PLAN Carrier Strike Group and Airwing

Re: J-15 Carrier Multirole Fighter thread

Paralay from keypublishing forum was so kind to do a translation of the few selected paragraphs of A. Fomin's book:

"Su-27K with incomplete filling of fuel tanks, depending on the amount of suspended missiles " air" , ranged from 25 to 28 tons while he was starting thrust 0.9-1.0 and could take off from the 1st or 2nd starting position on the deck of the ship ( the takeoff distance of 105 m ) . With full fuel tanks and maximum ammunition missiles " air" take-off weight increased to 32 tons, and thrust was reduced to 0.8. In this case vzleet aircraft had to be made with the third starting position ( takeoff distance of 195 m ) . Hence , the aircraft could start and the maximum load it with bombs and rockets .

Despite a significant increase in landing weight , compared with the Su -27 , the introduction of a new wing mechanization and canards possible to reduce the approach speed shipborne fighter up to 240 km / h (Su- 27, usually landing with a speed of 270 km / h and only it absorbs the leveling process to 225-240 km / h , depending on the weight of the seat ) . In this case the mean free path of the Su- 27K on the deck when braking its arresting gear was to be only 90 m"

So 28 tons from first position and 32 tons from second position. with, assumption on my part, some standard achievable wind over deck.

Another matter of discussion is empty weight. Fomin says su33 weighs 19600 kg while other sources (with no significant credibility though) say 18400 kg. Difference is, of course, rather big. 8,4 tons of pilot, equipment, fuel, weapons and pylons versus 9,6 tons for the assured launch from the forward launch positions. The former would allow for some 6,5-7 tons of fuel and enough armament. That in itself is still quite a bit, enough for 900-ish km combat radius high flying missions. If that's the worst case scenario like it seems it could be, that's still pretty good.

Re: J-15 Carrier Multirole Fighter thread

If J15 is to become a successful carrier based fighter it must fulfill all the roles of strike, escort, fleet air defence, force protection, close air support, deep support, reconnaissance and buddy refueling

J15 has a tall order lets hope with time they develop it into a fully fledge true carrier operator

Re: J-15 Carrier Multirole Fighter thread

Totoro said:

Paralay from keypublishing forum was so kind to do a translation of the few selected paragraphs of A. Fomin's book:

"Su-27K with incomplete filling of fuel tanks, depending on the amount of suspended missiles " air" , ranged from 25 to 28 tons while he was starting thrust 0.9-1.0 and could take off from the 1st or 2nd starting position on the deck of the ship ( the takeoff distance of 105 m ) . With full fuel tanks and maximum ammunition missiles " air" take-off weight increased to 32 tons, and thrust was reduced to 0.8. In this case vzleet aircraft had to be made with the third starting position ( takeoff distance of 195 m ) . Hence , the aircraft could start and the maximum load it with bombs and rockets .

Despite a significant increase in landing weight , compared with the Su -27 , the introduction of a new wing mechanization and canards possible to reduce the approach speed shipborne fighter up to 240 km / h (Su- 27, usually landing with a speed of 270 km / h and only it absorbs the leveling process to 225-240 km / h , depending on the weight of the seat ) . In this case the mean free path of the Su- 27K on the deck when braking its arresting gear was to be only 90 m"

So 28 tons from first position and 32 tons from second position. with, assumption on my part, some standard achievable wind over deck.

Another matter of discussion is empty weight. Fomin says su33 weighs 19600 kg while other sources (with no significant credibility though) say 18400 kg. Difference is, of course, rather big. 8,4 tons of pilot, equipment, fuel, weapons and pylons versus 9,6 tons for the assured launch from the forward launch positions. The former would allow for some 6,5-7 tons of fuel and enough armament. That in itself is still quite a bit, enough for 900-ish km combat radius high flying missions. If that's the worst case scenario like it seems it could be, that's still pretty good.

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Thanks for this, very enlightening.

I want to draw attention to the Take off weights from the two 105m positions and the 195m position.

From the 105m positions, with 0.9-1.0 thrust, they could take off with 28 tons.
From the 195m position, with 0.8 thrust, they could take off with 32 tons.

So the question is whether they have headwind?

I'm going to say no. I'm going to link back to the translated magazine scans again, and I'm going to quote the part which is relevant to these interesting stats you uncovered
http://www.sinodefenceforum.com/nav...-programme-news-views-44-6479.html#post247737

with 25 knots headwind Su-33 can take off from the 110m launch positions with 32 tons, MTOW, and with 0 headwind, launch is limited to 28.2 tons.
At the 195 launch position, Su-33 can take off with MTOW with 0 headwind.

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The numbers from the book correspond very well with the numbers from the magazine, better than if it was sheer coincidence. That makes me give credibility to the magazine scans, and also the numbers they provide (namely the various loadouts and range/endurance ratings).

Now, there are a few points to polish out:
The magazine says that at 0 headwind, the Su-33 can take off with MTOW (33 tons) from the 195m position, yet the book says it only achieved 32 tons. I suspect this is because thrust was at 0.8 rather than 0.9-1.0

There is also a "discrepancy" in the two sources: 110m vs 105m -- probably attributable to different measurement standards or such. I do not consider it a particular blight on the magazine's credibility.


So basically I have two conclusions:
Assuming Mr A. Fomin's book is fully credible (and there's no reason to doubt otherwise):
-Su-33 could take off with 28 tons and 32 tons from the forward and rear positions respectively, using 0.9-1.0 thrust levels and 0.8 thrust respectively. From comparison with the magazine, (and from the similarity in performance at 0 knots headwind), I believe it is more likely that the stats from the book are taken at zero headwind as well.
-I also conclude that this "proof" of the validity of the magazine's stats in that domain gives greater credence to its other numbers, namely the ones about endurance, range, payload.


The specific loadouts I'm talking about:

1: TOW 26 tons, fuel load 5.7 tons, weapons load, 4 R73 and 4 R77. Combat radii 660 km
2: TOW 27 tons, fuel load 6.3 tons, weapons load, 4 R73 and 2 R77 and 1 Kh-65E. Combat radii 710 km
3: TOW: 30.5 tons, fuel load 9.3 tons, weapons load, 4 R73 and 8 R77. Combat radii 1280 km
4: TOW 30.5 tons, fuel load 5.7 tons, weapons load, 22 x 250 kg bombs. Combat radii 700 km
5: TOW 31.9 tons, fuel load 9.3 tons, weapons load 4 R73 and 2 R77 and 4 Kh-31. Combat radius 1220 km.
6: TOW:31.4 tons, fuel load 9.3 tons, weapons load 4 R73 and 2 500kg class LGB and 1 1500kg class LGB. Combat radius 1250 km.

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Re: J-15 Carrier Multirole Fighter thread

Bltizo said:

The only place I see the 29940 kg figure is at the bottom, the "specs" list, and that is normal take off weight with full fuel, not maximum take off weight, which is listed as 33 tons.

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29940 kg = 20440kg (empty plane armed with 2xR-27 + 2xR-73) + 9500kg (full internal fuel tanks) . Theoretically , plane could takeoff in this configuration from 195m launch point , but I don't think Russians ever attempted that (could be wrong but there is no proof) . Btw , Su-33 with 4 AAMs would be standard scramble configuration .

33000kg = 19600kg (empty plane without missiles) + 9500kg (full internal fuel tanks) + 3900 kg (weapons) . Well , if you believe Su-33 could takeoff with that , then I have a bridge to sell you ...

Bltizo said:

Actually, Liaoning's longest take off point is 195m and Vikramditya's longest is 180m I believe.

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Yes , my bad , those are semi-official numbers (although probably without ramp ) . Nevertheless , 10km/h gain remains because of higher acceleration .

Bltizo said:

And what do you mean by "proportionally bigger"? Proportional to what? To length, to MTOW?
Furthermore, both Mig-29K and Su-33 use their body for lift as well, so simply looking at their wing area isn't wholly representative. Unfortunately it is difficult to eyeball overall lift.

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Mig-29K internal fuel is somewhere around 4450 kg (5670 l ) . Su-33 has 9500 kg (12100 l) .

Empty Mig-29K is 12700 kg , empty Su-33 is 19600 kg . Full fuel / empty weight : Mig-29K 0.35 , Su-33 0.48 . These are your proportions . I believe that Mig-29Ks engines are more efficient then Su-33s , therefore it needs less fuel - higher proportion of takeoff weight could be given to weapons .

As for lift , I would say on the first glance that Mig-29K body generates more lift (I could be wrong tho ) .

Re: J-15 Carrier Multirole Fighter thread

thunderchief said:

29940 kg = 20440kg (empty plane armed with 2xR-27 + 2xR-73) + 9500kg (full internal fuel tanks) . Theoretically , plane could takeoff in this configuration from 195m launch point , but I don't think Russians ever attempted that (could be wrong but there is no proof) . Btw , Su-33 with 4 AAMs would be standard scramble configuration .

33000kg = 19600kg (empty plane without missiles) + 9500kg (full internal fuel tanks) + 3900 kg (weapons) . Well , if you believe Su-33 could takeoff with that , then I have a bridge to sell you ...

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Clearly you haven't been following the previous few posts at all, where it has effectively been shown that the Su-33 could take off with such loads.
From A Fomin's book, Su-33 could take off with 28 tons from 105m, and 32 tons at 195m, likely under no headwind. From the magazine, it corrobates A Fomin's stats implying that performance is attained at 0 knots headwind, and also says that with 25 knots headwind the Su-33 could take off with MTOW (33 tons) from all the positions.

So yes, I do believe Su-33 can take off with 33 tons from a ski jump, so I'll take a look at that bridge, thank you very much.

Mig-29K internal fuel is somewhere around 4450 kg (5670 l ) . Su-33 has 9500 kg (12100 l) .

Empty Mig-29K is 12700 kg , empty Su-33 is 19600 kg . Full fuel / empty weight : Mig-29K 0.35 , Su-33 0.48 . These are your proportions . I believe that Mig-29Ks engines are more efficient then Su-33s , therefore it needs less fuel - higher proportion of takeoff weight could be given to weapons .

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What makes you think the Mig-29Ks engines are more efficient than Su-33s, and what makes you think that even if they are more efficient, that they would be more efficient to the point where it will effect the proportional load the Mig-29K can take off with at certain conditions.

And you still haven't clarified what you meant by Mig-29K having proportionally larger wings, which is what I was asking about.

As for lift , I would say on the first glance that Mig-29K body generates more lift (I could be wrong tho ) .

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So basically you have no idea and you're eyeballing just like the rest of us. I can say that I think the Su-33 generates more lift, that its engines are more efficient, so it can take off with more proportionally relative to the Mig-29K. But I would have no proof for that, the same way you don't have proof for your claims.


Look, clearly it is impossible any of us to argue whether Mig-29K or Su-33 is more weight efficient at take off. That is the entire point I'm getting at.
We don't have the resources or the specs at hand to calculate or derive such conclusions.
That is why the only logical and reasonable stance to hold the null hypothesis, which is that both would have similar maximum take off weights proportions dependent on the conditions that both are taking off in.

Re: J-15 Carrier Multirole Fighter thread

Issue I have with those scans is just what sort of magazine is that? are those their own calculations? or they got them from an official source? if so, which one?

While it can be just a simple mistake, notwithstanding to the numbers themselves, the inclusion of r77, kh65 and kh31 in the armaments list is highly suspicious. Contrary to some popular opinions online, there is no evidence su-33 was ever integrated with ANY guided weaponry save for r-73 and r-27. Also, looking at the timeline of its design and production, as well as the russian history through the 90s and 2000s where little to no investment was made anywhere, it's highly suspicious those weapons were indeed ever integrated on su-33.

while inclusion of headwind could indeed be one possible explanation - i offer another one: If the magazine numbers are by someone who knows his physics, while they may reflect true limits of the aircraft launches, they may not include safety margins. And those margins are something that operational su33 would always use in real world conditions. Loadouts and fuel quantities wouldn't be calculated on moment by moment basis, depending on where the wind blows, if it will turn away this minute or the next, will it add or substract from the ship's speed, whether the sea is relatively calm or it's causing ship to pitch and therefore possibly lower the objective angle of the ramp etc.

real world planning will always go on the safe side and use predetermined classes of fuel and armament loadouts. Even just a 10% safety margin (lets remember that usaf likes a 20 minute loiter time around base margin for their fuel allowance) would amount to 3 or so tons of difference.

On another note, we do know that taihang has some 5% more thrust than engines on su33 (and probably ones on j15). We also know there are bits of info about m1 variant of al31 being available or even ordered by chinese, and those are roughly the same thrust as taihang.

We suspect j11b is lighter than su27s, as per one jane's article. further differences in construction and newer, lighter electronics may possibly increase that still from the alleged 700 kg. coupled with stronger engine, some reengined j15 circa 2020 may quite plausibly be able to carry a whole ton of fuel/ordenance more.

Re: J-15 Carrier Multirole Fighter thread

Btw , one more thing about supposed 33 000 kg MTOW for Su-33 .

Max thrust from Su-33 engines is 2x 125.5kN = 251 kN . With mass of 33 000 kg , this would give acceleration of 7.61 m/s*s , disregarding friction and air resistance . If we take 195m takeoff length and round it to 200 m (to give us little bit more speed ) , exit speed would be something like 55.2 m/s = 199 km/h . Therefore , you would need very strong head wind to achieve minimal speed (in 240 - 250 km/h range , possibly more for fully loaded airplane)

If you repeat same calculation , but for 29940 kg , acceleration would be 8.38 m/s*s , exit speed would be 208 km/h , still a tight spot . And for 26000 kg (stated normal takeoff mass ) acceleration would be 9.65 m/s*s , exit speed 223 km/h . Calculate ship speed and headwind and you will get your answer about Su-33 capabilities

Re: J-15 Carrier Multirole Fighter thread

Totoro said:

Issue I have with those scans is just what sort of magazine is that? are those their own calculations? or they got them from an official source? if so, which one?

While it can be just a simple mistake, notwithstanding to the numbers themselves, the inclusion of r77, kh65 and kh31 in the armaments list is highly suspicious. Contrary to some popular opinions online, there is no evidence su-33 was ever integrated with ANY guided weaponry save for r-73 and r-27. Also, looking at the timeline of its design and production, as well as the russian history through the 90s and 2000s where little to no investment was made anywhere, it's highly suspicious those weapons were indeed ever integrated on su-33.

while inclusion of headwind could indeed be one possible explanation - i offer another one: If the magazine numbers are by someone who knows his physics, while they may reflect true limits of the aircraft launches, they may not include safety margins. And those margins are something that operational su33 would always use in real world conditions. Loadouts and fuel quantities wouldn't be calculated on moment by moment basis, depending on where the wind blows, if it will turn away this minute or the next, will it add or substract from the ship's speed, whether the sea is relatively calm or it's causing ship to pitch and therefore possibly lower the objective angle of the ramp etc.

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The rather specific nature of the stats (the full thing includes endurance for very specific missions such as CAP at various ranges, loiter, etc), makes me think they are not based on the author's own calculations.

I wonder if they might be sourced from original Russian stats (which is why the magazine uses Su-33 and russian munitions rather than J-15 and chinese munitions), possibly acquired from Ukraine with the original T-10K prototype SAC got their hands on? The real question is whether these stats are gained from tests or derived from stats.
The fact that Su-33 was never integrated with some of the weapons in question may be simply a matter of Su-33s being tested with dummies for those weapons, but they never got along to integrating them. Unfortunately that is an assumption on my part, and it is of course equally likely that the loadout stats are derived from known test results.

Unfortunately I'm not sure what the original magazine is. But it doesn't sound like the kind of stats someone outside of the industry can simply calculate, or indeed reveal, without some kind of consent.



As for safety margins, I make the assumption that safety margins are included, seeing as the previous stats are included with safety margins presumably intact as well. (And none of the loadouts exceed 33 tons, which is the claimed max safe take off weight from all three positions at 25 knots as well).


But what is your opinion on A Fomin's stats for 28 tons and 32 tons at 105m and 110m? Headwind or no headwind? My position is already pretty clear on this matter, and I use the magazine's similar conditions as a backup for my stance.

Re: J-15 Carrier Multirole Fighter thread

Bltizo said:

From A Fomin's book, Su-33 could take off with 28 tons from 105m, and 32 tons at 195m, likely under no headwind.

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I dispute that with my own calculation above

Bltizo said:

What makes you think the Mig-29Ks engines are more efficient than Su-33s

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They are new design , with some improvements in technology . Compare ranges of Mig-29K and Su-33 .

Bltizo said:

And you still haven't clarified what you meant by Mig-29K having proportionally larger wings, which is what I was asking about.

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Wing loading . Mig-29K has lower wing loading .

Re: J-15 Carrier Multirole Fighter thread

thunderchief said:

Btw , one more thing about supposed 33 000 kg MTOW for Su-33 .

Max thrust from Su-33 engines is 2x 125.5kN = 251 kN . With mass of 33 000 kg , this would give acceleration of 7.61 m/s*s , disregarding friction and air resistance . If we take 195m takeoff length and round it to 200 m (to give us little bit more speed ) , exit speed would be something like 55.2 m/s = 199 km/h . Therefore , you would need very strong head wind to achieve minimal speed (in 240 - 250 km/h range , possibly more for fully loaded airplane)

If you repeat same calculation , but for 29940 kg , acceleration would be 8.38 m/s*s , exit speed would be 208 km/h , still a tight spot . And for 26000 kg (stated normal takeoff mass ) acceleration would be 9.65 m/s*s , exit speed 223 km/h . Calculate ship speed and headwind and you will get your answer about Su-33 capabilities

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Do your calculations include the effect of the ski jump?

Add in the ski jump, combined with 25 knots of headwind (46.3km/h), and things start looking convincing.

And of course speed the only factor in a takeoff -- lift/angle of pitch is just as important. That's the entire point of the ski jump, to enhance the latter.