PLAN Carrier Construction

chuck731 said:

I think there are other reasons to think the current geometry of J-15's nose gear isn't ideal for a minimum change adaptation to cat launch.

Take for example the point where the back strut connects to the nose gear. The strut on the J-15 connects to the nose gear relatively high up on the gear leg compared on the what is found on the known catapult adapted gears such as those on the F/A-18, F-14, A-6, F-35C, and E-2. Having the strut connection high up means the point of connection of catapult tow bar would also be high up. This would force J-15's tow bar to be very long in order to reach down to the deck and engage catapult shoe. I wouldn't say it is impossible to adapt this configuration for cat use, but it would seem much less than ideal.


The same with the long oleo in the nose gear. J-15 gear back struct connects at the same level as the strut on the Su-27/J-11. In Su-27 this facilitates a long oleo strut in the nose gear, which improves available suspension travel when the nose gear is rolling over rough ground, and this imporves Su-27's ability to taxi, land and take off on poorly prepared fields. It appears to me J-15 has the same oleo length as Su-27/J-11. But on a carrier the field is as good as it gets. Having a long oleo could actually be a problem because when the catapult fire, it would cause the long-travel oleo to compress a lot, which would cause the aircraft to pitch down a lot as it begins its roll. Again, I can't say this makes catapult adaptation impossible, but it certainly doesn't seem the J-15 gear has been optimized for this possibility.

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latenlazy said:

All this talk about how the J-15 isn't optimized for CATOBAR brings up an interesting idea. What if the J-15 is only intended to operate off Chinese STOBARs, will never be optimized for cats, and only enters limited production. Instead, CATOBAR optimization will be reserved for a next generation naval fighter, to be timed for production with the completion of the first CATOBAR carrier.

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kwaigonegin said:

or one could also ask what were the former Soviet Navy intending to fly off of the Ulyanovsk? she had waist cats. She was probably only a couple years away from completion but I don't think Russia had any catapult capable fighters at that time.

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kwaigonegin said:

or one could also ask what were the former Soviet Navy intending to fly off of the Ulyanovsk? she had waist cats. She was probably only a couple years away from completion but I don't think Russia had any catapult capable fighters at that time.

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chuck731 said:

She was probably at least a couple of years away from launching, maybe 5 years from sea trial, and 7 -10 years from first deployment.
Known aircraft types meant for her, such as yak-44 AWAC, haven't even reached prototype stage yet when her construction came to a stop.

The fact that she had nose ramp suggests su-33 weren't going to use catapults. Her waist catapults were probably for her Yak-44 AWACS, which were far heavier than the E-2, and any prospective new heavy strike aircraft she might carry to give her real strike capability. I wonder if some more serious modification of the su-27, along the lines of su-34, were envisioned for her.

Of the entire su-27 family, only the su-34 has a totally different nose gear arrangement from all the other members.

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chuck731 said:

What motivated the ramp on the ulyanovsk is probably not quite "if it ain't broke, don't fix it". When Ulysnovsk was being designed the the kuznetsov and its matching STOBAR aircraft hasn't actually gone to sea yet, and the concept of ramp launched conventional aircraft in a STOBAR arrangment hadn't been proven to not be broken from the get go yet, anywhere.

CATOBAR, on the other hand, has been proven daily for 40 years.

What is clear is when the pure STOBAE Kuznetsov was approved first, there were no CATOBAR carriers in soviet future plans yet. The slightly later CATOBAR ulyanovsk actually represented a significant departure from original plans that occurred after kuznetsov was approved. So it might have simply been ploy to make the change of plan more economical and therefore easier to swallow to give CATOBSR Ulysnovsk the ability to use aircraft already designed for, but not yet proven with, the STOBAR kuznetsov.

It may also reflect lack of confidence that catapults would work with satisfactory reliability when the ship went to sea.

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latenlazy said:

I seem to remember that one of the reasons they initially went with a STOBAR was that the arctic waters it was expected to perform most of its operations were particularly rough, and CATOBAR would have been the riskier option due to this.

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latenlazy said:

I seem to remember that one of the reasons they initially went with a STOBAR was that the arctic waters it was expected to perform most of its operations were particularly rough, and CATOBAR would have been the riskier option due to this.

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