hours to build, ate too much fuel, and had reliability issues. Some of these ideas included electric drive on tanks --- Dr. Porsche championed that --- when the country is short for copper. Fast forward to today, there are still projects in the West that can be regarded as 'Elefants'.

What the Chinese defense complex is trying to do is taking these lessons, and their own experience, to avoid these two extremes, through a precise, well calculated and rational path of development.

As for the number of wheels on the Candid, they are expected to land on rough strips and damaged airfields, like what you would expect of a NATO airbase when the Spetnaz takes over.
 

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