U.E.C.- Russian aircraft engines

The 24 ton engine would be for an An-124 replacement. A 50 ton engine could replace two 24 ton engines.
So you could make an An-124 class aircraft with twin engines.

The whole idea is to replace the An-124 with a new transporter project named Slon anyway.
But Slon is supposed to use four PD-35 engines and be larger than the An-124. At least that was the previous project.
50t power would be slightly higher than even the largest 777X engines.

The PD-24 engine proposal was supposedly a downscale of PD-35 using the same engine core so it should be fairly straightforward to do.
The concept is even if the engine core is heavier than it would be for an engine optimized for that thrust, you get decent performance by making weight savings elsewhere, like in the fan section with composite fan blades.
This engine would then supposedly be used either as an upgrade to old An-124 aircraft or new builds of this aircraft.

I also do not see how they can use the same components in PD-35 to make a 50t engine. Yet the article discusses this.
I think at best you would have to make an upscaled engine using similar technology to get to 50t but it wouldn't be the same engine.

I don't know how viable would such an hypothetical PD-50 engine be given Russia's limited aviation market. The 777X is basically posing itself as a twin jet 747 replacement. Given current COVID-19 travel restriction the aviation market is still severely constrained and the project is so delayed it might not ever be profitable and some models might get cancelled.

The CR929 is much smaller, on the weight category of something like the 787 or A330. This would be for a 777X competitor. Like the hypothetical Chinese C939.

Four engines would be safer. With regards to fuel consumption, this is more related to engine design, than number of engines. The BAe146 aircraft is a good example of this. It is a small quad engine aircraft with better fuel consumption that other twin jets of its time. The main advantage of the twin jet is you have lot less parts and maintenance per aircraft. So operating costs should be lower.

lancelot wrote:The PD-24 engine proposal was supposedly a downscale of PD-35 using the same engine core so it should be fairly straightforward to do.
The concept is even if the engine core is heavier than it would be for an engine optimized for that thrust, you get decent performance by making weight savings elsewhere, like in the fan section with composite fan blades.
This engine would then supposedly be used either as an upgrade to old An-124 aircraft or new builds of this aircraft.

I also do not see how they can use the same components in PD-35 to make a 50t engine. Yet the article discusses this.
I think at best you would have to make an upscaled engine using similar technology to get to 50t but it wouldn't be the same engine.

I don't know how viable would such an hypothetical PD-50 engine be given Russia's limited aviation market. The 777X is basically posing itself as a twin jet 747 replacement. Given current COVID-19 travel restriction the aviation market is still severely constrained and the project is so delayed it might not ever be profitable and some models might get cancelled.

The CR929 is much smaller, on the weight category of something like the 787 or A330. This would be for a 777X competitor. Like the hypothetical Chinese C939.

Four engines would be safer. With regards to fuel consumption, this is more related to engine design, than number of engines. The BAe146 aircraft is a good example of this. It is a small quad engine aircraft with better fuel consumption that other twin jets of its time. The main advantage of the twin jet is you have lot less parts and maintenance per aircraft. So operating costs should be lower.

Well, in addition to the an124 a 24 tons takeoff thrust engine could be used also on an aircraft like the proposed frigate ecojet (later proposal converted into 4 engines aircraft due to lack of modern engines with the desirede thrust)

Or even on a later larger version of the MC 21.

According to this (old) article,  also the mc21-500 and -600 are in considerations..


http://aviation21.ru/ms-21/

(...)
Perspectives

Within the framework of the Airplane 2020 program, the United Aircraft Corporation is considering the possibility of developing promising modifications of the MC-21 airliner for the period up to 2035. First of all, it is possible to modernize the MS-21 in terms of optimizing the specific fuel consumption and improving the aerodynamics of the liner.

Variants of a new narrow-body "single-aisle" aircraft MS-21-400, which will require engines with a thrust of up to 18 tons - PD-18, have been preliminary worked out. It is also possible to create aircraft of the family - MS-21-500, MS-21-600 with engines with a thrust of 20-25 tons and MS-21-700 with engines with a thrust of 30 tons.

A variant of the "universal" aircraft MC-21X, which can be positioned at a maximum flight range of 9,000-10,000 kilometers, is also being considered. In this version, the aircraft turns out to be more continental, but even taking into account the headwind, it can be operated on ocean routes.

They were talking about replacing the AN-124 with two aircraft... one slightly lighter and cheaper to operate with a 90 to 120 ton payload capacity which would be the Il-106, while a heavier aircraft able to carry a bigger payload than the An-124 and perhaps be adapted for external payload to be carried on its back with a 180 ton payload capacity called Slon.

With two 35 ton engines the Il-106 would benefit from lower drag with only two engines, simplified maintenance, and reduced fuel consumption, while having four 35 ton engines the Slon could manage up to 180 ton payloads quite easily as it would have similar engine power to the An-225 but less drag and much better fuel consumption and engine reliability.

For a 50 ton thrust engine two on the Il-96 would make it more efficent.

BTW where does all this crap about needing a completely new wing for an engine change?

And even if it is true, they have upgraded the wing on the Il-76 about four times already and on the Tu-95 twice too so it is hardly a big deal.

Getting a Russian engine is more important than worrying about having to redesign the aircraft... in this case two of the aircraft have not been designed completely yet so redesigning the wing.... they likely originally designed it for a specific power rating already so it wont need much alteration if any.

They would fit the PD-24 to existing AN-124s till they are worn out and they could use four PD-24s in an export oriented Il-106 with 96 tons of thrust it should be just fine with payloads up to 120 tons, but be smaller and lighter than the An-124 which should make it cheaper to operate with more fuel efficient and reliable engines.

Later on PD 35s could be fitted to the Il-106s with two PD-35s powering a lighter model able to carry 80 tons of payload with 70 tons of thrust as an export equivalent of the C-17... it would also give it engine commonality with the Slon with four PD-35s and 140 tons of thrust for a 180+ ton payload capacity transport.

If you try to equip an An-124 with two 50kgf engines you will need to design a new wing.

From what I can tell, the PD-35 is being driven because the PAK DA will likely use an engine in that power range, though it might be an internal engine more like a turbofan in a fighter aircraft than a high bypass airline engine type.

From that PD-35 they plan to make a two engine and a four engine version, where the two engine model is smaller and lighter and much cheaper than the An-124 to operate... an Il-106 class aircraft that essentially would be replacing the AN-22 which was a popular and useful aircraft, but with only two reliable and fuel efficient jet engines would also be much cheaper to operate than the bigger not so reliable and not so fuel efficient An-124.

The pay off would be that they would want Il-106 aircraft to replace both the AN-22 and An-124 aircraft but that creates the problem that the Il-106 that is smaller and lighter and more efficient might stretch to 120 ton payloads using inflight refuelling, but it wont carry the heavy payloads the 150 ton capacity An-124s could carry... which is why the Slon is being considered too... with four PD-35 engines it almost has as much thrust as the An-225 so a 180 ton payload should be easy and with the space industry expanding having an H tail aircraft able to carry outsized loads on it back would be useful too.

They wont need as many Slons as they have An-124s but they will need a lot more Il-106s than they had An-22s so they will end up using a lot of these engines.

The modular nature means scaling them up or down in thrust performance is supposed to be rather easy and straight forward so 24 ton thrust models for An-124s would mean being able to continue to use them much longer, improved performance and fuel economy and the ability to poach an export market and domestic civilian operators of the aircraft too.

It also creates a future potential for a twin engined Il-476 weight aircraft, while the twin engined Il-276 could have two PD-14 engines to replace the An-12.

There is little point in developing a new modular family of engines if you are not going to make them in different power ranges for different aircraft.

Obviously a 50 ton thrust engine would be for a large airliner or air transport plane or could be used for a powerful ship... military or civilian... or even a large hovercraft of maritime patrol aircraft... or power station...

You are changing the weight loading on the wing, how it's distributed, and how the air flows around it (remember the wing bends in flight). It's not going to work with the old. You might be able to get away with equipping the An-124 with four PD-24 engines and just need to update the flight control system. The design calcs would show for sure.

Designing planes and wings is what they do, there is no point in putting new improved engines on an existing aircraft and not doing anything to improve that aircraft.

The point is that the Il-106 was designed for specific engines but when those engines were cancelled they would hardly continue the project based on Ukrainian or foreign engines... they would have decided what engines they would use and plan for different wing and engine pod and engine pylon arrangements to suit each engine option... as I said they have been talking about the PD-35 for quite some time, and it is not an accident the PD-24 is similar in power to the engines it would be replacing on a Russian An-124.

The Slon was always expected to be a larger aircraft with better capacity than the An-124 based not only on their experience with that aircraft but also planning knowledge of new vehicles and equipment the Russian Army will want to be transporting around the place.

These plans of course can change... the withdrawal of the US from the INF treaty means much heavier truck vehicles with much heavier multistage IRBMs would become an option for air transport, but I suspect a 180 ton capacity Slon should be able to handle most options as it could probably carry ICBM level vehicles and missiles so IRBMs should be no problem either and scramjet powered hypersonic missiles will be much lighter and faster too.

Now it is true from a technical standpoint that Russia can redesign a wing for it. But that may not be the best option for resource (engineering and manufacturing) allocation

Pretty sure they could calculate which is the better options in terms of life cycle costs as to whether a much more powerful engine in a twin mount could work out cheaper than the current arrangement with PD-24s, but as far as I know the focus for PD-50s would be heavy airliners like the Il-96 or Il-86 with two engines to reduce maintenance costs and flight efficiency with lower drag.

For the PD-24 you can re-engine the An-124. But Russia can refurbish the D-18T and so that might not be the most cost effective approach. And there won't be aby more of the aircraft made. In order to make it cost effective, they need to produce the engine in volume. They could do this with a follow on design (you suggest an Il-106 but I am very skeptical that Ilyushin can pick up another design right now). But there is clearly nothing within the next five years.

The PD-24 would eliminate Ukrainian parts from the An-124 design for the Russians which would be useful and could be an option for a twin engined Il-476... two PD-24s would give 48 tons of thrust, while the PD-14s they are going to use for the upgraded Il-476 would give 56 tons thrust, the original Il-76 would have four 12 ton thrust engines which is also 48 tons thrust but with two engines better fuel efficiency and lower maintenance for a lower operational cost for lighter 40-50 ton payload operations it might be an option, and of course with four PD-14s on the Il-476 and two PD-14s for the Il-276s to replace the An-12s, perhaps two PD-18s for the Il-276 might give better range and payload performance options.

The PD-35 was for the PAK DA and Il-106 replacement of the An-22, using twin engine arrangements while four engine use on the Slon to replace the An-124... but who knows.

With PD-50 in the PAK DA for a bigger more capable aircraft and PD-24s to keep using the An-124s for much longer, and the Il-96 as a more efficient twin jet...

It all depends on the performance and capacity to produce engines and the efficiency of mass or small production batches.

For the PD-50, you can make a further stretch of the Il-96 - and build a whopping ten of them. Not cost effective at all. And there aren't any other possibilities in the near future.

But that is the question... with modular engine designs do you need to produce them in enormous numbers to make them cost effective or does their advanced design and low fuel burn and excellent reliability make them good cost effective engines anyway.

They may have projects we are not yet aware of, or they may simply see it as a future trend or market niche they see interesting to cover or where they want to compete with the West.

The 50 ton engine might be for a power station or ship... and the reliability and fuel efficiency and modular engine design might make it useful and viable low risk design.

You don't hear much about its big sister though - VK-1600. It was supposed to begin bench test trials late this year.

Wasn't that engine going to be used in the new Il-112 or Il-114 light aircraft?